C.Gas Pressure Switches - Operate unit in Heat mode. The low pressure switch will trip out and must be reset before resuming operation when the inlet gas valve is turned off during operation.The high pressure switch may be checked out by reducing the setting of its trip point below unit operating pressure. It should then trip out and shut off the burner. Return the adjustment to its original setting and reset to resume operation.
When checking operation of gas pressure switches on systems without pilot the heat switch will have to be turned off for approximately five seconds to reset the ignition control.
D.Air Pressure Switches - The high air pressure switch is checked by removing the sensing tube from the enter- ing air side of the burner. Switch operation will shut off the burner. Recycle is automatic when the sensing tube is replaced.The low air pressure switch is checked by removing the sensing tube from the leaving air side of the burner. Switch operation will shut off the burner. Recycle is automatic when the sensing tube is replaced.
When checking operation of air pressure switches on systems without pilot the heat switch will have to be turned off approximately five seconds to reset the igni- tion control.
E.Temperature Controls – These controls are checked by adjusting control settings to a lower temperature setting while the unit is operating on high fire and observing cutoff. The controls should be reset to settings shown below:
| Suggested Control Settings | |||
Room Thermostat | Customer Discretion | |||
| 65°F | |||
Freeze Thermostat |
| 3 min.,...45°F | ||
Low Gas Pressure Switch | 1.0”w.c | |||
High Gas Pressure Switch |
| 125% of firing rate | ||
Night Set Back Room | Customer Discretion | |||
Remote Temperature Selector .... | Customer Discretion | |||
High Temperature Limit (manual) | ........ Not adjustable | |||
High Limit Discharge Ductstat | ................................ | 95°F | ||
Low Limit Discharge Ductstat | ................................ | 55°F | ||
Clogged Filter Switch | Adjust to Field Conditions | |||
Building Pressure Switch .. | Adjust to Field Conditions |
SECTION VI - UNIT SHUTDOWN
A. Extended Shutdown - | B. Emergency Shutdown ONLY - |
1.Set the Heat OFF/ON switch to the OFF, then turn the Fan switch to the OFF position.
2.Close all manual gas valves.
3.Open the main electrical disconnect switch.
1.Open the main electrical disconnect switch.
2.Close all manual gas valves.
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