Dungs Gas Valve - Heat Transfer MODCON VWH 300 LP Installation & Maintenance

PART 7: GAS PIPING
tor is used, it must be a minimum of 10 feet from
the Mod Con. 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 fail-
ure. This problem is especially noticeable in
E. DUNGS GAS VALVE
GAS OUTLET
GAS OUTLET
PRESSURE TAP
GAS VALVE
GAS INLET
PRESSURE TAP
GAS SHUT-OFF
VALVE
Fig. 7-2
41
GAS-FIRED HOT WATER SUPPLY BOILER
(CONTINUED)
MOD CON 300 GAS VALVE
A
OFFSET ADJUSMENT
CAUTION: DO NOT REMOVE THIS SCREW
OR ATTEMPT TO MAKE ANY ADJUSTMENT TO
THIS SCREW WITHOUT A COMBUSTION
ANALYZER
GAS INLET
NEW LP installations and also in empty tank sit-
uations. This can also occur when a utility com-
pany 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.
THROTTLE ADJUSTER
NOTE: IF FOR ANY REASON THE THROTTLE
NEEDS TO BE ADJUSTED, IT IS VERY IMPORTANT
THAT A "COMBUSTION ANALYZER" BE USED TO
ENSURE SAFE AND PROPER OPERATION.
TURN THE ADJUSTER TO THE (+) TO INCREASE
THE GAS OR (-) TO DECREASE THE GAS SUPPLY.
THIS ADJUSTMENT COULD AFFECT CO/CO%
LEVELS. MAKE SURE THE LEVELS CORRESPOND
TO THE CHART IN COMBUSTION SETTINGS.
(FIG. 10-1)
DETAIL A
SCALE 2 : 3
Boiler Manual
LP-205-AA Rev. 6/3/08