Unknown stuff on top of water heater
- Thread starter Yod12
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FingerLess
New Member
Looks like soot from the exhaust.
You can check if a candle flame is drawn toward the vent when the heater is on. Maybe your vent is partially blocked.
Get at least one CO detector. Defender makes some that alarm at really low levels.
Get at least one CO detector. Defender makes some that alarm at really low levels.
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"there should be 50 cubic feet of air per 1,000 BTUs required by the appliance" for adequate combustion air.
Opening an exterior door that is at first difficult & then you have an inrush of air means you have a slight vacuum in the house, so probably the "air balance" is not right. There is a local cafe that has this pretty bad, you can hardly open the exit door.
With more clues you can narrow down the root cause.
Opening an exterior door that is at first difficult & then you have an inrush of air means you have a slight vacuum in the house, so probably the "air balance" is not right. There is a local cafe that has this pretty bad, you can hardly open the exit door.
With more clues you can narrow down the root cause.
Jeff Handy
Well-Known Member
Sometimes replacing a conventional furnace that vents out the chimney with a high efficiency one that vents out of pvc will affect the water heater draft.
The furnace is no longer helping to create a strong chimney draft.
Also, using a range hood or bath fans can create negative air pressure in the house.
The furnace is no longer helping to create a strong chimney draft.
Also, using a range hood or bath fans can create negative air pressure in the house.
BvilleBound
Well-Known Member
A higher resolution photo would be helpful, but when I loaded your photo into Photoshop, zoomed in and optimized, the stuff on top of your water heater appears to be brown and granular -- similar to old vermiculite insulation. Check the opening above for the exhaust pipe, and see if this substance is on the surface. Also check your attic; it may have fallen down from above.
If your home does have vermiculite insulation, that would be an even bigger problem -- because vermiculite contains asbestos, a known carcinogen.
Mark
If your home does have vermiculite insulation, that would be an even bigger problem -- because vermiculite contains asbestos, a known carcinogen.
Mark
We have no idea what the exhaust pipe from the WH is connected to but it is likely run to a chimney that is used or was used for the homes heating. That chimney could have at one time been used for gas, oil even coal.
The WH does not run continually and will only draft properly when hot fumes are passing up it. The rest of the time if there isn’t something else sending heated gas up it there may or may not be a little draft.
Around here many homes have had their older gas furnaces replaced with high efficiency and the exhaust has been switched from a hot draft chimney to a fan driven PVC pipe exhaust out the side of the house. Now they have a massive brick chimney that only is there for the WH.
Strong winds can cause back drafts as can negative pressures from house exhaust fans. Homes used to breath but now windows, doors and insulating systems are sealed pretty tight and there is not a lot of makeup air. Drafty is not a word you hear a lot these days.
My guess is these crumbs are being back blown out of the chimney and likely accumulated on the lining of the flue over many years. I get gritty dust around mine as well not quite as bad and I wipe it off when I see it.
The WH does not run continually and will only draft properly when hot fumes are passing up it. The rest of the time if there isn’t something else sending heated gas up it there may or may not be a little draft.
Around here many homes have had their older gas furnaces replaced with high efficiency and the exhaust has been switched from a hot draft chimney to a fan driven PVC pipe exhaust out the side of the house. Now they have a massive brick chimney that only is there for the WH.
Strong winds can cause back drafts as can negative pressures from house exhaust fans. Homes used to breath but now windows, doors and insulating systems are sealed pretty tight and there is not a lot of makeup air. Drafty is not a word you hear a lot these days.
My guess is these crumbs are being back blown out of the chimney and likely accumulated on the lining of the flue over many years. I get gritty dust around mine as well not quite as bad and I wipe it off when I see it.
maxdad118
JOAMOS
Looks like stuff from the roof, clean it up and see if it reappears. Put your hand up close to the draft diverter while its running-you should not feel heat blowing back at your hand. If you do, your vent is misaligned or blocked.
