Modine Manufacturing MPR - Table 52.1 - Troubleshooting (Continued)

52 MCP15-500.7
Table 52.1 - Troubleshooting (Continued)
SERVICE & TROUBLESHOOTING - CONTINUED
I. Electric Heat Not
Functioning
1. See Problem “A” 1. See Problem “A”
2. See Problem “D” 2. See Problem “D”
3. Thermostat not calling for heat 3. Check and wait or override
4. Limit switches are open 4. Check and correct
5. Overload relay is tripped 5. Check and correct
6. Failed heat modules 6. Check and replace
J. Gas Heat Not
Functioning Properly
1. See Problem “A” 1. See Problem “A”
2. See Problem “D” 2. See Problem “D”
3. Thermostat not calling for heat 3. Check and wait or override
4. Limit switches are open 4. Check and correct
5. Main gas supply not turned on 5. Check and correct
6. Air in gas line 6. Purge per instructions
7. Loose wiring to ignition controls or gas valves 7. Check and tighten
8. Failed ignition controller or gas valve 8. Check and replace
9.Failedamesensor 9. Check and replace
10. Improper supply air temperature sensor installation 10. Check and correct
11.Flamerolloutorashback
11a. Main pressure too high (correct to 14” W.C. max)
11b.Oricetoolarge(verifytheymatchtheserialplate)
11c. Manifold pressure too low (reset)
12. Not enough heat
12a.Unitcyclingonhighlimit(checkairow)
12b. Main pressure too low (must be 6” W.C. minimum)
12c. Unit undersized for conditions
12d. Improper supply air temperature sensor installation
13. Too much heat
13a. Manifold pressure too high (correct to 3.5” W.C.)
13b. Defective or improperly wired controls
14. Clogged condensate drain line (94% and 90% gas
heat option only)
14. Check condensate drain line, clear as required.
Trouble Possible Cause Possible Remedy
F. Compressor(s)
Do Not Operate
1. See Problems “A” and “B” 1. See Problems “A” and “B”
2. Controls are in Unoccupied mode 2. Wait for Occupied mode or override
3. Ambient lockout 3. Check and wait or override
4. Low pressure lockout 4. Check and wait or override
5. High pressure lockout 5. Check and wait or override
6. Inter-stage delay 6. Check and wait or override
7.Airowprovingswitchnotclosing 7. Check and correct
8. Thermostat not calling for cooling 8. Check and wait or override
9.Drainpanoatswitchopen 9. Check switch, check drain line (pan, trap, piping) for
proper drainage, and verify trap is primed with water
G. Compressor(s)
Do Not Cycle Off
1.Supplyairtemperaturenotsatised 1. Compressors will remain on until the supply air setpoint
issatised
H. Dampers Do Not
Operate
1. See Problem “A” 1. See Problem “A”
2. Failed damper motor(s) 2. Check and replace
3. Loose wiring to damper motor(s) 3. Check and tighten
4. Controls are in Unoccupied mode 4. Wait for Occupied mode or override
5. Ambient lockout 5. Check and wait or override