White Rodgers 37-7248A Installation, Wiring Connections, Remove Old Thermostat, Batteries

Models: 37-7248A

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INSTALLATION

INSTALLATION

!WARNING

Thermostat installation and all components of the control system shall conform to Class II circuits per the NEC code.

Remove 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 adapter plate. Before removing wires from old thermostat, label each wire with the terminal designation from which it was attached. Disconnect the wires from the old thermo- stat one at a time. Do not let wires fall back into the wall.

Batteries

2 "AA" alkaline batteries are included in the thermostat. To in- stall the batteries, pull the battery door as shown by the arrow and lift open. Using the polarity indicated inside the battery door, insert the batteries. To close the battery door, swing the door down while pulling in the direction of arrow. Once fully down, snap the door back into position.

To replace the batteries, set system to OFF, following the instructions above.

Figure 1 – Battery door shown open

Remove Old ThermostatBatteries “AA” Alkaline Batteries

Installing New Thermostat

1.Pull the thermostat body off the thermostat base. Forcing or prying on the thermostat will cause damage to the unit.

2.Place base over hole in wall and mark mounting hole locations on wall using base as a template.

3.Move base out of the way. Drill mounting holes. If you are using existing mounting holes and the holes drilled are too large and do not allow you to tighten base snug- ly, use plastic screw anchors to secure the base.

4.Fasten base snugly to wall using mounting holes shown in Figure 2 and two mounting screws. Leveling is for appearance only and will not affect thermostat operation.

5.Connect wires to terminal block on base.

6.Push excess wire into wall and plug hole with a fire re- sistant material (such as fiberglass insulation) to prevent drafts from affecting thermostat operation.

7.Carefully line the thermostat up with the base and snap into place.

SS/HP Switch

(Conventional or Heat Pump Selection)

The SS/HP switch is factory set to the SS position. In this posi- tion, thermostat is configured as conventional single stage. If you have a single stage heat pump system, switch SS/HP to HP position (see figure 2).

Gas/Elec Switch (Fan Option)

The GAS/ELEC switch is factory set to the GAS position. In this position, the thermostat will not power the circulator fan on a call for heat, but will power the circulator on a call for cool.

If your system requires that the thermostat power the circula- tor fan on a call for heat, this switch should be set to the ELEC position. Typically, gas and oil heating systems do not require the thermostat to power the circulator fan during a call for heat. If your heat is gas or oil, the switch should be set to the GAS position.

When the thermostat is configured for Heat Pump, the thermo- stat will always power the circulator fan on a call for heat in the HEAT mode.

Thermostat can be powered by system AC power or Battery.

If Installing New Thermostat is displayed, the thermostat is battery powered. If

SS/HP Switch is not displayed, thermostat is system powered with optional battery back-up. When battery power remaining is

approximately half, the Gas/Elec Switch (Fan Option) will be displayed. When "Change WIRING CONNECTIONS" is displayed, install fresh “AA” alkaline batteries imme- diately. For best results, replace all batteries with a premium brand alkaline battery such as Duracell® or Energizer®. We recommend replacing batteries every 2 years. If the home

is going to be unoccupied for an extended period (over 3

months) and Manual background is displayed, the batteries should be re- placed before leaving. When less than two months of battery life remain, the setpoint temperature will offset by 10 degrees (10 degrees cooler in Heat mode / 10 degrees warmer in Cool mode). If offset occurs, the normal setpoint can be

manually reset with Manual backgroundManual background or Manual background. Another offset will occur within two days if batteries are not replaced.

Figure 2 – Thermostat base and rear view of thermostat

Mounting

 

 

Mounting

Hole

 

 

 

 

 

 

 

Hole

 

 

 

 

 

Place Level

 

 

Place Level

across

 

 

 

 

 

 

across

 

 

 

 

 

Mounting Tabs

 

 

Mounting Tabs

(for appearance only)

(for appearance only)

SS/HP

SS

GAS

 

 

HP

ELEC

Switch

 

 

GAS/ELEC Switch

WIRING CONNECTIONS

Refer to equipment manufacturers' instructions for specific system wiring information. After wiring, see CONFIGURATION section for proper thermostat configuration. Refer to 37-6754 wiring diagram specifications.

TERMINAL DESIGNATION DESCRIPTIONS

Terminal Designation

Description

Terminal Designation

Description

O/B

(SS) Power closed for 3 wire zone

RH

Power for Heating

 

.HP) Changeover valve for heat pump

RC

Power for Cooling

Y

Compressor Relay

C

Common wire from secondary side of

W

Heat Relay

 

.cooling system transformer or heat

G

Fan Relay

 

.only system transformer

 

 

 

 

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White Rodgers 37-7248A Installation, Wiring Connections, Remove Old Thermostat, Batteries, Installing New Thermostat