VHX SERIES STEAMER - SERVICE PROCEDURES AND ADJUSTMENTS
C.Verify LED’s on the water level control board, HL LED should be off, and LLCO LED should be illuminated.
3.Open the ball valve in the probe housing assembly (boiler left side) about half way, to gradually remove boiler water and activate a fill cycle. Do not press the reset switch to start the ignition cycle. The next step requires a visual sight glass measurement that cannot be obtained, if there is boiling action in the vessel.
A.Verify water level in the boiler sight glass drops 1/4" to 3/8" before a fill cycle is initiated. Repeat at least twice to verify correct fill.
1)If proper fill wasn’t obtained:
a.Verify probes 50, 51, and 52 have the correct colored wire to them and to the water level control board.
b.Remove the 3 probe assembly, clean lime scale
c.Remove 3/8” flex line from the probe housing assembly to the boiler and remove any obstructions. The 1/4" compression fitting elbow and 1/4" tee into the boiler shell for the balance tube are sloped 1/8" so condensation drains into boiler. When replacing, the assembly must have this slope to prevent a blockage from condensate
4.Test the water level control board LLCO circuit.
A.With the boiler full with water, turn off the water supply and open the ball valve in the probe housing assembly.
B.Shortly after the water drops below the lowest visible level in the sight glass, the LLCO LED on the water level control board should turn off, LLCO relay should
C.Repeat at least twice to verify correct LLCO operation.
Auxiliary Low level Cut-Off Control
5.Continued testing with focus on the auxiliary LLCO circuit. With water below the lowest visible level in the sight glass (below Aux LLCO probe), and boiler in state of initial fill:
A.Verify Aux LLCO LED is off on the Aux water level control board.
B.Verify Low Water light is illuminated (front control panel).
C.Verify 24 volt AC is on Aux LLCO COM, and 0 volt is on Aux LLCO N.O. contacts.
1)With the water level above the Aux LLCO probe and in the initial fill state:
a.Verify Aux LLCO LED is illuminated on the auxiliary low water board.
b.Verify N2 on the relay board is illuminated (new style boiler controls only).
c.Verify the "green" ready light in the reset switch is illuminated.
d.Verify 24 volt AC is on the Aux LLCO common and normally open contacts of the auxiliary water level control board.
2)With the main gas valve turned off, water supply valve turned off, and probe housing assembly ball valve opened, press the reset switch.
a.Verify low water light (front control panel).
b.Blower comes on.
c.Gas pilot cycles at approximately 15 seconds on and 5 seconds off.
3)Shortly after water level drops below the lowest visible level in the sight glass, the Aux LLCO circuit should be activated.
a.Low water light turns on.
b.Aux LLCO led turns off.
c.Combustion blower is de- energized.
d.Gas pilot stops cycling.
4)Press reset switch to verify lockout.
5)Disconnect lead wire from Aux LLCO probe. If there is any measurable resistance between the probe and the
F24700 (October 2001) |
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