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CAUTION: If control has been exposed to water in any
way, it must be replaced. If gas valve fails to shut off, do
not turn off electrical power. Turn off gas supply allowing
fan or circulating pump (if so equipped) to continue run-
ning until system has cooled. Replace control.
Millivolt System
The millivolt system and individual components may be
checked with a millivolt meter having a 0-1000 MV range.
Before checking system, be certain wall thermostat lead
wire does not exceed length recommended in Wiring
Section Table, and all connections are clean and tight.
Conduct each check shown in chart below by connecting
meter test leads to terminals as indicated. All readings
are closed circuit.
A. TEST RESULTS
If the reading is more than 100 millivolts and the automat-
ic valve does not come on, replace the valve operator. If
the closed circuit reading is less than 100 millivolts, deter-
mine the cause by proceeding with steps "B" and "C".
B. TEST RESULTS
If "B" reading is less 325 MV, clean and tighten all electri-
cal connections and adjust pilot if necessary to increase
millivolt output. If unable to adjust to least the specified
minimum, change the thermopile. When proper thermo-
pile output is obtained, the magnet may then be checked.
With pilot operation, allow meter reading at dropout point
of magnet. If magnet remains locked up to a reading of
120 MV or less, the magnet is good.
C. TEST RESULTS
If "C" reading is more than that specified for that specified
for the system being checked, clean and tighten thermo-
stat leads and connections, shorten leads wires if possi-
ble or use heavier gauge wire. Rapidly cycle thermostat
to clean contacts, or change the thermostat.
PROCEDURE FOR LIGHTING
OR RELIGHTING
Dials must be operated by hand. DO NOT use pliers,
wrenches or other tools to turn dials.
The Gas Cock Dial has a dual function:
A) Complete control of gas to pilot and main burner.
B) When in pilot position, it is the reset mechanism for
the automatic pilot.
The Gas Cock Dial cannot be turned to “OFF” position
without first depressing dial in “PILOT” position and then
rotating to “OFF”.
1. Depress and turn Gas Cock Dial to “OFF” position.
2. Turn temperature dial (hydraulic models) or wall
thermostat (24V and millivolt models) to “OFF”
or lowest setting.
3. Wait at least 5 minutes (10 minutes for L.P. gas)
to allow gas which may have accumulated in burner
compartment to escape.
4. Turn Gas Cock Dial to the “PILOT” position.
5. Hold match at pilot burner. CAUTION: If pilot lights
without depressing Gas Cock Dial replace
control. Depress and hold Gas Cock Dial while
lighting pilot burner. Allow pilot to burn approximately
one half minute. (1-1/2 minutes for millivolt models)
before releasing Gas Cock Dial. If pilot does not
remain lighted, repeat operation allowing longer
period before releasing Gas Cock Dial. (Adjust pilot,
if necessary, as noted under “Pilot Burner
Adjustment.”) The thermo- couple or thermopile
may also be defective and should be checked out.
(See SERVICE INSTRUCTIONS.)
LEAK TEST
Test for gas leaks after valve installation with main burn-
er on. Use a rich soapy water, and paint all piping and
tubing joints liberally. Bubbles are indicative of a leak.
SERVICE INSTRUCTIONS
