Published 2025-12-23

Digital sensors are becoming increasingly common in metrology. But what exactly is a digital sensor, how does it work and what are its practical benefits? Here we cover the basics.

What is a digital sensor?

A digital sensor is a sensor that measures, for example, temperature or humidity and sends the measured values as digital information to an instrument or a data logger. The sensor processes the measurement data itself and sends ready-to-use values, providing fast and reliable readings in the instrument. Analog sensors instead send a continuous current or voltage signal that the instrument must interpret.

Why do digital sensors provide better accuracy?

What makes digital sensors particularly accurate is that both the measurement and the interpretation take place in the sensor. With analog sensors, accuracy is determined by both the instrument and the sensor, and measurement data can be affected by electrical noise or voltage drops on the way to the instrument before the signal is interpreted. Because digital sensors send ready-to-use values, measurements remain stable all the way from sensor to instrument.

Digital technology also allows for higher resolution, often with more decimal places. The result is more reliable and comparable measurements, reducing the need to re-measure.

What are the main benefits of digital sensors?

• Easy integration and more stable measurement
  The instrument automatically recognizes the sensor type and receives ready-to-use measurement values directly. This provides higher accuracy and reduces the risk of both misalignment and incorrect readings.
  
  
• Flexibility
  Digital transducers can be seamlessly integrated into instruments and measurement systems that support different transducer types or multiple measurement channels. Most of Testo’s digital transducers use the same type of connector, making it easy to connect and switch between different transducer types in the same instrument.
  
  
• Easy identification
  Digital sensors have unique serial numbers, which simplifies tracking and management of the measuring equipment. Each transducer is calibrated as a separate unit and has its own calibration document (easily accessed by scanning a QR code on the transducer once it has been calibrated with us).
  
  
• Calibrate without pausing measurements
  Since digital sensors are calibrated separately, you can send the sensor for calibration without having to send the entire instrument. Therefore, by replacing the sensor, you can continue your measurements even when a sensor needs calibration.
  
  
  

Measuring instruments for digital sensors

Published 2026-01-29

The airtightness of a building affects everything from indoor environment and ventilation to moisture safety and energy use. Yet the importance of airtightness is often underestimated in house construction and renovation. To check airtightness, new buildings are usually tested with a Blower Door – a method that provides a reliable measure of the building’s total air leakage.

– “Airtightness is essential for a building to function as intended,” says Lars Tobin. He has worked with testing since the 1990s, including at SP (now RISE), and teaches airtightness and leak detection. In an interview with us, Lars explains how small leaks can have major consequences and why systematic measurements are crucial for a sustainable construction project.

Why is airtightness so important?

– A leaky house is not comfortable to live in. It often leads to draughts that reduce comfort and make it harder to keep energy use down. Comfort and energy go hand in hand. If you don’t have comfort, you don’t have good energy management,” says Lars.

But there is more to it than just energy optimization. Airtightness also affects moisture safety, fire safety and the quality of the indoor environment.

– Many people forget that it’s about fire safety, for example how easily a fire can spread between apartments. And about creating a clean indoor environment – you don’t want radon or other unwanted emissions getting in, or cigarette smoke from the neighbor. Airtightness is about human health and safety,” he explains.

A tight air barrier is essential to stop moist air from leaking into the structure and prevent condensation in cold parts of the house, which otherwise risks leading to moisture damage. During his many years in the construction industry, Lars has come across countless leaky buildings that suffered from moisture damage.

– Much of the moisture damage we see today could be prevented with the right knowledge and tools. Ensuring good airtightness avoids problems both during the construction process and in the long term. At the same time, airtightness affects how well the ventilation system works. In an airtight building, a larger proportion of the air enters through leaks instead of through the vents, making the ventilation flow difficult to control, especially in F-systems and to some extent in FT-systems.

When should the blower door test be conducted?

Air leakage is not always visible to the naked eye and without the right measurement method, critical leaks can easily be missed. For new construction or major renovations, the building is therefore tested with a Blower Door.

– It’s important to test the house at an early stage so that any shortcomings can be rectified. If you only discover problems after the internal walls are in place and everything has been plastered, it can be an expensive story to correct,” says Lars.

