Laars 9600 HWG, Инструкции по установке, эксплуатации и обслуживанию

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LAARS Heating Systems
NORMAL SEQUENCE
FAILURE TO COMPLETE EVENT CYCLE
EVENT
CONTROL FUNCTION
VERIFIED
LIGHT CONFIRMS EVENT
NO LIGHT OR
BLINKING LIGHT
ACTION FOR DIAGNOSIS
A. Power switch on.
Integrated boiler control (S9301A).
Green "POWER" light on. Note: If internal pump is running unit may be in lockout. Reset power switch.
1. No. 120 VAC supply.
1. Read voltage betwen black & white wires at back of (120 VAC) plug.
2. Defective 24 VAC transformer (Check 3 AMP inline fuse).
2. Read voltage between yellow wires at back of (VAC 24XFMR) plug.
3. Defective S9301A module.
3 Replace S9301A module part #2400-224.
B. Pre-purge low limit aquastat or thermostat calling (2-17 secs).
1. Internal pump starts.
Red "PURGE" light on NOTE: If unit is in purge mode without light, stack switch is not proving air flow.
1. Internal pump defective or air bound.
1. Check for 120 VAC at module pins marked "CIRCULATOR" (opposite brown & white).
2. Low limit (HW-only), operating control, safety limit, system or differential pressure switch, stack switch.
2. Defective low limit, operating control, safety limit, or system differential pressure switch.
2. Jump control wires, one control at a time to identify open circuit in control (no continuity) FOR DIAGNOSIS ONLY.
3. Blower starts.
3. Defective inducer (blower).
3. Check for 120 VAC at module pins marked "INDUCER" (opposite gray and white wires).
C. Ignitor heats up and remains on (17-39 secs).
Ignitor via S9301A.
Red "IGNITOR" light on. Red "PURGE" light off. Blower continues to run.
Ignitor does not heat up - look for heat up at ignitor base.
Check for 120 VAC at pins marked IGNR (blue wires) during "IGNITOR" light "ON".
D. Gas valve energized (37-43 secs).
Gas valve opens.
Red "VALVE/FLAME" light on.
1. Stack switch does not confirm air flow. 2. Gas valve has short.
Check for 24 VAC between orange and yellow wires on gas valve when red "VALVE/FLAME" light is on.
E. Ignitor off (39 sec) Gas valve energized (39 - 43+ sec).
Ignitor, air & gas source.
Ignitor monitors flame via flame rectification to ground (0.6 - 1.0 microamps).
Unit transfers to purge 12-15 seconds after valve/flame light on and repeats sequence.
See trouble shooting section under "cross contamination" and "short cycling" in service manual.
Quick Reference
T
rouble Shooter
S9301A Control Module