I recently finished my retirement home. It is heavily insulated, air-tight with new rooftop solar panels and is very energy efficient. The problem is it’s so airtight that the C02 levels (that’s carbon dioxide NOT carbon monoxide) are very high. Background C02 level is 480ppm (that’s outside) in the house with just me in it the levels get up to 2000ppm.
I have two bath fans that will each move 110 CFM of air outside. I want to get a C02 sensor and have it start the fans when the C02 levels get above 1000ppm. The long-term answer is to install an ERV (energy recovery unit) that will provide constant fresh air exchanges in the house. It is only an issue in the winter when the windows are closed. Apparently, I built the house too tight.
I am looking for co2 sensors that I can use as triggers to start building exhaust. Everything Presence makes a few sensors that look great unfortunately my protocol is Z wave and they run on Zigbe. Any info on quality C02 sensors for smart home applications (preferably that work on Z wave) would be appreciated. My ultimate goal is to manage the indoor air quality by starting and stopping exhaust and make up air fans.
Sounds like my parents in law’s situation. Reminds me that I should get them a CO2 sensor, because the air is always bad and I have to tell them that they should open a window - they are very old.
I’m very happy with the IKEA ALPSTUGA (Matter over Thread) and I’m using them to turn on fans when the level is above 1200 ppm.
First I have to declare that I have no specific knowledge in this area.
But with a very airtight house you need some sort of external air circulation with a heat exchanger rather than just a bathroom extractor fan.
Agreed, a CO2 sensor is still a good idea.
Just my thoughts.
I said in my posting that I was planning on installing an ERV but that’s a lot of work involving sheet metal duct work and $$$. So for now I looking for a short term work around.
We have a Net-Zero home, built pretty much the same way: highly insulated, air-tight (it got a great reading on the test with the big fan covering the front door & measurement of the pressure differential between inside/outside) and solar panels on the roof.
Our place was built with an HRV or Heat Recovery Ventilation System. It’s more complex than a simple ventilation system, as it pre-heats (winter) or pre-cools (summer) incoming air with a heat exchanger between the incoming and outcoming air. It’s not perfect, but pre-heating/cooling the air is part of the idea.
Anecdotally, one of our neighbors (the entire development was built as Net-Zero homes) who had chronic respiratory issues stated that since she lived here in her new home, she hasn’t had any issues or required hospitalization. We’ve noticed that cooking smells, etc., dissipate rather quickly. Our HRV is set currently to run 20 minutes out of the hour.