If deficiencies are found, it is always advisable to follow up with a new test after the measures to ensure that the desired result has been achieved. A Blower Door measurement shows the overall airtightness of the building, but to find exactly where the air is leaking, the test needs to be supplemented with leak detection. This can be done with a thermal imaging camera or smoke, depending on the season and prevailing conditions. A thermal imaging camera is useful when there are temperature differences between the indoor and outdoor environment. Smoke works all year round, but is a more time-consuming method.

How to get reliable results

– Many people think that experience is enough to know when a house is airtight enough. But airtightness must be checked, no matter how confident you are in your own ability, says Lars. He recommends the following structured approach:

1. Check drawings in advance – can you build airtight from the plans?
2. Educate staff on site – awareness of all construction workers is crucial.
3. Control during the construction process – have someone other than the builder carry out visual checks.
4. Early-stage pressure testing – address any issues and retest to verify the results.

While conducting a blower door test is relatively easy, attention to detail is what ensures reliable results.

– Sealing all leaks that are not included in the pressure test is essential. It is important to pay attention to all the details: are the windows closed? Is it tight around the penetrations? Is there water in the floor drains? And if it’s too windy outside, the curves can be uneven and the measurement results uncertain. It requires accuracy and some experience not to miss anything,” says Lars.

During our one-day course in airtightness testing, Lars goes through practical testing with Blower Door, common sources of error and what is required to get reliable results. The course is included when you buy a Blower Door from us.

Airtightness testing as quality assurance

There are no rules on how airtight a building must be – only that it should be “as airtight as possible”. Lars therefore emphasizes that developers should set clear requirements for airtightness already at the planning stage, so that there are concrete benchmarks to follow throughout the construction process.

For him, airtightness testing provides more than a measurement. It is a tool to control the quality of the work and an integral part of the quality assurance of the construction project.

– Pressure tests serve as a verification of work quality. They help contractors to see if the building is of high standard, while ensuring it is safe to occupy and sustainable in the long term. The energy savings provided by an airtight building are just a bonus – the most important thing is people’s health and safety.

He concludes with advice for construction consultants and contractors:

– Consider airtightness as part of a systems approach. Set a clear requirement for airtightness, verify it with testing and leak detection, and see the connection between construction, ventilation and airtightness. This will result in a safe and sustainable building.

Get started with airtightness testing

Published 2025-10-15

When the cold weather comes, buildings are put to the test. Uneven heating in apartments, cold radiators and draughts from leaky windows are common problems that both affect comfort and drive up energy costs. With the right temperature measurement in your buildings, you can quickly pinpoint causes and take action – for efficient energy optimization and a comfortable indoor climate all year round.

IR thermometers and thermal imaging cameras are reliable tools for operations and building technicians who want to optimize heating, reduce energy losses and prevent indoor temperature complaints from tenants.

Accurate temperature measurement – the basis for effective troubleshooting

Identifying the causes of temperature problems in a building and taking appropriate action requires accurate measurements in several locations. The air temperature should be measured within the occupied zone – the area where people normally stay. This zone is defined by two horizontal planes, 0.1 meters and 2.0 meters above the floor, and by vertical planes located 0.6 meters inside the external walls. In front of windows and external doors, the distance is 1.0 meter.

Read more about measuring points in the occupied zone

Domestic water should also be checked to ensure that both cold and hot water are at the correct temperature according to current legal requirements. Water temperatures that are too low can pose health risks, such as the growth of legionella bacteria. According to the Public Health Agency of Sweden, the temperature of domestic hot water should not fall below 50°C in the pipes.

Accurate temperature measurements and documented anomalies not only provide answers when troubleshooting or when tenants experience problems with the indoor climate – they are also an effective tool for identifying opportunities for energy optimization and cost savings in the building.

Fast and reliable temperature measurements with IR thermometer

With an IR thermometer, you can quickly and easily measure the temperature of surfaces such as radiators, floors, walls and windows using infrared radiation. Testo’s IR thermometers have an adjustable emission factor, allowing you to customize the instrument for different materials and get more accurate measurement results. Connect a sensor to also measure temperature in air and water. The wide range of applications makes the Testos IR thermometers a very useful instrument that fits in every building technician’s toolbox.

