Inspecting And Verifying Conditions - Mi-T-M Corporation HGM Serie Mode D'emploi

maKing a manometer
measuring water column
adJusting gas regulator
4

inspecting and Verifying conditions:

. Check to ensure the building is not weakened by the installation of this
unit and make sure the piping is secure.
2. Check gas pressure and check all gas piping for leaks.
a. Ensure all gas connections are made and close the valve before the
gas valve on the machine.
b. Immediately after opening the main valve, coat all piping and connections
with soapy water to check for gas leaks. Defective piping and fittings
should be replaced immediately.
c. After the meter and all piping have been checked for leaks, purge the
air from the system by removing the test tapping plug and bleeding the
line into a well-ventilated area to protect against potential fire hazard.
d. If a commercial manometer is not available, make one by using a clear
tube about /2 full of water and shape it like a U. With the main shut-off
valve closed, connect a hose barb fitting into the test tapping, connect
the hose and mark the water level as shown.
e. Turn on the main gas valve and check the water column level by mea-
suring the distance the two water levels rose and dropped from starting
level. This must not exceed 4" W.C. Start the unit and check pressure
with burner running. The gas pressure at this point should be 3-7" W.C.
for N.G. and 8-2" W.C. for L.P.-Gas.
f. Turn off the main shut-off valve, remove test fitting and replace plug.
g. Using a 3/6" hex key wrench, remove plug from test port on gas valve
inside the heater module and connect your manometer or test tube.
h. Turn on manual shut-off valve and gas regulating valve. Operate the
unit so the burner runs and check the manifold pressure. The gas pres-
sure at this point should be 2"-4" W.C. for N.G. and 8.5"-9.5" W.C. for
L.P.-Gas.
i. Shut off the unit and manual shut-off valve, remove manometer or test
tube and replace plug.
3. Adjusting the gas regulator on the gas valve normally IS NOT necessary
since it is preset at the factory; however, if it is necessary, follow these
instructions:
a. Using a 3/6" hex key wrench, remove plug from test port on gas valve
inside the heater module and connect your manometer or test tube.
b. While running the burner, use the screwdriver to adjust the gas pressure
(clockwise to increase and counterclockwise to decrease).
c. When finished, shut off the unit and manual shut-off valve, replace the
adjustment cap, remove manometer or test tube and replace plug.
installation
HGM-SERIES Hot Water Heater module Operator's Manual