ᐅ Mechanical ventilation with heat recovery: where can I find independent information?
Created on: 18 Sep 2016 10:57
E
EinMarcHello,
today the topic is residential ventilation systems. Over the past few days, I have already done quite a bit of research here (and in other forums) on this subject, and I have also come across several information sites that seem obviously or less obviously lobby-driven. However, I somehow can’t find truly independent information...?
What stood out to me especially is that often in the comments on various blogs, dissatisfied customers express their frustration about systems that don’t work at all. Normally, I would suspect that those might be comments from the opposing lobby, but in this case, that doesn’t really seem to exist? Because the alternative would be ventilation through windows, and since one would never install non-openable windows anyway, it seems there is no generic interest group involved. Am I understanding this correctly?
What interests me about a controlled residential ventilation system:
-As a hay fever sufferer, filtered supply air would definitely be interesting.
-We hardly ever ventilate at the moment (the house is leaky enough anyway^^), and I’m worried it would be difficult to get used to doing this at least three times a day.
-My wife often works with larger amounts of adhesives (as a saddler), and I handle other chemical-smelling substances; continuous ventilation would be quite useful in those cases.
-We have four cats (indoors), so ventilating by opening windows regularly is quite inconvenient (having to shut them away and so on).
What I’m a bit concerned about regarding controlled residential ventilation:
-Are the same pipes always used? Because those flexible plastic spiral ducts don’t exactly inspire confidence when it comes to thorough (mechanical) cleaning.
-I know, at least, that industrial suction lines cannot be cleaned properly without mechanical cleaning. Is there even a possibility to mechanically clean the many long and narrow ducts in a controlled ventilation system? I’m thinking of devices similar to those used for drain pipe cleaning, but with rotating brushes or something like that.
-Often, despite controlled ventilation, I read about musty odors and insufficient air exchange. Are these just improper designs, faulty systems, or what went wrong there? How can I prevent that myself?
-Many people write that they retrofit exhaust air filters to avoid soiling of the exhaust ducts. Sounds reasonable, but is it that simple? Because that additional suction resistance wasn’t considered in the original system design.
-How can I know which provider and installer is sufficiently informed and experienced to ensure correct system design and installation?
Also, this “permanent” installation of the ducts doesn’t really appeal to me as a mechanical engineer. With such systems, access for potential maintenance and repair should actually be desirable, shouldn’t it? Are there options or solutions for this?
Maybe one or the other can share thoughts on my points or add other considerations?
Best regards,
Marc
today the topic is residential ventilation systems. Over the past few days, I have already done quite a bit of research here (and in other forums) on this subject, and I have also come across several information sites that seem obviously or less obviously lobby-driven. However, I somehow can’t find truly independent information...?
What stood out to me especially is that often in the comments on various blogs, dissatisfied customers express their frustration about systems that don’t work at all. Normally, I would suspect that those might be comments from the opposing lobby, but in this case, that doesn’t really seem to exist? Because the alternative would be ventilation through windows, and since one would never install non-openable windows anyway, it seems there is no generic interest group involved. Am I understanding this correctly?
What interests me about a controlled residential ventilation system:
-As a hay fever sufferer, filtered supply air would definitely be interesting.
-We hardly ever ventilate at the moment (the house is leaky enough anyway^^), and I’m worried it would be difficult to get used to doing this at least three times a day.
-My wife often works with larger amounts of adhesives (as a saddler), and I handle other chemical-smelling substances; continuous ventilation would be quite useful in those cases.
-We have four cats (indoors), so ventilating by opening windows regularly is quite inconvenient (having to shut them away and so on).
What I’m a bit concerned about regarding controlled residential ventilation:
-Are the same pipes always used? Because those flexible plastic spiral ducts don’t exactly inspire confidence when it comes to thorough (mechanical) cleaning.
-I know, at least, that industrial suction lines cannot be cleaned properly without mechanical cleaning. Is there even a possibility to mechanically clean the many long and narrow ducts in a controlled ventilation system? I’m thinking of devices similar to those used for drain pipe cleaning, but with rotating brushes or something like that.
-Often, despite controlled ventilation, I read about musty odors and insufficient air exchange. Are these just improper designs, faulty systems, or what went wrong there? How can I prevent that myself?
-Many people write that they retrofit exhaust air filters to avoid soiling of the exhaust ducts. Sounds reasonable, but is it that simple? Because that additional suction resistance wasn’t considered in the original system design.
-How can I know which provider and installer is sufficiently informed and experienced to ensure correct system design and installation?
Also, this “permanent” installation of the ducts doesn’t really appeal to me as a mechanical engineer. With such systems, access for potential maintenance and repair should actually be desirable, shouldn’t it? Are there options or solutions for this?
Maybe one or the other can share thoughts on my points or add other considerations?
Best regards,
Marc
I
Irgendwoabaier18 Sep 2016 11:16Hello,
from the first almost two years of operation of our system:
Supply air filter: yes, especially in very dry or dusty outdoor conditions, they get dirty quite quickly. Vacuuming them between replacement times makes sense under these conditions and is fairly easy and quick. We live right on the edge of a residential area, not far from farmland, so dust in the outside air or a few insects in front of the filter are to be expected.