Read more about IR measurement and the emission factor

Detect heat leaks with a thermal imaging camera

A thermal imaging camera is an invaluable tool for both energy optimization and troubleshooting in offices, business premises and apartments with uneven or low heat. With detailed thermal images, you can quickly detect thermal bridges and leaks in the building envelope, for example around windows and doors where cold air can leak in.

Energy losses caused by leaks in the building envelope are often easy to fix, but can be very costly if ignored, especially during the coldest months. By documenting heat leaks and anomalies, you will have a clear basis for planning energy measures. Identify problem areas early and plan interventions such as window replacement or additional insulation to reduce energy costs and avoid tenant complaints. With Testo thermal imaging cameras, you can easily save thermal images and analyze the results in the associated IRSoft software – for even smoother energy optimization.

Education and training

When you buy a thermal imaging camera from Nordtec, our basic thermography course is included(not applicable to testo 860i), so you can get the most out of your instrument. Learn to understand the functions of the thermal imaging camera, interpret thermal images and act on the results.

Read more about thermal imaging cameras

The right instrument for the right purpose

Published 2024-11-22

Setting up ventilation is important to ensure a good indoor climate and to keep operating costs down. But, as many of us know, it is often a time-consuming process, especially when it comes to large systems where several technicians often have to work together to measure flow and pressure several times in different places in the buildings to achieve optimal ventilation adjustment.

Thanks to the Celsicom V600, these problems are a thing of the past. In fact, with the help of the meter, a ventilation technician can perform really big adjustment jobs all by himself.

Adjustment of ventilation with Celsicom V600

All you need to set airflows in a system is our new tuning instrument, an optional airflow meter and a mobile phone or tablet. Here is our step-by-step guide to setting up ventilation with the Celsicom V600:

• Remove the sliding cover of the Celsicom V600 and scan the QR code inside with a mobile/tablet
• Create an account on the Celsiview cloud service webpage that appears on the screen
• Add the Celsicom V600 and choose the instrument for your measurement
• Identify the weakest point of the ventilation system, i.e. your reference device
• Enter the K-factor and projected value for reference actuators and other actuators
• Connect the calibration instrument to the reference device and the measurement is underway.
• Celsicom V600 guides you through the entire proportional adjustment process
• The mobile/tablet displays the current adjustment values for each sensor
• If a pressure change occurs in the system, new values are calculated – in seconds!
• Finally, raise or lower the reference actuator to 100% (as designed) and the values of the other actuators will be automatically adjusted

“No need to go back and check measurements”

This is how ventilation adjustment works with Celsicom V600. One person who has discovered the advantages of the new adjustment instrument is ventilation technician Tor Halvorsen at VXPro AB. Tor has used the instrument for several large adjustment jobs and believes that it facilitates and improves his job in several respects.

– I don’t have to spend time doing my own calculations, nor do I have to go back and check the reference device. In the past, it often took at least three trips to get all the values right. Now I get it right straight away,” says Tor, adding that the Celsicom instrument makes him more efficient.

– It saves at least a third of the time. Up to half in some cases. Depending on the accessibility and complexity of the systems.

Impressively accurate alignment

In addition to the time savings, the Celsicom V600 and Celsiview allow Tor to perform large adjustments with impressive precision. He often exceeds the requirement of six percent accuracy in the adjustment between the sensors by far.

– “I often get down to three percent accuracy, which benefits everyone. The tenants get a comfortable indoor climate and the property owners lower energy consumption,” says Tor Halvorsen, who sees how the smart measuring instrument allows him to “do more in less time”.

– This is a great solution that gives me more capacity every day of the week!

Discover other Celsicom meter boxes

The Celsicom product family also offers measurement boxes for accurate measurement and analysis of other quantities such as temperature, humidity and differential pressure to ensure safe and optimal environments in many different industries.

Companies operating in sectors such as construction, real estate, moisture damage management and the food industry benefit greatly from Celsicom’s flexible and precise measurement boxes. Whether you need to ensure indoor air quality, monitor workplace conditions or meet critical environmental parameters, Celsicom can help you do so with the highest accuracy and reliability.

Curious about the user-friendly, reliable and versatile Celsicom? Read more here!

Published 2025-09-22

Ventilation technician Tor Halvorsen uses Celsicom V600 reference sound level meters for ventilation adjustment.

