4 ms·

I'm having a very similar experience with indoor air quality in winter. Googling ERV doesn't deliver anything. What would I look up to find what you're talkin

I'm having a very similar experience with indoor air quality in winter. Googling ERV doesn't deliver anything. What would I look up to find what you're talking about?

xyzelement 3y ago
It stands for "energy recovery ventilator" - in a nutshell it just blows fresh air into your house and exhausts stale air, but uses the heat in the exhaust air to warm up the incoming air so it's more comfortable and energy efficient compared to an open window with a fan in it. Before you go too far that route (a multi-thousand dollar install) I recommend getting an indoor air quality meter to get a sense of what might be the problem. I recommend the Airthings View Plus, which is about $300 but is comprehensive and reliable and since (in my case) I made a multi-thousand dollar decision based on it, it was worth the investment. In my house it was obvious there's a massive CO2 buildup, CO2 itself isn't as big a deal itself but an indicator of stale air (ie, it's not being vented out by itself) and somewhat elevated radon. The ERV isn't the "prescribed" solution for radon but since it ends up venting it out it's fine. One last thing - for me, the connection between energy and indoor air quality was obvious in retrospect. I could wake up early and be miserable, but once I stepped outside to take my son to school I'd feel better. Or vice versa - I could be full of energy running around all day, then come home and immediately get drowsy. It only took about 15 years to realize indoor air was the cause.
- gilbertbw 3y ago
  This is called MVHR (mechanical ventillation with heat recovery) in the UK. We're looking at putting it in, but have a fairly poorly insulated house, so it's not clear if the heat recovery is worthwhile. There is also PIV (positive input ventillation), which blows fresh air into a property (normally the hallways), but does not recover heat, or duct air from the rooms. So it's much simpler and cheaper to buy and install. It relies on the natural 'leakiness' of the property to vent stale air out.
  - xyzelement 3y ago
    // This is called MVHR (mechanical ventillation with heat recovery) in the UK. These are actually two subtly different things. ERV (what I am talking about) recovers some of the moisture content along with heat, while an HRV (heat recovery ventilator and probably what you're talking about) does the heat but not the moisture. Depending on where you live this matters or doesn't matter (eg, if your winters are really dry and/or your summers are really humid, you want the ENERGY recovery ventilator to keep the house humidity closer to what you want vs equalizing with the outside. // We're looking at putting it in, but have a fairly poorly insulated house, so it's not clear if the heat recovery is worthwhile This doesn't make sense to me at all. First, if your house is "leaky" then why do you need mechanical ventilation at all, versus just relying on the natural air exchange (I can think of a valid reason but just curious how you think about it.) Second, if you DO put it in, your house is obviously better conditioned inside compared to outside so why wouldn't you want to recover that heat, at least for comfort if not economy? // There is also PIV (positive input ventillation), which blows fresh air into a property (normally the hallways) Yut but I think your hallway is then going to be as cold as the outside in the winter?

I'm having a very similar experience with indoor air quality in winter. Googling ERV doesn't deliver anything. What would I look up to find what you're talking about?

xyzelement 3y ago

It stands for "energy recovery ventilator" - in a nutshell it just blows fresh air into your house and exhausts stale air, but uses the heat in the exhaust air to warm up the incoming air so it's more comfortable and energy efficient compared to an open window with a fan in it. Before you go too far that route (a multi-thousand dollar install) I recommend getting an indoor air quality meter to get a sense of what might be the problem. I recommend the Airthings View Plus, which is about $300 but is comprehensive and reliable and since (in my case) I made a multi-thousand dollar decision based on it, it was worth the investment. In my house it was obvious there's a massive CO2 buildup, CO2 itself isn't as big a deal itself but an indicator of stale air (ie, it's not being vented out by itself) and somewhat elevated radon. The ERV isn't the "prescribed" solution for radon but since it ends up venting it out it's fine. One last thing - for me, the connection between energy and indoor air quality was obvious in retrospect. I could wake up early and be miserable, but once I stepped outside to take my son to school I'd feel better. Or vice versa - I could be full of energy running around all day, then come home and immediately get drowsy. It only took about 15 years to realize indoor air was the cause.

gilbertbw 3y ago
This is called MVHR (mechanical ventillation with heat recovery) in the UK. We're looking at putting it in, but have a fairly poorly insulated house, so it's not clear if the heat recovery is worthwhile. There is also PIV (positive input ventillation), which blows fresh air into a property (normally the hallways), but does not recover heat, or duct air from the rooms. So it's much simpler and cheaper to buy and install. It relies on the natural 'leakiness' of the property to vent stale air out.
- xyzelement 3y ago
  // This is called MVHR (mechanical ventillation with heat recovery) in the UK. These are actually two subtly different things. ERV (what I am talking about) recovers some of the moisture content along with heat, while an HRV (heat recovery ventilator and probably what you're talking about) does the heat but not the moisture. Depending on where you live this matters or doesn't matter (eg, if your winters are really dry and/or your summers are really humid, you want the ENERGY recovery ventilator to keep the house humidity closer to what you want vs equalizing with the outside. // We're looking at putting it in, but have a fairly poorly insulated house, so it's not clear if the heat recovery is worthwhile This doesn't make sense to me at all. First, if your house is "leaky" then why do you need mechanical ventilation at all, versus just relying on the natural air exchange (I can think of a valid reason but just curious how you think about it.) Second, if you DO put it in, your house is obviously better conditioned inside compared to outside so why wouldn't you want to recover that heat, at least for comfort if not economy? // There is also PIV (positive input ventillation), which blows fresh air into a property (normally the hallways) Yut but I think your hallway is then going to be as cold as the outside in the winter?