- The FIRST STEP in diagnosing any heater problem should
be checking the output of the air pump. Determine the air pressure required for the heater
model that is being tuned. The air pump, in turn, is responsible for
- If you do not know the required pressure look for a
decal on the side (usually) of your heater. This decal will state the
model number, serial number, fuel capacity, pump pressure, etc.
- If your plastic end cover looks like this......
M29609 has 2
threaded holes. The hole on the left has a square plug inserted. Remove the
plug. Screw in the nipple end of the gauge into the threaded hole. Check for
air leaks with soapy water.
If your plastic end cover looks like this......
2 threaded holes. The shorter projection with a hole on the left has a square plug inserted. Remove
the plug. Screw in the nipple end of the gauge into the threaded hole. Check
for air leaks with soapy water.
4. The other hole (longer projection) has a screw with a hole which adjusts a
ball and spring relief valve assembly. Carefully adjust the screw until the
gauge is reading the pressure level that is specified on the heater's label.
If operating properly, the pump should produce more pressure than is
required to operate the heater. The relief valve allows the excess air to
escape before being sent to the nozzle.
5. Replace plug. Test for leak.
6. If you are unable to reach the desired pressure spray
soapy water around the seal of the end cover- at the same time check the
plastic cover for a crack. A cracked end cover will not allow the heater to
perform properly and will not allow for an accurate reading. The pump must
be set at the specified pressure in order to have adequate fuel delivery an
adequate fuel atomization. Replace if needed.
7. If you set the pressure to specs and the heater does
not perform properly or the cone does not glow a soft red, then check for
other fuel delivery problems such as a clogged fuel filter, cracked rubber
hose, clogged or worn nozzle, or a cracked nozzle adapter. Soapy water lightly sprayed in these
areas will quickly identify the problem most of the time. Any air leak
will create problems.