Rheem 40 gallon gas hot water heater, pilot light
To make a short story long (I need to include all details, sry)…
I got up one morning and realized that we did not have hot water. I
re-lit the pilot light and as soon as the burner went out from heating
the water up, the pilot light would go out. After reading several posts
regarding this issue, it seemed apparent that the thermo-coupler was
the problem. Since I am a little bit handy around the house and very
tight when it comes to opening my wallet, I bought the device from
Lowe’s ($8.98) that was recommended by my online advisors and after a
few googles, figured out how to change it. No help. The pilot light
still goes out.
I gave up and went to Home Depot to purchase and schedule the installation of a new hot water heater.
A new Direct Vent type water heater costs around $800 with an
additional $450 for “special” installation. Add a few fees to that and
the grand total came to about $1450.
I felt like I had no choice since my wife and 2 daughters refused
to live their life without hot water and I had no clue about how to fix
the dam thing.
The plumber assigned to the installation stopped by to evaluate the
site conditions and quickly noted to me that the 8 year old water
heater tank was in good condition and that the gas controller was
probably faulty, which could be purchased online from the manufacturer.
I quickly cancelled the Home Depot order and purchased the controller
for about $120 after shipping and tax. Immediately after the
installation it seemed that the problem had been solved. A few days
later the pilot light went out.
I called the plumber and explained the situation and he recommended
that I purchase another controller because the one that was shipped to
me was probably bad. I searched around town and found a plumbing supply
company that had the correct model in stock. Two days later the pilot
light was out. I cleaned up the controller and returned it to the store
and asked the plumber to please schedule a visit to repair this dam
When the plumber arrived, he hooked up a gauge in several locations
and confirmed that the correct amount of gas (cfm) was being delivered
to the controller, pilot light and burner. He then proceeded to remove
the fire box to make sure that the igniter, thermo-coupler and pilot
tip were set properly. He inspected the pilot light tip and said that
he found the problem. Using about a 1/64” tip drill (can be purchased
at a welding supply store), he cleaned the tiny hole that releases gas
to the pilot light. I felt a sigh of relief because I was certain that
the problem had been solved. $65 dollars (plumber’s fee for an hour of
work) and 4 days later the pilot light went out.
I called the plumber and he said that the controller that I
purchased online must be bad. Too embarrassed to return to the first
plumbing supply store, I found another one in a different town that had
the correct model in stock. Three days after changing the controller
the pilot light went out. I returned the controller and a six pack
later I decided to do some extensive googling.
The key term here is “DIRECT VENT”. This seems to be a very common
problem with direct vent water heaters and I was about to find out the
reason for this phenomenon. I read a post by an individual who wrote
that if the vent becomes detached that the inflow of air can become
contaminated and extinguish the pilot light. I decided that before I
spent any more money on a plumber that I was going to take the vent
apart and find out what makes it tick.
My direct vent system has 2 parts to the venting, an inner pipe (3”
nominal diameter) that serves as the exhaust and the outer pipe (5”
nominal diameter) that serves as the internal flow of air which
supplies the pilot light and burner with oxygen. On the outside of the
house a vent hood helps to segregate the two by extending the exhaust
about 3” beyond the intake. I looked into the hood at the end of the
pipes and discovered that the internal pipe which consisted of a 2
piece slip joint had come loose from the elbow that sets on top of the
water heater. This slip joint pipe was not attached at any point with
screws or clamps and was loosely setting over the elbow on one end and
into the hood on the other end, allowing it to detach. Apparently, when
atmospheric conditions were right, the burner idled down from heating
up the water and extinguished the pilot light because the intake was
saturated with CO2 from the connection failure.
I purchased a section of 3” pipe that was long enough to be
installed in one piece. I connected it to the elbow using a stainless
steel hose clamp. I had to disassemble the pipe 3 times to make
adjustments to the length and position before I got it right, but I
should not have any more problems with the pilot light.
The problem here is time. It takes a lot of time to get this right.
When the plumbing contractors installed this unit during the
construction of the house, there was no one around to make sure that
they got it right. It is probably common to use a 2 piece slip joint
type connection, but I feel like it should be attached with screws or
clamps. In my opinion it is not rigid enough and can detach easily,
especially if it is not installed properly. A one piece connection that
is attached at one end with a hose clamp and then held in place at the
other end by the hood is fool proof.