Water heater has stumped 2 plumbers and 2 hvacs

[tmhinworks]

My new Bradford White has been a stinker, and I'm hoping some advice here will point me in the right direction.

Brand new Bradford White 50-gal natural gas (RG1506TN).
- From the day it was put in, the (red) thermal switch started tripping and kill gas to the pilot. It would run between 1 to 48 hours between trips.
- Installed in a very well-ventilated area. Fresh air intake behind the unit, and an open door into a daylight basement.
- The thermal switch trips less often if the heat is set lower (under 120f).
- Only seems to happen when on pilot (not under heat).
- The pilot never puts itself out (e.g. downdraft), it's always a result of a thermal trip.
- I don't notice any substantial orange tips on the flame; it seems very blue, but it's hard to see the tops with this model.
- The kicker: The thermal switch will never trip if I have a box fan pointed in toward the room.

What has been tried:
- Plumber switched out the gas valve (full assembly w/thermopile) and replaced the red thermal switch. They said they had gotten some bad switches in, and replacing them has been working. But not for mine.
- Plumber checked gas into the valve, all the way through to the pilot and burner assembly.
- Gas company checked gas pressure and the line coming in.
- HVAC checked venting. This shares a flue with a furnace. It correctly comes into a Y, is properly sized, and doesn't make any immediate 90 degree turns. HVAC observed great venting with via lighter test with lit and unlit.

The past year
- Plumber nor hvac couldn't identify the issue, so I've been using it at a sub-120 temp for the past year, and it's tripped once or twice a month. A couple weeks ago, the pilot stopped lighting. The thermopile couldn't get enough voltage to power the gas valve. When they looked at it, it was due to possible obstruction in the pilot gas line. Whenever I was able to get the pilot lit for a few seconds, the flame was very weak. So they replaced the gas valve again. It fixed the pilot issue, but the thermal switch issue remains.

I only figured out after this last bit having a box fan move air around near the tank (low speed) prevents the switch from tripping. HVAC said there is NO way there's a fresh air problem or a venting problem. So what about moving air prevents this? I have a 10-year warranty on the tank, but I will get charged labor to have it swapped out, looking to exhaust all my options.

Thanks for reading!

 

[Fitter30]

Thermopile puts out 300 mv to 750 mv1/3 to 3/4 of a volt dc ( most run 500 mv up) . Every connection has to be almost perfect. Have a muilti meter with a mv scale? Model # doesn't match any # found a 150T6N shows a thermocouple not a thermopile which is 35 mv. Any numbers on gas valve and brand? Take a pic of the flues from wh and furnace where they connect together. Have a old skinny birthday candle? On a piece of tin foil place candle on foil lay it down put it by the draft diverter ( open area between heater and space between where the flue starts) 1/2" from the outer flange. What I'm looking for if there is a draft problem the candle will change shape showing that there is a back draft. Service and parts manual.

Bradford White For The Pro®

 

[Sponsor]

 

[tmhinworks]

Thanks for the info!
I had a typo, it is indeed a 150T6N. This model does have a thermopile, which reads normal. I actually just had the gas valve swapped out because the pilot was weak and the thermopile wouldn't get past 210mv. They suspected debris in the gas line lowered pressure to the pilot. With a new valve, I still have the problem with the thermal switch tripping.

I had a couple different hvac companies look at the venting. They both did the smoke/flame test with all combinations of things (furnace only, furnace+wh, wh only, pilot only). In each case they said there was good upward flow out of the wh flue. The WH itself is in a 1200 sq ft basement with 2 fresh air sources (an open window and an 8" intake literally right behind the WH, so they didn't suspect inadequate combustion either.

Gas pressure was tested at the main, and at the WH valve (red handle in the pic above). The gas valve is the Icon II system.

The issue of the thermal switch tripping has been happening since the day we put it in 1 year ago, and it's undergone 2 gas valve/thermopile swaps since then.

A couple other suggestions I've heard were:
1. Flammable vapor detection (their vapor guard barrier thing) preventing flammable vapor ignition outside the combustion chamber and causing the switch to reset. So I removed all paint/litter box/etc from the room. It's still happening, so that isn't it.

2. Baffle issue in the flue - misaligned/damaged/obstructing the flue and causing gas buildup which eventually trips the thermal switch. If I jostle the WH a bit (very little push), I can hear the baffle rattle around in there. Is that normal, or does it indicate something is loose?

 

[Fitter30]

Need pic of the y connector and going into the main flue. The candle is for what might happen for extended time period. Maybe the wind picks up changes direction or the heater starves for air. Furnace has a combustion fan. What baffle in the flue? The one in the pipe going thru center of the heater. It's made to slow down the flue gas so the water has more time to pick up heat.

 

[Master Plumber Mark]

I dont like the fact they did not install a thermal expansion tank on the unit
or installed the unit on bricks in a saftey pan but that is the way it goes........

Loosen the firewall on the front of the unit and give it a 1/4 inch
gap so that more air can get into the fire chamber....

also Take out the viewing glass to allow more air into the unit.......

if neither of these things work, then you have a dog on your hands and
you just need to claim its leaking.. .(you do this by pouring a cup of water down the flu pipe)
. if its less than a year old the change out should be free of charge....

have the new unit installed on bricks and in a safety pan with a thermal expansion tank on it

 

[GReynolds929]

It should have been replaced before the labor warranty expired.

 

[Master Plumber Mark]

It should have been replaced before the labor warranty expired.

Well,,, I have never had a Rheem or Bradford white give me that much trouble and if it
would have it would have been shitcanned and replaced........

The warranty is good for 6 years so the original plumber needs to pull his thumb out of his
ass and make it right....its not gonna cost him anything but his time.....

The plumber that originally installed it should "man up" and just replace this unit as a gesture of good
will ......... Its not gonna cost him more than a morning of work but it could bring him a lot of
good karma coming his way by word of mouth....

this is just a situation where you can make things right
and you will probably get some very good google reviews from the customer
or you can "wimp out" and you probably will get some very bad reviews....

I would probably give this plumber a very bad review especially
if you had to pay other people to come out and fool with this peice of junk
after he hung you out to dry and would only do the minimum....

 

[tmhinworks]

Sorry for the delay. I scheduled a total WH swap under warranty and didn't want to waste your time with troubleshooting that wouldn't have mattered.

After the total swap, the problem went away. From right away I could tell a difference. The WH is "louder", i.e. I can hear the combustion easier than before, and if I look in there, the flame looks substantially more healthy with no orange whatsoever. To me, this confirms what I've heard with this design; something wrong with the air intake. Not dust/dirt, but something else, like insulation blocking issue or physical defect in the flammable vapor guard stuff that blocked combustible air.

 

[Master Plumber Mark]

Sorry for the delay. I scheduled a total WH swap under warranty and didn't want to waste your time with troubleshooting that wouldn't have mattered.

After the total swap, the problem went away. From right away I could tell a difference. The WH is "louder", i.e. I can hear the combustion easier than before, and if I look in there, the flame looks substantially more healthy with no orange whatsoever. To me, this confirms what I've heard with this design; something wrong with the air intake. Not dust/dirt, but something else, like insulation blocking issue or physical defect in the flammable vapor guard stuff that blocked combustible air.

I have had to take out the looking glass portal many times on any brands over the
years to get more air into the units due to the excessive amounts of lint in the rooms
This has mostly happenned with Smith water heaters....

Bradfords have never been much of an issue...

also you ought to give the company that switched it out a great 5 star review on google