AC Air

[am9518]

I have a Rheem Classic 90 Plus that's 9 years old. When I run the AC and my neighbor is burning leaves the smoke is pulled into my house via the PVC pipes that run outside my house. I noticed that if I cover one of the two PVC pipes that HVAC system uses I don't get the smell in the house but I also don't get any air pressure from the AC. Is this normal for HVAC systems to draw in outside air or is my Rheem crappy or malfunctioning? I've had a local company (Bel-o) service it twice a year. Thanks in advance for your help!

[NCHeat]

The PVC pipes should have nothing to do with tha A/C function

[ar_hvac_man]

Wierd. Where does the pipe that you cover up land on the unit?

[Mr Bill]

The PVC pipes should have nothing to do with tha A/C function

If he has an electric air handler, and it has no trap and it's run outside, it's very possible to draw the smoke onto the home.

[ar_hvac_man]

Its a 90+ furnace i believe. If they didnt run a concentric vent then the HO will have an exhaust and a combustion air intake.

I dont see how covering either of them would cause a loss of airflow.

Covering fresh air intake, if there is one, shouldnt kill the air flow either

[Mr Bill]

Its a 90+ furnace i believe. If they didnt run a concentric vent then the HO will have an exhaust and a combustion air intake.

I dont see how covering either of them would cause a loss of airflow.

Covering fresh air intake, if there is one, shouldnt kill the air flow either

Yes! been a long busy day, I should read the fine print. :grin2:

[am9518]

Thank you! I put temporary pvc caps on the outside. That got rid of the smokey smell and didn't seem to reduce the airflow very much. Thanks again for the quick reply!

[ar_hvac_man]

Honestly my first thought was a trapless drain too lol. 13 hrs today and its only april.

[am9518]

The pipe that I had initially temporarily covered was on the right side of the unit. I couldn't access the other PVC pipe inside the unit (on the left).

So is there any way I can put an air trap of some kind to keep outside air out? I really don't like putting temporary caps on the PVC outside of my home and have to remember to remove the caps when I switch the heater on.

[ar_hvac_man]

am9518 how big are the pvc pipes you capped? 2-3 inches or 1 inch?

again, neither of those bigger pipes should introduce outside air into your airstream.

[hvacman14]

i would have the heat exchanger checked, sounds like it may have a crack or opening in it, and as the fan blows across it, it some how is causing a negative pressure in it pulling in the smokey outdoor air, i know its a far fetched idea but stranger things have happened,

[am9518]

the pipes are 2in on the outside of the house. On the inside of the house both pipes are 3in and then get reduced back to 2in as they go into the Rheem. Thanks for the heat exchanger suggestion!

[ar_hvac_man]

The seals on the access panels could be bad too. Id have it checked.

[am9518]

Thanks for the seals suggestion too! I appreciate the help!