Med över 20 års erfarenhet i branschen vet ventilationstekniker Tor Halvorsen vikten av pålitlig mätutrustning för effektiva injusteringar. Sedan drygt ett år använder han Celsicom V600. Resultaten har varit otvetydiga: mindre tidsåtgång och precisare luftflöden, jämnare drifter och betydande energibesparingar.

Tor Halvorsen and his colleague Patrik Pålsson at VXPro AB specialize in ventilation adjustments in all types of properties. Everything from homes belonging to small and large housing associations to commercial premises and offices in properties of all sizes.
– When we work for housing associations, it can be from twenty to several hundred apartments with three to seven measuring points per apartment. For example, in a residential area with 300 apartments, there may be an average of around 1,500 air diffusers. In addition, there are public spaces such as laundry rooms and community halls. So it’s important to work smart with ventilation adjustment,” says Tor Halvorsen.

Traditional tuning – time consuming and outdated values

Traditional tuning means that the reference sensor is measured repeatedly during the tuning of the other sensors. This is necessary to see the current ratio (the relationship between the current value and the target value) to adjust against. The ventilation technician then has to go back to the reference device often, usually three times – sometimes up to six or seven times, to check it. After a while, it becomes uneconomical to go back to the reference device after each throttling. If control measurements are not taken, the result is that the current quota is not always available.
The solution to avoid time-consuming control measurements and minimize adjustment errors is real-time reading of the current ratio. With traditional tuning, real-time reading can only be achieved by a technician continuously measuring the reference actuator and communicating the new ratio via radio or telephone to the colleague throttling the actuators.

Celsiview cloud service – real-time reading with Celsicom V600 for fast and more precise ventilation adjustment.

Averaging is the key

Many measurement solutions for real-time readings consist of reference dosimeters connected via radio or Bluetooth (with limited range) and a base station and modem. The Celsicom V600 consists of a single unit: a compact, battery-powered reference densitometer.
After the meter automatically connects to the mobile network, the ventilation technician continues his work in the web-based Celsiview cloud service on a mobile or tablet. The screen displays the current values of the reference actuator and guides the technician through the adjustment of all actuators.
– Thanks to the Celsicom V600 averaging, I can see immediately if the values are within the right range. I can easily see fluctuations in pressure and use the average instead. This means I can often get the difference down to two or three percent, which is more accurate than the normal method error of six percent,” says Tor.

“Small and flexible measurement solution”

Tor previously used Celsivent, the predecessor of the Celsicom V600. He was quickly impressed by the new model:
– The V600 is a small and handy measurement solution. Apart from the meter itself, all you need are batteries and measuring hoses, an optional airflow or pressure gauge, and your regular mobile phone or tablet. It starts up and connects quickly. After a few minutes, you are ready to start measuring.

Tor also appreciates a number of small but important details that make his job easier. These include the magnetic bracket and the measuring hook that allow Tor to easily and safely connect the V600 to supply air and exhaust air devices.
– I also like the fact that the battery status is clearly displayed on the tablet, so I don’t have any unpleasant surprises. The operating time is also really good. I can often measure for several days without having to change the batteries in the V600, which is powered by standard AA lithium batteries.

Emergency jobs cleared quickly

Tor and his colleague Patrik recently got a clear proof of the benefits of Celsicom V600 during a job on the island of Öckerö outside Gothenburg. At short notice, they responded urgently and made adjustments in two properties with a total of 18 apartments.
– We expected to spend eight hours, but finished in five. And that’s despite the fact that the installation wasn’t finished when we arrived. We even had to help the electricians with the control technology to get the fans going,” says Tor and adds:
– “It was good for us to once again get confirmation of how well the Celsicom meter works. The adjustment itself took about three to four hours, which is also three times faster than traditional ventilation adjustment!
No wonder that Celsicom V600 has become an obvious work tool for Halvorsen and Pålsson at VXPro AB.
– Everyone I have recommended it to is happy. It is an invaluable tool for anyone working with ventilation adjustments.

Published 2023-11-16

The thermal imaging camera is a versatile working tool to say the least. With its detailed thermal images, you can ensure optimal indoor climates for people, equipment and machinery. And, more importantly, you have an opportunity to detect and fix costly energy wasters. Still high electricity prices make this undeniably interesting, right?

The colder the weather, the clearer the thermal images.

