White Rodgers Comfort-Set 1F95-377 User Manual

The White Rodgers 1F95-377 is a premium 7-day programmable digital thermostat from the Comfort-Set 90 Series for multi-stage heat/cool or heat pump systems with electric or fossil fuel auxiliary. It features 7-day programming with 4 periods per day, automatic/manual changeover, humidifier and dehumidifier control, wireless remote sensors (up to 3 indoor), outdoor sensor support, and service reminders. Powered by 24 VAC (requires hot and common); compatible with systems up to 1.5A per terminal, 2.5A max total. Below are the key specifications, installation, operation, programming, and troubleshooting instructions.

1. Preparations 2. Description 3. Precautions 4. Specifications 5. Installation 5.1 Wiring Diagrams 6. Check Operation 6.1 Fan Operation 6.2 Heating System 6.3 Emergency System 6.4 Cooling System 7. Operating Features 8. Programming 9. Installer Configuration 10. Troubleshooting

Preparations

Assemble tools: hand or power drill with 3/16 inch drill bit (if needed), flat blade screwdriver, wire cutter/stripper, level. Shut off electricity at main fuse box until installation complete. Label wires before disconnecting. This thermostat is for 24V systems only; not for line voltage. Install away from drafts, direct sunlight, or heat sources for accurate sensing.

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

Description

The thermostat uses solid-state microcomputer technology to provide precise time, humidity, and temperature control. Features 7-day programming with four time/temperature settings per day, simultaneous heat/cool programs, up to 3 stages heat/2 stages cool, humidifier control (HM), dehumidifier control (DHM), wireless remote sensors (up to 3 indoor via SA/SB/SC), outdoor sensor (OT), automatic changeover, compressor protection, service reminders. LCD display shows time/room temp/setpoint/humidity, up/down arrows, SYSTEM switch (HEAT/OFF/COOL/AUTO/EMER), FAN switch (ON/AUTO). Terminals: R (hot), C (common), G (fan), O/B (changeover), Y1/Y2 (compressor stages), W1/W2/W3 (heat stages), HM (humidifier), DHM (dehumidifier), L (fault), SA/SB/SC (remote sensors), OT (outdoor).

Applications: Multi-Stage Heat Pump: Yes; Heat Pump with Aux/Emergency: Yes; Multi-Stage Conventional: Yes; Single-Stage Heat/Cool: Yes; Heat Only: Yes; Cool Only: Yes; Gas/Oil/Electric/Hydronic: Yes; Millivolt: No.

Precautions

CAUTION! To prevent electrical shock/equipment damage, disconnect power at main fuse/circuit breaker until installation complete. Label wires prior to disconnection. If in doubt about wiring, consult qualified heating/air conditioning contractor.

WARNING! Do not use on circuits exceeding 20-30 VAC 50/60 Hz (0.05-1.5A per terminal, 2.5A max total); higher voltage damages control/causes shock/fire. Do not short terminals on gas valve/primary control to test; short/incorrect wiring burns out components/causes injury/property damage. Conform to NEC Class II circuits. Do not operate cooling below 50°F (compressor damage).

ATTENTION! This product does not contain mercury but may replace one that does. Do not open mercury cells; if damaged, wear non-absorbent gloves, clean up spilled mercury, place in sealed container. Refer to www.white-rodgers.com for disposal. Handle to avoid static discharge.

Specifications

Removing Old Thermostat

A standard heat/cool thermostat consists of three basic parts: 1) Cover; 2) Base; 3) Subbase. Label each wire with terminal designation before disconnecting. Disconnect wires one at a time; do not let fall into wall.

Installation

Remove old thermostat. Mount new base level on wall, connect wires to terminals. Push excess wire into wall, secure base, attach thermostat body. Power up and configure.

