White Rodgers 1D51 User Manual

Your new White Rodgers 1D51 Thermostat is a low voltage cooling thermostat with sub-base for system and fan selection. It is designed for standard central air conditioning systems. Below are the key specifications, installation, operation, and troubleshooting instructions.

1. Preparations 2. Thermostat Replaces 3. Removing Old Thermostat 4. Mounting and Wiring 4.1 Wiring Diagrams 5. Check Operation 5.1 Fan Operation 5.2 Cooling System 6. Operating Features 7. Specifications 8. Troubleshooting

Preparations

Assemble tools required: power drill, flat blade screwdriver, wire cutter/stripper, level.

Failure to follow and read all instructions carefully before installing or operating this control could cause personal injury and/or property damage.

CAUTION! To prevent electrical shock and/or equipment damage, disconnect electrical power to the system at the main fuse or circuit breaker until installation is complete.

Before removing wires from old thermostat’s switching subbase, label each wire with the terminal designation it was removed from.

WARNING! Do not use on circuits exceeding specified voltage. Higher voltage will damage control and could cause shock or fire hazard. Thermostat installation and all components of the system shall conform to Class II circuits per the NEC code.

Thermostat Replaces

SystemModels
Standard Central Air Conditioning
Cool Only Systems – 2 wires		All Models
Standard Heating & Cooling Systems – 4 or 5 wires
Gas or Oil Heat
Hydronic (Hot Water) Zone Heat		None

Removing Old Thermostat

A standard heat/cool thermostat consists of three basic parts:

  1. The cover, which may be either a snap-on or hinge type.
  2. The base, which is removed by loosening all captive screws.
  3. The switching subbase, which is removed by unscrewing the mounting screws that hold it on the wall or adaptor plate.

Remove base from subbase: Loosen the screws on the base and remove it from the wall. Do not remove wires at this time.

Mounting and Wiring

Mount switching subbase: Use the screws provided to mount the subbase and adaptor plate (optional) to wall.

Wiring Diagrams

Figure 2. Typical wiring for single transformer cooling system

For two-wire cool only system, attach one wire to RC and one to Y. Leave the factory installed jumper between RC and RH attached. Tighten any unused terminals securely.

Figure 3. Typical wiring for cool only, 2-wire

  1. Connect wires to appropriate terminals.
  2. Mount thermostat base to subbase using the three captive screws. Tighten securely. Remove paper tag from plastic contact cover.

CAUTION! To prevent electrical shock and/or equipment damage, disconnect electrical power to the system at the main fuse or circuit breaker until installation is complete. Keep this area clear of wires.

Check Operation

Contact service if not operating properly.

Fan Operation

  1. FAN ON, blower on.
  2. FAN AUTO, off.

Cooling System

CAUTION: Below 50°F, DO NOT operate.

  1. SYSTEM COOL.
  2. Adjust below room temp, blower then cool.
  3. Adjust above, stops.

Operating Features

Specifications

Troubleshooting

SymptomPossible CauseCorrective Action
No Cool/No Fan1. Blown fuse or tripped circuit breaker.
2. Cooling system power switch to OFF.
3. Blower compartment door loose.		Replace fuse or reset breaker. Turn switch to ON.
Replace door panel properly.
No Cool1. Loose connection to thermostat or system.
2. Thermostat or cooling system requires replacement or service.
3. System Switch not set to Cool.		Verify wires securely attached.
Test cooling system; replace if needed.
Set System Switch to Cool and lower temp below room temp.
Constant RunPossible short in wiring or thermostat.Check wiring connections.
Cooling Cycles Too Fast or Too SlowPoor thermostat location.Relocate if needed.
Thermostat Setting and Thermometer DisagreeCalibration needed.Adjust thermometer pointer inside cover.
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