It is worth taking thermographic measurements of facades and indoor environments at regular intervals. However, in spring and summer it can be difficult to detect cold drafts or heat leaks. The reason is that the outdoor and indoor temperatures are too close together, which means that any problem areas are not as visible on the camera screen.

In other words, thermography is most effective with larger temperature differences outside and inside the objects being measured. When there is a difference of around 10 degrees between indoor and outdoor temperatures, powerful ‘flower patterns’ often appear on thermal images. They indicate leaks in the house shell where there is a risk of cold air entering or hot air escaping.

Practical conditions

In addition to a temperature difference of 10°C between outside and inside, these conditions should be met in order to obtain reliable thermal images:

• There should be stable temperature conditions
• Sun or other point sources of heat shall not illuminate the measuring surface.
• The surface to be measured must not be rain-soaked or damp.
• Make sure you have enough time to take and analyze pictures in peace and quiet.

Common problematic surfaces

The high electricity prices of recent years make thermography extremely valuable. IR measurement and detailed thermal images are an effective weapon in the fight against energy costs. A thermal imaging camera from Testo is a relatively small investment that quickly pays for itself.

At the touch of a button you are up and running and measuring. Either from outside or inside the property. You will usually find thermal bridges in ceilings and walls, balconies and attics, and heavy intermediate floors. It may also be worth focusing on surfaces around doors and windows. Often cold spots and heat leakage are due to defective, carelessly installed or non-existent insulation.

After taking a thermal image, you can analyze it either on the camera’s screen or on your computer, and then present the results to the person making the decision on what to do about the energy loss.

Published 2023-10-19

It is important to inspect certain critical environments at regular intervals in order to detect and remedy any mold problems in good time. In crawl spaces and attics, it is common for moisture to cause microbial growth. Here, experienced moisture consultant Kim Olmås explains how mold develops, how to detect it and what measures you should take.

Crawl spaces and attics should be inspected at least once a year. The best way to detect moisture is to measure. These measurements should be taken at times when the risk of high moisture levels is greatest. Grounds are usually wettest in late spring, summer and fall. In attics, moisture is usually highest in late fall, winter and early spring. If you want to keep an eye on moisture all year round, it is best to get one or more connected measuring boxes from the Celsicom remote monitoring system.

We caught up with Kim Olmås, a certified moisture expert and construction doctor with extensive experience in the industry, to sort out some basic questions about moisture and mold.

How does moisture occur in crawl spaces and attics?

– In crawl spaces, it’s about warm, moist outdoor air finding its way in and meeting a colder foundation. This raises the relative humidity (RH) and can cause microbial damage to organic matter and emissions from chemical decomposition processes. The soil surface also gives off moisture, just as rain and groundwater can do,” says Kim Olmås and continues:

– In attics, it is mainly warm, humid air from inside the house that comes up through leaks in attic floors, penetrations and attic hatches. The warm, moist air raises the RH value in the cooler attic space or condenses against a cold roof, which also raises the humidity.

External leakage can also cause elevated RH values and microbial damage such as mold, bacteria and rot as well as emissions from chemical decomposition processes. High moisture levels are often due to the inability of the house’s ventilation system to remove the moisture generated by washing, showering, cooking, sweating and exhaled air. Outside air and water leaking into the attic also contribute to moisture.

On which surfaces does mould occur?

In crawl spaces, it is common to see growth on the blind floor (underside of the floor joists) in the form of white, gray or black patches, or on the ground surface. In attics, mould can grow on the inside of raw board, roof trusses, floorboards and loose items such as fabric and cardboard boxes.

– But not all the growth is visible and it can be very moldy without you noticing,” says Kim Olmås.

– Also use your nose to identify, as far as possible, unusual, pungent smells that may reveal microbial growth in the space in question. However, the best way to really know is to do a moisture measurement yourself or with the help of a moisture consultant or submit material samples for analysis by companies such as Botaniska Analysgruppen and Pegasuslab.

What can be damaged by damp and mould?

– Crawl spaces initially produce mold, bacteria or blue stain fungi that grow on the surface and give off odors, emissions and endotoxins (harmful bacteria). However, if it is really damp, i.e. if the moisture content of the wood is up to 26-30%, rot fungi appear which break down the wood and reduce its strength. There may also be mold on the ground.

