Often when we test gas piping, we cap off the valves because they do leak. When the test is complete, we reconnect everything.The gas company didn't red flag the leak.
I just installed a new Rheem Powervent water heater (natural gas). My wife said she smelled natural gas in the basement a week later so I checked all of the lines with soap and water and didn't find anything. So I called the gas company and they came out and said that they found a ".05" leak at the water heater's gas valve (it says Honeywell on it). I then called Rheem and they said it was normal to have a leak there. I think they're just avoiding action because the gas company didn't red flag the leak.
2 questions: Is a leak of this sort "normal"? What does a ".05" leak mean for my family's health?
So it sounds like a small leak is ok. I just wanted someone other than Rheem to verify that. Thanks!
OK with who? I would never accept a gas valve that leaked a nose-detectable amount of gas, unless perhaps you
have insanely sensitive olfactory powers. That would sort of defeat the whole point of putting those odorants
into the gas. Control valves and such are disconnected during leak testing because
they are not usually rated to withstand the pressures used to test the piping. I've had a few successes with leaking
control valves by just tightening the body screws, thus stopping the tiny leak at some gasket or other.
The Rheem technical support person said that without a hole (supposedly where the leak is coming from) there would be a vaporlock situation when the water heater turns on. That doesn't sound right to me, either. I'm used to water heaters with a pilot light, so I'm still confused about this. My water heater is still very much under warranty and they logged my call from yesterday. I might call them back and see if I can get a replacement valve. Why didn't the gas company care that there was a leak? They basically just said that if it doesn't cost me any money to get a new valve (which it won't) then I may as well.
I have a Rheem Power Vent and it can report absolutely zero gas leak! You might try tightening any screws, but that's the extent of what I would do.
I always thought "vaporlock" referred to a situation where a portion of some LIQUID fuel boils into the vapor (gaseous) state,
thus thus interfering with the normal flow of the liquid. Can't imagine what that would have to do with a gas appliance.
I think it would be normal to briefly smell gas when the appliance fires up, and also normal for a small amount of residual
gas to be present after applicance shutdown. Electronic gas sniffers can detect gas in amounts that are in no way dangerous,
and could even be said to be normal. Here's a PDF document from Honeywell giving their viewpoint on the matter: http://hphaa.com/knowledge/FAQs/gas-valve-leakage.pdf
On the other hand, if you're getting whiffs of gas every time you walk by the water heater, traceable to the gas control valve, that would
indicate to me a defective valve. It all boils down to the question: "How small is small?".
RESPONDING TO GAS LEAKAGE
To respond effectively to gas leakage complaints,
service technicians need to take a two-step approach
before identifying the gas valve as the problem:
First, they must identify the presence of gas by
using a reliable gas detector. And second, they must
verify that the flow of gas coming from the valve is
unacceptable by using a reliable flow meter.
If gas is present in low concentrations as the
result of furnace design and the trace leakage
phenomenon, replacing a gas valve will not solve the
problem. They must educate the appliance owner
about the source of the gas odor and assure them that
it is both safe and normal for that appliance.
Last edited by Terry; 11-14-2012 at 08:45 PM.
I wouldn't say I smell gas walking by the unit, but if my nose is within 4 inches of the top of the valve the gas smell is very evident. And it's not like I only smell it right after the unit turns off: If that was the case I could see how maybe some residual gas in the line (between the valve and the burner) could cause the smell. This seems to clearly be a "leak" and I'm struggling with the notion that it's by design. Kreemowheet hit the nail on the head with "how small is small". I think I'll have the gas company company come out one more time when I'm there and get the final word on how much the thing is actually leaking.
FWIW, have you tried to tighten any assembly screws on the valve? Not sure if there are any without taking labels off (and probably messing with any warranty), but if there are, I'd do that and see. Have you tried the old soapy water test to isolate where it's leaking? It may only take a small tweak to tighten down the fitting, or gasket and eliminate the leak.
Important note - I'm not a pro
Retired Defense Industry Engineer
Page 26 of this document shows my gas control unit: http://waterheatertimer.org/pdf/Hone...rror-codes.pdf
I don't really see any external places to tighten anything up.
I've emailed Honeywell directly. I'll see what their opinion is.