Garage heat/home system

[dtortoise9]

I have been told that you cannot install a heater/cooling duct line from the house to the garage (heat pump system). If the return registers are in the house only, then what exactly is the problem? Again I am not an expert here and I am just trying to learn the reason why . I know I can do a mini split and keep them separate.

 

[PoorUB]

You do not want to mix air from the house and garage. Possibility of getting carbon monoxide in the house. Just don't do it!

Also if you blow air from the house into the garage you will have a negative pressure in the house and positive pressure in the garage, more chance of carbon monoxide.

Fire problems too. The duct will be a possible hole in the wall for fire to move from the garage to the house through the duct.

 

[dtortoise9]

Thank you for your reply.

 

[American Locomotive]

Basically even without a return, the air will sneak its way back into the house through cracks, doors, gaps, etc... Or if the furnace is off, there is still a possibility of carbon monoxide traveling through the vents.

 

[toyotadriver]

The probability of it ever being a problem is incredibly small. The problem is, if it ever does happen (even if the probability is very low) the consequence of it is death potentially to everyone in the home.

Just keep separate systems.