ᐅ Central ventilation system – is humidity recovery necessary?
Created on: 30 Dec 2019 16:17
L
ludwig88sta
Hello everyone,
for our planned single-family house with 2 floors and a basement, we have decided on a central ventilation system for all rooms with heat recovery within the thermal envelope. The brand and model are not yet determined.
I have read here on the forum a few times about an additional moisture recovery feature (MRF?), since otherwise the indoor air tends to become too dry (of course, the ventilation system also removes the moisture that naturally occurs in the room, which usually makes the air feel comfortable). I wanted to ask if anyone can confirm these issues and whether this is more common in timber frame houses or also occurs in brick houses?
Did you install additional moisture recovery in your ventilation system? How much extra cost does it involve? I assume there are also additional maintenance costs because it involves another motor and related components.
Best regards
ludwig88sta
for our planned single-family house with 2 floors and a basement, we have decided on a central ventilation system for all rooms with heat recovery within the thermal envelope. The brand and model are not yet determined.
I have read here on the forum a few times about an additional moisture recovery feature (MRF?), since otherwise the indoor air tends to become too dry (of course, the ventilation system also removes the moisture that naturally occurs in the room, which usually makes the air feel comfortable). I wanted to ask if anyone can confirm these issues and whether this is more common in timber frame houses or also occurs in brick houses?
Did you install additional moisture recovery in your ventilation system? How much extra cost does it involve? I assume there are also additional maintenance costs because it involves another motor and related components.
Best regards
ludwig88sta
tomtom79 schrieb:
Can’t every system do that? But reducing the air exchange rate and then saying the rooms won’t dry out is basically what we’re saying. Here’s a tip: just turn it off, then you’ll have over 50% and can ventilate manually again. Now, what’s gotten under your skin? There’s a big difference between “just turning it off” and an air exchange rate of 0.3/h. But if you think you absolutely need 0.5/h, feel free to set it that way. For normal use, 0.3/h is more than enough to keep the air fresh. If needed, you just use the “power boost” button to ventilate for 45 minutes. That way, you don’t even have to open windows—if you don’t want to.
To put it in your words: here’s a tip, just keep the controlled ventilation running at 100% capacity, then you’ll have even fresher air.
H
hausbauer5 Jan 2020 08:40In the pink forum, the user Leitwolf shares some interesting experiences with a CO2 sensor in the central exhaust system. During the day, the airflow is reduced if no high CO2 levels are detected (i.e., no one is at home). At night, ventilation runs continuously to prevent the bedroom from becoming stuffy. I am considering this as a supplement or alternative to the enthalpy exchanger.
face26 schrieb:
Very helpful post That’s why it doesn’t make sense, because a heat recovery ventilator clearly has advantages. The extent of these advantages could be debated. However, since this is about saving 300–500€ on an investment of over 500,000–700,000€ in my opinion it’s pointless. You could also discuss whether windows are really necessary or maybe just paint on the walls, where you can save much more.tomtom79 schrieb:
But without measuring the CO2 levels Who says I haven’t measured them? You are simply assuming things here. I just took a measuring device from work for a few days. Have you ever measured it yourself? Are you familiar with Pettenkofer? What do you do for a living?
Hausbauer schrieb:
In the pink forum, there are quite interesting experiences from the user Leitwolf regarding a CO2 sensor in the central exhaust system. During the day, the air volume is reduced if no high CO2 level is detected (meaning no one is home). At night, ventilation runs continuously so the bedroom doesn’t get stuffy. I’m considering this as a supplement or alternative to the enthalpy exchanger. That’s exactly what I already explained earlier with the timer program. Of course, having a permanently installed sensor also works. But with a simple timer and knowing when more air exchange is needed (at night, cooking times, and when all occupants are home simultaneously), everything works perfectly.
By the way: If CO2 levels were measured in some workplaces, many people would be shocked... what is being discussed here is simply laughable. (A single-family house with 4 people and an air exchange rate of 0.5/h supposedly required) Especially in meeting rooms or schools (which is really bad), the CO2 levels are on a completely different scale. Those are the places where we should really be paying attention.
If you have done something, please mention it—I cannot read minds. The problem is that people can misunderstand, that’s all I wanted to say.
No, I didn’t take any measurements. The air felt stuffy, that was noticeable, and our ventilation system only allows for 3 settings. I disabled the night setback. The ventilation runs constantly at level 2; to know the exact air exchange rate, I would have to check the calculations. If I were to build again, I would use both supply and exhaust air in the room without transfer openings, with the requirement to be able to regulate individual rooms.
No, I didn’t take any measurements. The air felt stuffy, that was noticeable, and our ventilation system only allows for 3 settings. I disabled the night setback. The ventilation runs constantly at level 2; to know the exact air exchange rate, I would have to check the calculations. If I were to build again, I would use both supply and exhaust air in the room without transfer openings, with the requirement to be able to regulate individual rooms.
Similar topics