DIY Home Improvement, Remodeling & Repair Forum > DIY Home Improvement > HVAC > Burning smell from heated painted PEX?




Help Support House Repair Talk by donating using the link above.
Reply
 
Thread Tools Search this Thread
Old 12-10-2016, 11:41 AM  
kmwest
Established Member
Join Date: May 2015
Posts: 33
Default Burning smell from heated painted PEX?

Our natural gas boiler is about 30-40 years old (manufactured 1987, first service sticker was 1994, so I assume about 35 years old). It's in our unfinished basement. A few months ago we had the entire basement (walls, floors, ceilings, exposed piping) painted and there is still a mild paint smell.

Since we started using the boiler this winter there is a light campfire smoky smell that starts going through the basement after the boiler's been running for 10-15 minutes. All the burner flames are blue and I just drained the expansion tank this morning due to it not maintaining water pressure and losing water from the TPR valve. We have a combination smoke/CO detector on the other side of the basement and it hasn't gone off.

This didn't happen last winter at all.

I might be imagining things but it seems to be most prevalent in the areas right under the hot water piping - both the PEX from the boiler and the hot water lines into our bathrooms and kitchen. I don't get as much of a smell from the boiler itself. Could this be from paint on the pipes, or the joists that they're on, heating up and creating fumes?

FWIW this smell dissipates when the boiler's been off. We turned the heat off overnight so I wouldn't scald myself in the expansion tank drain this morning, and there was no smoke smell. After I completed the drain, refill, and started the boiler again the smell started about 15 minutes later.

Thanks for any advice. I'm obviously concerned but don't want to worry unnecessarily.


kmwest is offline  
 
Reply With Quote
Old 12-10-2016, 11:50 AM  
Snoonyb
Senior Member
Join Date: Sep 2006
Posts: 2,264
Liked 397 Times on 352 Posts
Likes Given: 1

Default

Was the paint oil or water based?


__________________
Illigitimas non-carborundum
Snoonyb is offline  
 
Reply With Quote
Old 12-10-2016, 11:58 AM  
kmwest
Established Member
Join Date: May 2015
Posts: 33
Default

The floor paint was acrylic and latex... don't know about the ceiling paint that would cover the pipes, or about the primer.
kmwest is offline  
 
Reply With Quote
Old 12-10-2016, 02:17 PM  
Snoonyb
Senior Member
Join Date: Sep 2006
Posts: 2,264
Liked 397 Times on 352 Posts
Likes Given: 1

Default

Thanks.

You'll experience more out-gassing from oil based.

Is there any apparent discoloration above the appliance or on the pex near the source?
__________________
Illigitimas non-carborundum
Snoonyb is offline  
 
Reply With Quote
Old 12-10-2016, 02:56 PM  
kmwest
Established Member
Join Date: May 2015
Posts: 33
Default

Quote:
Originally Posted by Snoonyb View Post
Thanks.

You'll experience more out-gassing from oil based.

Is there any apparent discoloration above the appliance or on the pex near the source?
None that I can tell. I can post photos but nothing looks discolored - but it is black paint on the ceiling. What do you think may be an issue?

I just went back into the basement and the boiler is cold now that the house is back up to programmed temperature. No smell in the same place that had it the worst earlier.

Edit: my arithmetic is bad, the boiler is about 25-30 years old since it was made in 1987.
kmwest is offline  
 
Reply With Quote
Old 12-10-2016, 04:06 PM  
Snoonyb
Senior Member
Join Date: Sep 2006
Posts: 2,264
Liked 397 Times on 352 Posts
Likes Given: 1

Default

Any discoloring will probably began to appear as toward the brown area of the spectrum.

I would monitor it for a week, for a gradual dissipation of the odor, which should occur as the "baking-in" of the paint continues.
__________________
Illigitimas non-carborundum
Snoonyb is offline  
 
Reply With Quote
Old 12-10-2016, 05:03 PM  
kmwest
Established Member
Join Date: May 2015
Posts: 33
Default

Quote:
Originally Posted by Snoonyb View Post
Any discoloring will probably began to appear as toward the brown area of the spectrum.

I would monitor it for a week, for a gradual dissipation of the odor, which should occur as the "baking-in" of the paint continues.
So any discoloration would just be due to the heat onto the paint? Or another issue?
kmwest is offline  
 
Reply With Quote
Old 12-10-2016, 06:52 PM  
Snoonyb
Senior Member
Join Date: Sep 2006
Posts: 2,264
Liked 397 Times on 352 Posts
Likes Given: 1

Default

Yes, if it occurs at all, it will be over time and if the paint was a flat you may, over time, notice a shading effect.
__________________
Illigitimas non-carborundum
Snoonyb is offline  
 
Reply With Quote
Old 12-10-2016, 09:45 PM  
slownsteady
Administrator
HRT_ADMIN.png
 
slownsteady's Avatar
Join Date: Jun 2009
Location: Newton, NJ
Posts: 6,299
Liked 1109 Times on 919 Posts
Likes Given: 1826

Default

Could also just be burning off accumulated dust after sitting idle for the summer. Is this the first time you're using heat this winter (fall)? AS Snoonyb said, watch things and see if the smell dissipates over time.
__________________
Learn something every day
---
SnS
slownsteady is offline  
 
Reply With Quote
Old 12-11-2016, 08:26 AM  
Snoonyb
Senior Member
Join Date: Sep 2006
Posts: 2,264
Liked 397 Times on 352 Posts
Likes Given: 1

Default

Yep! In retrospect and it's because I automatically do a routine cleaning at the start of every heating season, another issue would be, had a general cleaning been accomplished prior to firing up the appliance.


__________________
Illigitimas non-carborundum
Snoonyb is offline  
 
Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Similar Threads
Thread Thread Starter DIY Home Repair Forum Replies Last Post
Kenmore 800 electric dryer burning smell Averagejoe84 General Appliance Discussion 5 06-09-2016 11:56 AM
Burning smell Gas Dryer christymstwo General Appliance Discussion 1 03-10-2013 02:44 PM
LG dryer -- not turning/burning smell yada General Appliance Discussion 3 11-04-2011 09:25 PM
Heated floors in bathrooms FlashGIV Flooring 3 01-06-2010 12:31 PM
Heated towel bar jgmorten General Home Improvement Discussion 0 05-16-2008 10:57 AM



Newest Threads