Need help with Aldehyde exhaust smell

[lee42048]

I have a Bryant Plus 90 that is over 20 years old. I noticed Aldehyde exhaust smell and discovered the main gas valve was pulsing on and off. I replaced the flame sensor and fixed the valve problem and figured that would solve the smell it but it didn't. The smell is not as strong, but still too much.

The general operation seems to be normal. The gas valve now works correctly. I have cleaned out both the intake and exhaust PCV pipe and they are clear. The combustion blower seems to be running steady. I have seen the burner flames cycle from blue to yellow and back during what should be a normal run. The combustion chamber is sealed and the only cleaning I can do is of the burner assembly which I have done. The water output seems normal inside. The installer pitched it badly and I can get quite an ice sculpture outside. I run on city natural gas. It also seems to take longer to raise house temperature than it should. What am I missing?
Thanks

[Chris_Worthington]

I have a Bryant Plus 90 that is over 20 years old. I noticed Aldehyde exhaust smell and discovered the main gas valve was pulsing on and off. I replaced the flame sensor and fixed the valve problem and figured that would solve the smell it but it didn't. The smell is not as strong, but still too much.

The general operation seems to be normal. The gas valve now works correctly. I have cleaned out both the intake and exhaust PCV pipe and they are clear. The combustion blower seems to be running steady. I have seen the burner flames cycle from blue to yellow and back during what should be a normal run. The combustion chamber is sealed and the only cleaning I can do is of the burner assembly which I have done. The water output seems normal inside. The installer pitched it badly and I can get quite an ice sculpture outside. I run on city natural gas. It also seems to take longer to raise house temperature than it should. What am I missing?
Thanks

A CO monitor "AND" a visit by a pro :D

These had a lifetime warranty on the heat exchangers,,,,, shut it down,,,and,,, call someone!!!!!!!!!!!!! :D

[dannyromans]

If there is any water around or in the blower compartment, you probably busted your secondary heat exchanger. The smell is a giveaway

[lee42048]

I forgot to say the smell is outside only.
There is water in the blower compartment. I thought I spilled something.
Thanks now I know for sure the exchanger is broken.

[pauls heating &]

If there is any water around or in the blower compartment, you probably busted your secondary heat exchanger. The smell is a giveaway

w the smell..likely secondary hx

[big sky hvac]

I forgot to say the smell is outside only.
There is water in the blower compartment. I thought I spilled something.
Thanks now I know for sure the exchanger is broken.

Even though it may have a lifetime warranty on the heat exchanger, you're still going to have to pay the labor to have it replaced. At 20 years of age, I'd recommend replacing the furnace rather than repairing it. General life expectancy of a furnace is 15-20 years, so it's had a good life. A new furnace would be investing your money more wisely than repair your old one, IMO.

[Chris_Worthington]

Well seems like the consensus here is to TURN IT OFF and CALL SOMEONE !!

:payattention:

Really no one here is trying to freak you out, but it sounds like it ain't safe, so,,,,, get busy with it and get it addressed :D

[lee42048]

I will, I promise.
I found out the exchanger is under warranty but the labor is not. Since I am not a Bryant dealer and therefore can not get an exchanger I will have to pay a dealer to install it.

[big sky hvac]

I will, I promise.
I found out the exchanger is under warranty but the labor is not. Since I am not a Bryant dealer and therefore can not get an exchanger I will have to pay a dealer to install it.

You're not really considering replacing the heat exchanger are you? I don't think that would be the best way to spend your money. I don't know what other repairs have been made to your furnace, but at 20 years old, other components are going to start failing. You'd hate to spend a bunch of money on a new heat exchanger and then have the blower motor crap on you a couple of months down the road. If I were you, I'd replace the furnace, that would be money well spent. In the meantime, you might consider sleeping with the window open in your bedroom to ensure you'll wake up in the morning.

[Ghostrider67]

I would shut it off ASAP. Yellow flames mean CO! Start shopping. There are alot of good units out there. Good luck.

[polar ice]

Seen it before...units done. Why gamble with it. New is new.