The same development of mold growth is common in attics. There is also a risk of damage to furniture (organic material) and insulation from microbial growth.

What are the critical levels and how to act?

– In crawl spaces, the critical RH value is 75%, which corresponds to about 17% moisture content in wood. At the same time, we know that already moisture-damaged or contaminated surfaces can develop microbial growth much earlier,” says Kim Olmås:

– To combat mold, a crawl space dehumidifier is usually installed and set to a maximum of 60 percent relative humidity, which is the limit for rust on metal. Dehumidifiers are the most effective measure, but they require some action and supervision.

When installing a dehumidifier, you will need to seal all outdoor air vents in the foundation (to prevent outdoor air from leaking in), clear the soil of organic material and apply a vapor barrier to the soil surface. The dehumidifier may require filter replacement and other services after a certain period of time.

In principle, the same moisture values apply to attics. However, dehumidifiers are not often installed in attics. Instead, the focus is usually on reviewing the ventilation of the house and ensuring that the moisture produced indoors is transported out of the house via the ventilation system.

– It may also be necessary to seal the top of the attic so that warm, humid air cannot penetrate so easily. In addition, it may be a good idea to review how the attic is ventilated. Too much attic ventilation tends to increase the moisture level and thus also increases the risk of moisture-related damage.

Kim Olmås is pleased to note that more and more property owners and operators have begun to check moisture and mold more frequently.

– The most critical aspect of moisture damage is that it can affect the indoor environment and make people living there sick. Often caused by mold and emissions from both microbial growth and chemical degradation processes.

Measurement solutions for crawl spaces and attics

Published 2023-10-05

ECiS – Energy Concept in Sweden AB is a company that offers solutions to save energy, reduce environmental impact and improve the indoor environment both in buildings and/or processes. Anders Tennerhed from ECiS works with indoor climate analyses and also collaborates with Nordtec as a course leader for our indoor climate courses. We met Anders and asked him a few questions about indoor climate analysis and ECiS.

Who are your clients and why do they need your help?

– For our part, we can say that there are two directions. On the housing side, there is often a need to investigate cold apartments. It must not be due to the building envelope, but perhaps because the heating systems are incorrectly adjusted or the ventilation flows are incorrect.

– But it could also be that some apartments have a poorer climate screen due to large leaks in or around windows, or that an office space has been converted into an apartment and that it has not been properly adapted to its real purpose.

– Then we have a lot of public clients, and then we talk about premises, such as hospitals or that we work with office premises where the staff feel that the climate is not good.

Which parameters affect the perceived indoor climate?

– These include air temperature, temperature from surrounding surfaces, humidity, which is measured with an IAQ sensor, and also air velocity, i.e. air movement in the occupied zone, which is measured with a draught sensor.

– The temperature of surrounding surfaces can be measured with a special type of sensor called a globe thermometer.

– You may also need to consider the thermal insulation capacity of clothing (clo-tal), metabolism (physical activity) and heat exchange between bodies.

How does an indoor climate analysis work?

– During an indoor climate analysis during the heating season with a testo 400 it is attempted when the outdoor temperature has been at zero or colder for at least three days. This will have an impact on all the different structures of the building.

– Measurements are taken and logged for 3 minutes at each measurement point, resulting in 180 measurement values from which the instrument can calculate PMV and PPD values, which gives a measure of how good the indoor climate is at each measurement point. It is also important that the instrument has had time to acclimatize for about 20-30 minutes before the measurement. So this is not something to be rushed.

– In parallel with the testo 400 measurement, all structures are also examined with a thermal imaging camera to see if there are any constructional deficiencies such as leaks or cold surfaces. Smoke is also released at expected cold spots such as cold exterior walls, windows and air leaks in facades to see how much “cold draft” there is or how leaky the building envelope is. Smoke is also used in larger zones where there is a risk of draught problems and, at the same time, all air flows and air movements in parts of the building where there are complaints are measured with different types of measuring instruments.

– They also measure the supply and exhaust air temperatures from the ventilation system to see how well it works. During the measurement period, it is also important to note external conditions such as outdoor temperature, wind direction, wind speeds, air pressure and whether it is overcast or sunny. There are many parameters that need to be taken into account when making measurements.

This IR image taken with a testo 872 shows that the plinth under the rebuilt window section only holds about 12-13 degrees at +3 degrees outside.

