Balancing heating and ventilation in hospitals

Published 2022-08-11

Operation technician Martin Lundin works with the indoor climate at the hospital in Västerås but also at the hospitals in Fagersta, Sala and Köping in Region Västmanland. His constant challenge is to create comfortable indoor environments for both healthcare professionals and patients while keeping energy consumption low.

To help him in his daily work, Martin Lundin often uses the smart multi-instrument testo 400. Nordtec caught up with Martin to hear about his impressions and experiences with this climate meter.

Can you tell us a bit about your work?
– I do everything in the field of indoor climate and check ventilation flows and also perform some minor adjustments. However, as we have about 400 000 square meters to cover in our premises, much of this work is done by hired contractors.

– I am also an energy coordinator. In this role, I work actively to reduce energy consumption, which is measured in kilowatt hours per square meter.

– Also, you should not feel that there are temperature differences between different hospital departments, but it can be difficult to find that balance. However, the instrument is great for walking around and measuring temperatures and also differential pressure between different corridors, i.e., the air conditioning system. over- or under-pressure to ensure the right balance of ventilation systems.

– I also work on preventive maintenance. To enable my staff to easily troubleshoot when we have problems with heating or ventilation, I have equipped them with a bag containing the testo 440 multi-instrument and various accessories. Good work always requires good instruments and tools.

Do you measure both in premises and ventilation ducts?
– Yes, exactly. I measure temperature, humidity and airflow in ducts and premises. When measuring flow in canals, I sometimes have to drill a hole and measure at several points in a cross section of the canal area.

You mean so-called grid measurement?
– Yes, that’s right. That’s where the instrument is fantastic. You specify whether it is a square channel, for example, enter the dimensions and then take a number of measurement points. The instrument then automatically calculates the airflow.

Are you satisfied with the instrument?
– I’m super happy. I had a testo 440 dP before, but needed an instrument with better pressure measurement accuracy and the ability to log trends. There are so many more possibilities with the testo 400.

Do you feel unfamiliar with a touch screen on a measuring instrument?
– No, given today’s technology and how accustomed we are to mobile phones, it was quite natural. On the contrary, it was very easy to get started with the testo 400.

How do you analyze the measurement results?
– I usually connect the instrument to the computer and use the program testo DataControl to analyze the values. Then I get reports that are very useful where I can also attach pictures. I think that’s really good.

Can you tell us about a particularly interesting measurement mission?
– Yes, in Sala hospital we changed the control equipment on an old unit to get better control of the supply air temperature. But initially there was too much alternation between high and low temperatures.

– Then we were able to use the 400, because we could connect both before and after the heating coil. The controller’s P and I times were changed and we could continuously see how it calmed down or if the values jumped. You could see when it started to oscillate. That’s where the trend management in testo 400 is fantastic.

– Then I am currently working on mapping the indoor temperatures of the entire hospital, in all departments at different outdoor temperatures.

That sounds like a big job?
– Yes, our client requires that energy consumption be reduced, so we have a huge job ahead of us to get the right curves, especially on the heating side and to have the right temperature in the supply air.

What did you use before getting the testo 400?
– Previously, as I said, I had a testo 440. But I needed better accuracy of the differential pressure measurement at low air flows. Also, I like to see trends, which cannot be done in the same way with this instrument.

What kind of sensors do you use?
– I have a small hot wire sensor that is always in the instrument. Then I have a digital sensor that measures both moisture and temperature. These values are transmitted to the instrument via Bluetooth. Both these sensors also work with the old testo 440. Then I have a clamp-on sensor for pipe temperature measurement as well.

What did you use before getting the testo 400?
– Previously, as I said, I had a testo 440. But I needed better accuracy of the differential pressure measurement at low air flows. Also, I like to see trends, which cannot be done in the same way with this instrument.

Have you needed support from us to get started?
– No, I think it has worked well. The only thing that happened was that the pipe temperature sensor broke on one occasion.

Do you also use data loggers to see trends over time?
– Yes, I do if I am unsure and there are major problems that are not immediately apparent. Then I have to log for a longer period of time and analyze the anomalous trends afterwards.

Do you have any requests, anything you would like to see in the instrument?

– I don’t know… I haven’t used exactly all the features yet, but right now I’m just very happy with the instrument!

– If one could wish freely, it would have been good to have a socket at the top of the front for a hot wire sensor. He often holds the instrument upside down.

– Then it would be good if you could make a few more pre-settings in the instrument via the analysis program testo DataControl.