Part 3 - Munchkin HIGH EFFICIENCY HEATER with the "925" Controller Operating Instructions Manual

It is recommended that a soapy solution be used to detect leaks. Bubbles will appear on the pipe to
indicate a leak is present. The gas piping must be sized for the proper flow and length of pipe, to avoid
pressure drop. Both the gas meter and the gas regulator must be properly sized for the total gas load.
If you experience a pressure drop greater than 1" WC, the meter, regulator or gas line is undersized or
in need of service. You can attach a manometer to the incoming gas drip leg, by removing the cap and
installing the manometer. The gas pressure must remain between 3.5" and 14" during stand-by (static)
mode and while in operating (dynamic) mode. If an in-line regulator is used, it must be a minimum
of 10 feet from the Munchkin. It is very important that the gas line is properly purged by the gas
supplier or utility. Failure to properly purge the lines or improper line sizing, will result in ignition
failure. This problem is especially noticeable in NEW LP installations and also in empty tank situations.
This can also occur when a utility company shuts off service to an area to provide maintenance to their
lines. This gas valve must not be replaced with a conventional gas valve under any circumstances. As
an additional safety feature, this gas valve has a flanged connection to the Venturi and blower.
DUNGS GAS VALVE
Fig. 3-1
Failure to follow all precautions could result in fire, explosion or death!
THROTTLE ADJUSTER
(NOTE: IF FOR ANY
REASON THE THROTTLE
NEEDS TO BE
,
ADJUSTED IT IS
VERY IMPORTANT THAT
A "COMBUSTION
ANAYLYZER" BE USED
TO ENSURE SAFE AND
PROPER OPERATION.
TURN THE ADJUSTER
TO THE (+) TO
INCREASE GAS OR THE
(-) TO DECREASE THE
GAS SUPPLY. THIS
ADJUSTMENT COULD
AFFECT CO/CO%
LEVELS. MAKE SURE
THE LEVELS
CORRESPOND TO THE
CHART IN COMBUSTION
SETTINGS. )
WARNING
GAS CONNECTION
13