f.FLAME SENSOR FAULT - if there is a problem/fault within the flame sensing circuit or the Flame Probe, the “red” L.E.D. (light emitting diode) indicator light flashes 2 blinks (i.e., FLAME SENSOR FAULT) continuously until the problem/fault is corrected (fixed) or until the HSI Module is reset manually.
2.TROUBLESHOOTING/SYSTEM DIAGNOSIS (detailed)
TROUBLESHOOTING (Service Checks)
| SYMPTOM |
| Cause |
1. | NO L.E.D. INDI CATOR LIGHT | A. | MISWIRED |
|
| B. | TRAN SFORMER BAD (24 volts) |
|
| C. | FUSE/CIRCUI T BREAK ER BAD |
|
| D. | HSI MODULE BAD |
2. | GAS VALVE ON - NO HO T SURFACE IGN ITOR | A. | DEFECTIVE HO T SURFACE IGN ITOR |
|
| B. | MISWIRED |
|
| C. | HSI MODULE BAD (check voltage at Hot Surface Ignitor) |
3. | HO T SURFACE IGN ITOR ON - NO GAS VALVE | A. | GAS VALVE COI L OPEN |
|
| B. | OPEN GAS VALVE WIRE (MV1 or GND) |
|
| C. | HSI MODULE BAD (check for voltage between MV1 and GND) |
4. | FLAME OKAY FOR T.F.I. (TRI AL FOR IG NITION) | A. | DEFECTIVE HO T SURFACE IGN ITOR |
| NO FLAME AFTER T.F.I. | B. | S2 WIRE BAD |
|
| C. | POOR GROUND (GND) AT BURN ER |
|
| D. | POOR FLAME (check flame current) |
a. System Diagnosis
1)Gas Pressure
A gas pressure test should be taken at the gas valve pressure tap provided on every gas valve to assure that the water column (W.C.) pressure is correct and consistant.
There are two (2) types of devices used to measure water column (W.C.) pressure. They are the spring/mechanical type gauge and the water column test gauge (manometer). The use of the spring/ mechanical type of gauges is NOT RECOMMENDED because they are very easily damaged and they are not always accurate. The preferred type of gauge is the manometer because it is a simple devise to use and is highly accurate. A manometer is simply a glass or trans- parent plastic tube with a scale graduated in inches. When it is filled with water and pressure is applied, the water in the tube rises, showing the exact water column (W.C.) pressure.
WARNING: Test all connections for leaks by brushing on a soapy water solution.
NEVER TEST FOR LEAKS WITH A FLAME!!!
a) Connect water column test gauge (manometer) to the gas valve tap (1/8” N.P.T.).
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