I found the problem. There are two gas tubes coming out of the temperature
control box, a big one supplies the burner, and a small one supplies the
The installer did not use any joint compound on these tube fittings, so they
leak a little. Instead, he overtightened the large nut, but that still
I bought some joint compound from HD (says ok to use on gas pipe) and put
them in the threads. That's the white stuff you see in the threads. This
eliminates almost all the gas odor. I no longer smell gas when standing next
to the water heater. I still smell a faint odor at the bottom of the control
I think a little bit of gas is leaking out between the nut and the tubes.
How do you seal this? Yes, I know I can call the gas company, or call the
installer to fix it. That would be the last resort. I want to learn
something in the process if I could.
Then you need to replace the fittings--joint compound is for _threaded_
pipe fittings where the threads make the seal, _not_ for tubing
fittings. In a tubing fitting (or a pipe union, as well) the seal is
the mating between the taper and the sleeve _not_ the threads at all.
Sounds like they tried to reuse an old fitting that has either corroded
enough to no longer have a precise matching or, in trying to make that
connection, overtightned and likely crushed the ferule.
The real solution is to replace the fittings if you have sufficient
length to get a fresh tubing end or the tubing and fittings if not.
I installed a new gas waterheater and for weeks later kept getting a
faint smell of gas odor. Rechecked my connections and they were tight.
Finally checked the internal connections and found a loose one - came
that way from the factory. Tightened it and never smelled gas again.
Your question is pretty dangerous, remember that this is a public forum and
therefore we can't tell what your situation and what your intelligence level
really is, so a question involving highly flammable gas typically is
answered very conservatively.
As to whether it is normal or not, it can yes. I have spoken with people
who do home calls and people who do training for PSE (Puget Sound Energy)
and on certain gas water heaters it is normal to smell gas around the burner
control knob. But your circle doesn't indicate that location so in my mind
you should perhaps ask your gas supplier if they can verify the installation
for you. It's what I did when I smelled gas in and around my gas control
box. No reason to risk sending your water heater into low orbit.
OK - what you are smelling is the odorant Ethyl Mercaptan which is
added to natural gas to make it detectable. Somehow the mercaptan is
being released into the air - with or without the gas. My suspicion is
some has "settled out" of the gas at the pilot. Only a fraction of a
small drop will be detectable by a sensitive schnozz.
On 11/11/2014 8:24 PM, firstname.lastname@example.org wrote:
I've had gas co out numerous times as the mercaptan smell is noticeable.
To date they've never been able to set off their high-priced,
presumable sensitive(???) detectors at any location.
I've become convinced by characteristics it's a remnant of the odorant
having been left after repair/replacement when piping has been open.
It's noticeably stronger in the well house if get a little water on the
floor near where the heater sits which I replaced the old "wild" pilot
valve on a couple of years ago with one of them newfangled, gee-whiz
thermocouple-countrolled doo-jobbie ones a couple of years ago.
I've not gotten one of the n-gas wall monitors thinking the likelihood
of them being sensitive enough to help if the gas company can't find it
with a portable going around all the piping and end devices was likely
It is disconcerting on occasion, however, 'cuz one wonders for absolute
certain whether it's just getting missed or what...
Odorant can fool you.
I worked at a place out in the country that had a small motel for new emplo
yees until they found a place. There were maybe a dozen rooms. The place
smelled so strong of gas I wouldn't have walked near it. Their claim was t
hat it was normal. The odorant addition machine only came in one size, and
so they had a large unit for that tiny motel. With that much odorant bein
g added it was bound to smell.
In hindsight, they were probably lying, but we all did survive. And move o
This is a farm residence/homestead; the pot is at the tap off the
pipeline at the meter location some quarter-mile from the house...which
brings up other stories that initially was un-metered tap for farm/house
use as part of the right-of-way easement grandfather negotiated in the
30's when they built the line. Some 30 yr ago now, the original
pipeline company was acquired by another and they somehow found an
escape hatch that state corporation commission backed them up on to
break all those existing agreements. I've been extremely surprised they
haven't come around trying to pull the tap entirely in order to get rid
of the hassle of these scattered residential taps all over the county...
Some campers and RV have a LP detector near the
floor. But NG detector in a home? Not heard of
When I did HVAC, I used to have a gas beeper for
use on the job, but that's not the typical HO
Christopher A. Young
Learn about Jesus
Given that propane is heavier than air, having a *small* propane leak in a house with a basement or below grade crawl space is an explosion waiting to happen.
A *small* propane leak is probably less dangerous in an above grade slab house.
Given that natural gas is lighter than air, a *small* natural gas leak seems far less dangerous.
No "safe amount" of any explosive gas can be detected
by human nose. Our noses have not been trained to
discriminate between safe and unsafe odours. This is
why gas companies ask people to notify them if they
ever smell gas.
Natural gas has no detectable odor at all -- it's only the mercaptan
oderant added that can be detected by the nose. It's so strong simply
so that a tiny amount is detectable by almost everybody (albeit I can
often not notice the trace amounts spoken of above when some others
claim it smells strongly of it to them; my sniffer ain't so hot as some
The measurement devices used by the gas co aren't "smelling", they're
using active sensing to detect the actual methane/propane/whatever...
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