Water Heater problem

Specific Inspection Topics Plumbing Inspections
1

Inspected this water heater today. Everything seemed fine except for the discoloration around the burner access panel. I turned the heat up to get the heater going, no problem. No rust, great flame. Let it burn for about 2 minutes and turned the temperature back down to previous setting.

As I put the access panel back on, the edge of the opening was extremely hot. All around the tank at burner level I took a digital thermometer reading. normal, around 104. At the door opening, it went up to 212 and thus the discoloring.

Flame looked normal as did everything else. Any thoughts on the cause?

Steve

2

Was the flame shield off while you were inspecting?

What is that a pile of carpeting against the appliance and carpeting on the floor also?..:shock:

http://www.americanwaterheater.com/support/bulletins/TA_5001.pdf

3

The shield was on when I started inspection. I had the shield off to inspect but the discoloration was already there. The carpet was stored in that closet with tons of other stuff. Notice the melted backing on the carpet?

4

Steve

It looks like a backdrafting issue…whatever might be causing it.

http://oikos.com/library/energy_outlet/backdraft.html

5

But then again, an older heater will look like that anyway…but it looks fairly new.

6

Stephen,

What about the gas line? From the pic, there is no drip leg? Just wondering.

7

This is commonly referred to as “flame rollout.” There can be several causes - inadequate combustion air and venting issues (like backdrafting or a missing vent cap) are the most common causes.

However, if the heat shield is properly in place, rollout should not occur, even with one of the previous conditions present.

A large percentage of heat Shields are not properly installed. I would bet that this was the problem.

8

Ditto Jeff’s post.

9

Some manufacturers use an inner and outer heat shield. The inner may be missing. But yeah, what Jeff said. I’d call it out for “flame rollout”.

10

Flame rollout in this closet would most likely start a house fire. I would tell the client / H.O. get that stuff out of there for safety’s sake…:frowning:

A partially block internal “flue” within the water heater can also cause flame roll out plus excessive debris on the burner can also influence flame pattern . What this is to me is heat coming from the gap where the metering valve gas line enter to the burner.
I see this once and a while. Flame rollout would have more of a pronounced pattern on the outter jacket . Possible melting of the tag on the flex gas line and soot on the outer jacket would be visible. The outer cover (blue) is acting as a “channel” to deflect the heat at that point. Notice the concentration of the heat marking behind the gas metering valve lines? I would also check if this water heat is designed for closet installation too. Many times enclosing these Cat 1 natural draft appliances in a closet is not a good idea.

Did you check for flue draw ?