Energy Recovery Ventilator (ERV)

[canopy]

Anyone have experiences, suggestions, or sources for getting an ERV for a house?

 

[sometimewoodworker]

10 minutes ago, canopy said:

Anyone have experiences, suggestions, or sources for getting an ERV for a house?

There is a posting on CTH of someone who has recently installed one in his energy efficient build near Surin.

Edited January 14, 2020 by sometimewoodworker

[VocalNeal]

Is there sufficient in/out temperature difference here? In,say, Canada there is say +20C to -20C (40C diff) but in the tropics?

Here it is mostly about humidity.

Edited January 14, 2020 by VocalNeal

[canopy]

1 hour ago, VocalNeal said:

Is there sufficient in/out temperature difference here?

Read up on them. Ideal for homes in warmer climates with mild winters, a ERV transfers moisture and heat from incoming fresh air to the outgoing air stream. I like the idea of running them in the evenings, expelling the warm air out of the house and replacing it with cooler, fresher outside air. And fitted with a high quality filter they also work as a whole house air purifier. Much better than just opening the windows letting all the noise and smoke inside.

 

Edited January 14, 2020 by canopy

[VocalNeal]

OK i understand having a filter at one end on a space and an exhaust fan at the other for air change, up north if it is cooler. I just don't see the energy recovery bit working in Thailand. If my physics memory is correct the rate of heat exchange depends on the difference in temperature. Here the difference between inside and outside is not so great. Maybe 10-12C. 

 

I don't live in Chiang Mai so my experience is not related to having to keep smoke out of the house.

 

 

[canopy]

If you aren't sure how they work then why not read up on them? Excellent information is easily found online from experts. You will find ERVs are well suited to Thailand's climate.

 

 

[sometimewoodworker]

2 hours ago, VocalNeal said:

I just don't see the energy recovery bit working in Thailand.

Cool dry conditioned air inside, hot humid air outside.
 

If you just ventilate you have to cool and dehumidify the incoming fresh air.

 

Use an ERV system and your AC has less work.

[mogandave]

As I understand it. ERVs are generally used to cool (or heat) make-up air. 
 

They are popular In systems where regulation mandate a percentage of the air being released into a building is “fresh”. 
 

It in a HVAC system, introducing outside air uses a lot of energy. The ERV uses the cool (or warm) inside air to cool (or heat) the outside make-up air as it is introduced into the system.
 

The greater the inside-outside temperature differential the more effective they are. Ruskin builds a good ERV and they have a decent website.

 

 

[tjo o tjim]

You want to find one with an enthalpy/dessicant wheel to transfer the humidity back outside.  A simple recuperator won’t do enough to make it worthwhile; you will need at least a 5C dry bulb difference to get any heat transfer.