VL SERIES STEAMER - SERVICE PROCEDURES AND ADJUSTMENTS
WATER LEVEL CONTROL(S)
TEST
Loose electrical connections may prevent the heat from coming on or may cause the boiler to overfill. An accumulation of lime scale on or near the water level sensing probes may cause them to retain water (moist) on the probe surface and give a false reading. Also, a cracked or damaged insulator may give a false reading. These conditions may prevent the boiler from filling or cause dry firing. Dry firing will result in damage to the heating elements on electric models or to the boiler on gas or electric models.
WARNING: THE FOLLOWING STEPS REQUIRE POWER TO BE APPLIED TO THE UNIT DURING THE TEST. USE EXTREME CAUTION AT ALL TIMES.
Solid State - Low level
1.Turn the power switch ON.
2.Ensure that water is filling the boiler.
A.Confirm that water supply valve(s) are turned on.
B.Observe boiler water level in the water level gauge. If empty, boiler should fill in approximately 11 minutes.
3.Check the voltage across terminals L1 & L2 on the board. Meter should read 120VAC.
A.If voltage is correct then the high level (HL) relay should energize, closing
B.If boiler fill solenoid is receiving power but no water is flowing, inspect fill solenoid for malfunction or valve for clogged ports. If solenoid is bad or ports can not be cleaned, then replace boiler fill solenoid and check for proper operation.
C.If boiler fill solenoid is not receiving power and the electrical connections have been checked, then the HL relay is not being energized or the
4.If boiler is filling properly, when the water level reaches the low level
5.Once the water level reaches the high level (HL) probe, the inverse latching relay of the board (solid state) should energize and lock through the low level probe (LL) and
6.If water is in the boiler but is not being detected by the water level probes, the probes may need cleaned and/or boiler delimed. See “Water Level Probes” as outlined below for inspecting and cleaning of probes and “BOILER” for a procedure on boiler inspection,
7.Turn the power switch OFF and disconnect the lead wire from each probe. Check the probes as outlined below.
A.With an ohmmeter, check between the probe terminal and boiler shell. An open circuit should be present when the boiler is empty. If resistance is present, remove and inspect the probes as outlined below under “Water Level Probes”. When the boiler is full of water, a resistance reading should be measurable between the probes and boiler.
NOTE: The actual resistance reading will depend on water quality and probe condition.
8.After performing steps
Electro Mechanical - Low level
WARNING: THE FOLLOWING STEPS REQUIRE POWER TO BE APPLIED TO THE UNIT DURING THE TEST. USE EXTREME CAUTION AT ALL TIMES.
1.Ensure that water is filling the boiler.
A.Confirm that water supply valve(s) are turned on.
B.Observe boiler water level in the water level gauge.
C.Verify boiler fill solenoid valve is receiving 120VAC and water is flowing through it.
2.Check for correct voltage being applied to the low level and differential water level controls.
A.Turn the water supply valve off then turn the power switch ON. Check the input voltage across terminals 1 & 2. Meter should read 120VAC. If voltage is correct proceed to step 2B. If voltage is incorrect, find the source of the problem and repeat this step.
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