TROUBLESHOOTING GUIDE
Series 44 Room Temperature Control |
| Reproduced with permission from Maxitrol® Company | |||||
Symptom |
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| Possible Cause |
| Field Test |
| Remedy |
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A. No Gas Flow. |
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| 1. | Arrow on side of valve | 1. | Install properly. |
1. | Valve improperly | ||||||
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| installed. |
| should point in direction |
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| of gas flow. |
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B. Continuous Low |
| 1. | Open circuit in | 1. | Remove wires connected | 1. | If proper resistance values |
Fire (Electronics |
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| modulator coil. |
| to amplifier terminals 6 &7 |
| are not observed, replace |
OK). |
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| and measure resistance. |
| modulator head or repair |
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| MR212 |
| wiring. |
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| 2. | Plunger missing, jammed | 2. | Inspect. Plunger should be | 2. | Clean or replace plunger is |
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| or improperly installed. |
| installed to operate freely in |
| necessary. |
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| solenoid sleeve. |
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| 3. | Ruptured main or | 3. | Disassemble valve for | 3. | Replace diaphragm if |
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| balancing diaphragm. |
| inspection of internal parts. |
| ruptured. |
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C. Continuous Low |
| 1. | No voltage to the | 1. | Check for 24V AC at | 1. | Provide 24V AC to amplifier. |
Fire (Electronics |
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| amplifier. |
| amplifier terminals 8 & 9. |
| Refer to item K1. |
Problem). |
| 2. | Short in modulator coil | 2. | Measure resistance per | 2. | If proper resistance values are |
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| circuit. |
| item 2. |
| not observed, replace the mod- |
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| ulator head or repair wiring. |
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| 3. | Short in TS144 circuit. | 3. | Remove wires connected to | 3. If readings are incorrect, replace | |
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| amplifier terminals 1, 2 & 3. |
| the TS144 or repair wiring. |
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| Measure resistance across |
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| wires 1 & 3. Meter should |
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| read greater than 2500 ohms. |
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| 4. | Faulty amplifier. | 4. | Follow procedures outlined | 4. | If power source and |
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| in “Preliminary Circuit |
| modulator coil check out |
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| Analysis” in Section IX. |
| (items 5 & 6) but proper |
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| modulating voltages cannot |
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| be obtained, then amplifier |
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| may be assumed at fault. |
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| Install replacement amplifier. |
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D. Incorrect Low Fire. |
| 1. | Incorrect | 1. | See Valve Adjustments - | 1. | Adjust to proper low fire. |
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| valve adjustment. |
| Section IX. | 2. | If greater than 1.5” |
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| 2. | Excessive negative | 2. | Close main gas supply and |
| negative pressure, check |
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| burner pressure. |
| measure manifold pressure |
| equipment for clogged |
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| with blower operating. |
| filters and other inlet air |
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| Should be less than 1.5” |
| restrictions. For other |
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| W.C. negative pressure. |
| solutions, consult factory. |
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E. Continuous |
| 1. | Faulty amplifier. | 1. | Follow procedures outlined | 1. | If amplifier is proven at fault, |
Minimum Discharge |
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| in “Preliminary Circuit |
| install replacement amplifier. |
Air Temperature. |
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| Analysis” in Section IX. |
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| 2. | Short in T244 or | 2. | Remove wires connected | 2. | If reading is incorrect, replace |
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| TS244/TD244 circuit. |
| to amplifier terminals 4 & 5. |
| The T244,TS244/TD244 or |
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| Set T244 or TD244 to max- |
| repair wiring. |
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| imum setting. Measure |
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| resistance across wires. |
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| Meter should read 6000 |
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| ohms ± 1000 (T244). If |
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| TS244/TD244 are used, |
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| meter should read 4500 |
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| ohms ± 1000 (TS244) and |
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| 2100 ohms ± 150 (TD244). |
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Control circuits external to Series 44 can cause burner malfunction. Always check manual valve to be certain gas is on, and check limit controls for normal operation.
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