31 MAY 01 Water Heater Service.
This is one of the 2 common types of water heaters, 6 gallon,
DSI (direct spark ignition) The complaint is "sputtering during ignition". First, record the model and serial numbers, if
you ever want to ask questions over the phone, these numbers will put you and the person
on the other end, on the same page.
Start out by removing the Brain, electrodes, and the
chimney. Turn off the wall switch, and run the hot water faucet for a few minutes( this is adding cold water to the tank, do this for
5 minutes_ BE CAREFUL- THE WATER CAN BE REAL HOT) Next, turn off the water
supply to the motor home( or turn off the water pump.) Then, open the T&P Valve (this
releases pressure from the tank)
At this point, I wanted to catch the sediment in the tank to show.
This sediment is what happens to your water in 2
years (did you note the 2 previous drain
plugs?) It is what is in your water, then heated to 120 degrees and allowed to set. These
deposits also promote corrosion INSIDE your water tank.
I am using a hook type tool that blasts water against the inside of the water tank,
developing a good deal of pressure.
The option is to simply let the water run at full pressure for 1/2
hour. At any rate, flush the water tank for 30 minutes clear.
Now we look at the Chimney. All manner of debris can
accumulate. Matches, paper, small sticks or grass, carbon. These chimneys come in 2 basic varieties. The other type
is simply a big straight tube, with a flat metal divider the flame must divert past. This type
is a horseshoe shaped tube the flame travels through.
There is a long shafted brush to clean this type of chimney. After a good scrubbing, rinse
out the chimney with water until clear.
Now, we will inspect and clean the electrode assembly.
The place to keep an eye on is the bend in the burner tube. In the late Spring, Spiders will
build nests in the bend of the tube. This is an area of non-combustion, so the nest doesn't
burn, but it does disrupt the flow and mixing of the l.p. and air. I have hooked a piece of
gray scotch pad with "bailing wire" to facilitate threading the pad through and scrubbing it
out. The pad is also used to clean the electrodes. The electrodes can stand a little pitting,
but be quick to replace the assembly if the pitting is rough, or the electrode looks like a
arc welding rod. Some wear is normal, but don't be afraid to have a QUALIFIED TECH look
The next important item to pay attention to is the seal at the L.P. Gas line. On
Motor Homes this seal is real important as it prevents "Articles of Combustion" from
entering the coach. ( NOTE- It is not recommended to use the LP function of your
appliances while driving. Either depend on the outstanding insulation in the refrigerator, or
water heater, or use the generator and the Electric function of your appliances.)
Make sure to keep this seal in good shape.
Now we will examine the brain and it's plug.
Plug and Board
The strip plugs contacts are actually on the back side of the control Brain. To clean, use a
pencil eraser or (if you are a guitarist, the
calluses on your left fingers) Don't use anything
coarser! The next important point is the
ground screw. Make sure the screw is good, and
can be firmly tightened, and forms a good ground to the face of the water heater.
At this point, if anything confused you or looked out of place- Get thee to a real Tech. Past that,
you are ready to do a bit of detailing with a little sandpaper and spray paint.
You can now close the T&P Valve, turn on the water supply, and fire off your water heater.
This last adjustment I can only show you, being the adjustment of the air shutter on the
a touch" of yellow"
The flame show be relatively quiet, and show "just a touch" of yellow. If your water heater
sounds like a jet engine - that is bad. If you cannot hear the flame at all - you are not there
yet. This is a touchy adjustment and I really have to request you get a qualified service
person to perform it for you. It is as important as having a well adjusted carburetor on your
car. On a final note, if replacement of the drain plug is necessary, do so with original
equipment. Some water heaters are equipped with a nylon drain plug- do not replace this
with a metal plug, as the different metals( at the points of contact-the threads- will be
highly susceptible to corrosion. One
other type of water heater- most generally, there is
a replaceable anode. It costs about $13.
This Water Heater Service generally takes 50- 60 minutes( includes a little elbow grease
and spray paint ) For a 1 hour charge , to
receive a thorough service, and a excellent
explanation of the operation of a dsi water heater, this is something that should happen
every other year( at least). Keep a cheap water filter on your supply hose, and a extra
cartridge under your kitchen sink.
Drop me a note, and let me help you get the most from your RVing Experience.