Groen HY-12GF(CE), Operator Manual & Service Manual

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OM/SM-HY-12GF(CE) & HY-24GF(CE) 35
OM/SM-HY-12GF(CE) & HY-24GF(CE)
3.4.3 Problem: Steamer Cavity Turns Off During Operation — Continued
PROBABLE CAUSES CORRECTIVE ACTION
Defective high limit steam generator thermostat Check for defective steam generator high limit thermostat. It should
be closed and will open only when temperature exceeds 113ºC.
Check thermostat continuity with meter. If thermostat is OPEN,
steam generator is less than 113ºC., replace the thermostat.
Fuses blown Check fuses F2 and F3 and replace as required
Water level probe shorted Measure AC volts from probe to ground. An open probe will read 9-
13 VAC. A shorted probe (sensing water) will read 0.1-8 VAC.
If shorted clean the probe.
Transformer TR1 could be defective Turn on unit power and check supply voltage. Then check for 24
VAC at transformer TR1 secondary terminals with wires
disconnected. If 24 VAC is not present, replace TR1.
WARNING
DO NOT ATTEMPT TO LIGHT THE PILOT BURNER WITH A
FLAME .
Pilot burner flame goes out Check for proper pilot flame height. Check for defective main gas
valve. Check for air flow that
blows out pilot.
Gas supply turned off or interrupted Close gas supply line and check for cause of gas supply loss. Have
problem corrected.
Air in gas supply line or blockage Check supply line. Clear or clean as required.
WARNING
DO NOT ATTEMPT TO LIGHT THE PILOT BURNER WITH A
FLAME .
Pilot burner not ignited. Perform the following "trial ignition," and look and listen for spark:
Attempt to ignite the pilot burner. If this burner does not ignite within
90 seconds after the pilot switch is turned on, turn off the pilot
switch. Wait at least five minutes before attempting to reactivate the
pilot switch. Repeat the trial for ignition. The pilot may require
several trials for ignition to bleed air from the gas piping. After the
initial attempt, subsequent startups should require only about two to
five seconds to achieve pilot ignition
Spark observed.
Turn on oven power. Refer to schematic diagram and check for
24VAC at igniter module terminals MV-PV and PV.
3.4.4 Problem: Steamer Cavity Does Not Achieve “Ready” Status
Low power supply - Iower than 10 percent Check voltage. Have customer call power company.
Steam generator overfills See Problem 3.1.5