What is the interest in indoor climate?

– The interest of our clients actually seems to be increasing, I think. We have quite a few repeat customers and they understand the value of doing a proper investigation of recurring problems with the indoor climate. Usually, many problems can be eliminated by building technology, or it is a question of adjusting the heating or ventilation system.

At which points do the measurements take place?

– There is something called the occupancy zone , outside of which the criteria set do not apply. According to BBR (Boverket’s building regulations), the occupied zone is 0.1 meters above the floor up to 2 meters above the floor as well as 0.6 meters from walls and 1.0 meters from external limitations such as windows and doors.

– You never measure outside the occupied zone, because there you can never maintain the same climate that the building is designed for.

What are the requirements/standards for the right indoor climate?

– There are actually several claimants. For example, BBR, Boverket’s Building Regulations, current OVK regulations and AFS 2009:2 – Workplace design. In the case of complaints from tenants in apartments, you can also rely on the Public Health Agency’s guidelines.

What are the most common complaints that lead to an investigation?

– An indoor climate investigation usually starts with complaints from users, i.e. staff in offices or tenants in homes.

– Taking apartments as an example, the most common complaint is that it is too cold in some part of the apartment.

– If it is a workplace, it is common to find it draughty or cold. These faults are often caused by excessive airflow from the ventilation system or a leaky climate screen. During the summer, we may also be contacted to investigate when it gets too hot indoors due to a lack of shade.

What are the most common errors?

– Common faults can be neglected maintenance on windows, doors, damp facades, etc. or misadjusted heating systems or air flows. It could also be an incorrect construction of walls, windows, etc. for the workplace in question. Sometimes it can also be the case that a workplace has been set up in premises that are not at all fit for purpose, which poses major problems that need to be resolved.

– But the most common thing in premises is that you have incorrect airflows that are not adapted to the needs of the current activity, which often creates draft problems. If the caretaker takes the “easy” route, the supply air temperature of the supply air is increased, which makes things worse with a decrease in ventilation efficiency. People are easily chilled by excessive air movement. Based on this, it is therefore important that all airflows are adapted to the current activity when changes are made to all buildings.

Do you have an example of an investigation and what action was taken?

– A good example is when premises were converted into apartments in a governor’s house in Gothenburg about 10 years ago.

– A governor’s house is built of brick on the first floor, often on a granite base, with two floors of wood on top. So the technical conditions of the building envelope are completely different between the different plans.

– When the premises on the ground floor, which had previously been a tobacco shop and pizzeria, were to become apartments, problems arose after the move. The rebuild replaced all the large windows with a new insulated structure, but missed the plinth sections and the cold floors which had no insulation down to a cold cellar.

– The perceived indoor climate with these cold surfaces is not good, even if an indoor temperature of about 20 degrees is maintained. The operational temperature (perceived temperature) in these converted apartments was very low. Unfortunately, the tenants had to be evacuated after moving in and these eight apartments had to be rebuilt to achieve an acceptable indoor climate.

– A positive effect of this investigation, which led to further rebuilding, was that energy use was greatly reduced in the apartments and the tenants were satisfied with the indoor climate.

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Published 2024-06-04

The Church of Sweden Örebro Pastorate actively monitors the indoor climate in a large number of churches and office buildings. As part of this work, building technician Johan Asplund uses Celsicom loggers.

The pastorate aims to reduce heating costs by 15% – without sacrificing optimal climates for people, furnishings and equipment. This means that it should be +20 C° in offices, +18 C° in sacristy rooms and +13 C° in church rooms.

“Better control of metrics”
It is important that these temperature levels are maintained. Altar linens and vestments are sensitive to low temperatures (and high humidity, RH). The same applies to paintings, wooden sculptures and metal objects.
– With the help of the Celsicom loggers, we can have better control of different metrics,” says Johan Asplund.

Churches are temporarily heated
To keep energy costs down, some churches are not fully heated at all times. Instead, the heat is raised during church services and other ceremonies. The Celsicom logs give Asplund answers to how long before the heating needs to be turned up so that the right temperature is reached at the right time, and how the RH value in the church room is affected by time-limited heating.

Johan and his colleagues receive automatic alerts via SMS or email if limits are exceeded.