Exhaust air filter: in my opinion, these are also necessary – the amount of dust that accumulates inside is quite high. On the one hand, the filter directly in front of the central unit (mainly affected by residue from the construction phase), and on the other hand, at the exhaust valves inside the house. It should be noted, however, that the first year showed significantly more dust than the following one.
Musty indoor air – we have not noticed this.
Strong odors indoors: well, with adhesives and other materials that emit strong gases, I would never rely on the standard ventilation system alone. Proper local exhaust extraction is necessary over the work area (think chemical lab – but that is not the role of a residential ventilation system), or work should be done outdoors.
Cleaning of the flat ducts as well as the riser ducts running inside the walls (round ducts): this should be possible since each individual pipe can be accessed at the manifold. But will it be necessary? As long as the supply and exhaust air filters are occasionally cleaned or replaced, it should not be required.
Best regards
I.
from the first almost two years of operation of our system:
Supply air filter: yes, especially in very dry or dusty outdoor conditions, they get dirty quite quickly. Vacuuming them between replacement times makes sense under these conditions and is fairly easy and quick. We live right on the edge of a residential area, not far from farmland, so dust in the outside air or a few insects in front of the filter are to be expected.
Exhaust air filter: in my opinion, these are also necessary – the amount of dust that accumulates inside is quite high. On the one hand, the filter directly in front of the central unit (mainly affected by residue from the construction phase), and on the other hand, at the exhaust valves inside the house. It should be noted, however, that the first year showed significantly more dust than the following one.
Musty indoor air – we have not noticed this.
Strong odors indoors: well, with adhesives and other materials that emit strong gases, I would never rely on the standard ventilation system alone. Proper local exhaust extraction is necessary over the work area (think chemical lab – but that is not the role of a residential ventilation system), or work should be done outdoors.
Cleaning of the flat ducts as well as the riser ducts running inside the walls (round ducts): this should be possible since each individual pipe can be accessed at the manifold. But will it be necessary? As long as the supply and exhaust air filters are occasionally cleaned or replaced, it should not be required.
Best regards
I.
Our experience with decentralized units (Sevi160):
- Cleaning is a bit annoying – filters need washing every 2 months
- Electricity consumption is very low (our total household electricity cost is about €32)
- I’m not sure about air quality – it doesn’t smell musty, but fresh (unlike in our previous two apartments)
- There is some noise – on setting 1, it’s easy to fall asleep (I am sensitive)
- Yesterday, we had a party with 14 people → it got warm, but on setting 4 (noise is less noticeable with background sound) the air quality was still good (you can tell when you go outside and come back in) – I found that quite impressive.
- Occasionally, outdoor odors are noticeable, but very rarely and faintly, mainly when someone is burning something and the wind is not favorable
- Humidity slowly adjusts to the absolute outdoor humidity
- Outdoor noises… if I hear something, I’m not sure if it’s not coming through our windows instead (not a big issue, it’s generally quiet here)
Great, thanks for the detailed answers! That already helps a lot.
I still have a question regarding humidity...
Since I work as a hobby with items that are very sensitive to rust, I’m a bit concerned about that. Is it possible to ventilate based on humidity levels? For example, keeping the basement relatively dry while maintaining normal ventilation in the rest of the house?
In my current workshop (a separate building), I have an air conditioning unit that I also use for dehumidification. Such a unit can be connected to a mechanical ventilation system with heat recovery as well. But with a mechanical ventilation system, wouldn’t all rooms be dehumidified?
Is it possible to control dehumidification selectively for individual rooms?
Or should/must I exclude the basement from the mechanical ventilation system? Then I could install a simple air conditioning unit there again.
I still have a question regarding humidity...
Since I work as a hobby with items that are very sensitive to rust, I’m a bit concerned about that. Is it possible to ventilate based on humidity levels? For example, keeping the basement relatively dry while maintaining normal ventilation in the rest of the house?
In my current workshop (a separate building), I have an air conditioning unit that I also use for dehumidification. Such a unit can be connected to a mechanical ventilation system with heat recovery as well. But with a mechanical ventilation system, wouldn’t all rooms be dehumidified?
Is it possible to control dehumidification selectively for individual rooms?
Or should/must I exclude the basement from the mechanical ventilation system? Then I could install a simple air conditioning unit there again.
Most central mechanical ventilation systems with heat recovery include humidity sensors, but these usually control humidity for the entire house. In general, people don't want the air inside the house to become too dry, as that can also be uncomfortable. However, controlled ventilation systems won’t make the air too humid either.
If you want a room to be particularly dry, you can isolate it from the controlled ventilation system by closing the vent and use a dehumidifier instead. These devices, which cost around 200 euros, can quickly reduce the humidity in a closed room to a very low level. I have one in my hobby/craft room that I sometimes turn on if needed.
If you want a room to be particularly dry, you can isolate it from the controlled ventilation system by closing the vent and use a dehumidifier instead. These devices, which cost around 200 euros, can quickly reduce the humidity in a closed room to a very low level. I have one in my hobby/craft room that I sometimes turn on if needed.
Similar topics