I have relatively new 2010 Bryant 60,000 BTU 95% efficient furnace (Model - 355CAV042060 ). The problem I see is that when ever the furnace starts up the CO2 levels within the house start rising.
I recently installed a couple of CO2 and Temperature sensors in the house. They essentially log the CO2 and temperature every few seconds have a nice web interface that plots value over time on a X/Y plot ( see attachment).
I noticed that when ever the furnace turns on the CO2 levels rise in tandem. The CO2 levels in the house increse by 150- 300 PPM ( In case the furnace has a longer run - the levels go up to 2000 PPM ( max recorded). The furnace typically cycles every 30 - 40 min depending on how cold it is. The above CO2 levels are not hazardous - but I am stumped as to why the CO2 levels are rising in the first place as the furnace exhaust is getting properly vented. I have the company that installed the HVAC coming out to take a look - but they are equally stumped.
1> The CO2 levels in the furnace closet do not rise - They stay steady at around 500 PPM. Whcih tells me that the CO2 from combustion is getting vented out and is not being released the closet ( the intake vent is out side the closet)
2> I tested the sensors they are running fine and record ambient CO2 outside the house in the 450 PPM range.
Any thoughts on what we should be looking for? The furnace has been lightly used over the last 5 years ( This section of the house was unoccupied )
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I recently installed a couple of CO2 and Temperature sensors in the house. They essentially log the CO2 and temperature every few seconds have a nice web interface that plots value over time on a X/Y plot ( see attachment).
I noticed that when ever the furnace turns on the CO2 levels rise in tandem. The CO2 levels in the house increse by 150- 300 PPM ( In case the furnace has a longer run - the levels go up to 2000 PPM ( max recorded). The furnace typically cycles every 30 - 40 min depending on how cold it is. The above CO2 levels are not hazardous - but I am stumped as to why the CO2 levels are rising in the first place as the furnace exhaust is getting properly vented. I have the company that installed the HVAC coming out to take a look - but they are equally stumped.
1> The CO2 levels in the furnace closet do not rise - They stay steady at around 500 PPM. Whcih tells me that the CO2 from combustion is getting vented out and is not being released the closet ( the intake vent is out side the closet)
2> I tested the sensors they are running fine and record ambient CO2 outside the house in the 450 PPM range.
Any thoughts on what we should be looking for? The furnace has been lightly used over the last 5 years ( This section of the house was unoccupied )