– This makes the logs particularly useful because the churches are so geographically dispersed. If I see that the temperature is about to drop a lot in a room, I can go there quickly and check if there is a problem with the power supply or if a radiator has failed.

Published 2024-06-25

Since 2016, energy engineer Billy Axelsson has been using data loggers from the Celsicom measurement system to remotely monitor various indoor climates in Kil municipality’s buildings. The loggers enable more efficient work and reduce energy consumption and the risk of costly breakdowns.

Billy Axelsson works at the property unit with responsibility for energy and ventilation. It is a small job considering that the municipality operates on about 60,000 square meters in about 50 buildings. These buildings house commercial kitchens, schools, nurseries, leisure facilities, care homes – and a range of other businesses.

An important part of the real estate unit’s work consists of remote monitoring of various climate parameters in different environments, in order to analyze important measurements on a daily basis and schedule measures or, if necessary, respond immediately. Measured variables such as temperature and humidity are monitored with data loggers from the first generation of the Celsicom measurement system (the loggers are connected to base stations) and data loggers from the second generation of the same system (these loggers have their own connection via the Narrow Band Internet of Things on their own frequency in the mobile phone network). In total, there are 107 measurement sites in 27 buildings.

Celsicom – an important backup
The fact that Celsicom was chosen eight years ago was mostly a coincidence.

– We have some comprehensive systems for monitoring and controlling heating and ventilation in our buildings. But I felt the need to have some kind of backup to be able to have continuous control and get alerts. “At one point I bought a thermal imaging camera from Nordtec and was a bit curious about what other fun things you had,” says Billy.

That’s when he discovered and chose to test Celsicom. Since day one, the remote monitoring system has greatly facilitated the work of the real estate unit. Above all, the ease of getting started and using the Celsicom logs is appreciated. The automatic limit alerts via SMS or email are also praised. And the fact that the purchase of each logger – including the subscription cost for storage and analysis in the Celsiview cloud service – is a modest investment.

Automatically alerts in good time
The real estate unit has found a variety of applications for the Celsicom loggers. Here are some examples of what they are used for.

– If a chiller breaks down or starts leaking refrigerant, the chiller can continue to run while the temperature starts to rise. This can quickly be seen from diagrams in Celsiview.

– Another great advantage is the possibility of receiving an alarm if, for example, a large meat fridge breaks down. Then you have to act quickly to avoid having to throw away goods worth SEK 100,000 the next day.

Celsicom loggers are also used in schools to ensure a good indoor climate in classrooms, to monitor temperature and humidity in music rooms and to prevent damage to stringed instruments. The remote monitoring also covers four pellet plants. There, Celsicom loggers simply alert you if pellet levels are approaching a critical level and it’s time to refill.

Preventing an expensive mishap
– I have also made a little invention of my own with one of the latest Celsicom loggers that has moisture ratio sensors (Celsicom MM611B). I’ve connected it to a screw in a wooden plank lying on the floor of a basement where we have very little supervision. And last winter there was a water leak from the heating system! I was alerted within an hour that the moisture content was too high in the wooden plank and was able to go there to quickly fix the flood and leak. It could have been really expensive if I hadn’t had that monitoring,” says Billy.

Celsicom also eliminates time spent traveling around checking conditions in different properties.

– Instead, I always have updated readings via the Celsiview cloud service on the home page of my computer. I can quickly see if something seems strange and can easily see how things are developing, and then decide whether I or someone else needs to go to the scene.

Good information and data
Celsiview is also a good tool for sharing information and providing input for various improvements. For example, staff in commercial kitchens can log in and have a ‘watch’ function to check temperatures in cold rooms and freezers in real time for their own control.

One of the property unit’s major challenges in the future is to make operations more efficient by, for example, reducing electricity and district heating. It’s about reducing energy use as much as possible without sacrificing a comfortable indoor climate. In this respect too, deployed Celsicom loggers are valuable tools.

– It is very easy to quickly see on your mobile phone, tablet or computer where the temperature is a bit too high and can be turned down to reduce heating costs. “In an electrically heated school that is in storage, I have Celsicom connected to the heating system to be able to keep the temperature as low as possible without it freezing in the winter,” says Billy Axelsson and notes:

– We save a lot of money by having sensors monitoring the radiator groups.