Wiring Diagrams

Terminal Designations: R (24V hot), C (common), Y1/Y2 (compressor stages), G (fan), W1/W2/W3 (heat stages), O/B (changeover), HM (humidifier), DHM (dehumidifier), L (fault), SA/SB/SC (remote sensors), OT (outdoor sensor).

Single Stage Heat/Cool: R to hot, C to common, Y1 to compressor, G to fan, W1 to heat.

Multi-Stage (MS2): Add Y2 2nd compressor, W2/W3 2nd/3rd heat.

Heat Pump (HP1/HP2): Y1/Y2 compressor, O/B changeover (O cool, B heat), W1/W2/W3 aux heat.

Humidifier: HM to humidifier relay; 24V or 120V setups.

Dehumidifier: DHM to relay for fan speed control.

Remote Sensors: SA/SB/SC for indoor wireless, OT for outdoor.

CAUTION! For single transformer systems. Refer to equipment manuals for specifics.

Check Operation

Restore power. Set SYSTEM to HEAT/COOL, FAN to ON/AUTO, adjust setpoint to test.

Fan Operation

  1. FAN ON: Blower runs continuously.
  2. FAN AUTO: Blower runs on call for heat/cool.

Heating System

  1. SYSTEM HEAT.
  2. Setpoint above room temp: Heat activates (LED indicators for stages).
  3. Setpoint below: Heat stops.

Emergency System

  1. SYSTEM EMER (red LED).
  2. Setpoint above: Aux operates.
  3. Setpoint below: Stops.

Cooling System

CAUTION! Do not operate below 50°F.

  1. SYSTEM COOL.
  2. Setpoint below room temp: Cool activates (5-min delay first time).
  3. Setpoint above: Cool stops.

Operating Features

Programming

7-day programming; 4 periods (MOR/DAY/EVE/NHT). Factory preprogrammed; press PROGRAM + RUN to start.

  1. Set Time/Day: Press SET TIME ± for hour/min, SET DAY for day.
  2. Program: Select HEAT/COOL, press PROGRAM for period, TIME/TEMP ± to set.
  3. Copy: Hold COPY to duplicate day/period.
  4. Review: Press PROGRAM to cycle through.
  5. Run: Press RUN.
  6. Hold: Press HOLD for permanent; temporary override available.

Factory Heat: All days: 6AM 70°F, 8AM 62°F, 5PM 70°F, 10PM 62°F. Cool: All days: 6AM 78°F, 8AM 85°F, 5PM 78°F, 10PM 82°F.

Installer Configuration

Press TIME FWD + TIME BACK to enter User menu, then hold SET TIME + SET DAY for 3 sec to enter Installer menu. Use UP/DOWN to adjust, TIME FWD to advance.

StepDisplay (Default)OptionsComments
1MLTI STG / HEAT PUMPMLTI STG / HEAT PUMPSelect system type
2HEAT PUMP (1)1 / 2Compressor stages (HP only)
3ELEC HEAT FAN (ON)OFF / ONFan control for electric heat
4SET CYCL (05)1-40Heat cycle rate
5SET CYCL (12)9-40Cool cycle rate
6SET CYCL AUX (08)1-40Aux heat cycle (HP only)
7COOL FAN DELA OFF (00)0-127 secCool fan off delay
8FAN DELA ON (01)1-30 secFan on delay
9HEAT FAN DELA OFF (00)0-127 secHeat fan off delay
10PUMP (ON)OFF / ONPump lockout (HP fossil fuel)
11COMP OFF DELA (60)0-? secCompressor off delay
12CR COMF (ON)OFF / ONComfort recovery
13STG 3 HP (OFF)OFF / ON3rd stage HP
14bbPOFF / ONLockout bypass (service only)
15Ser uView/SetService reminders

Troubleshooting

SymptomPossible CauseCorrective Action
Display BlankPower loss.Check transformer/wiring; restore power.
CHECK SYSSystem not responding (no heat rise in 2 min).Retries; check system, wiring.
CHECK STATStuck key, sensor failure.Press PROGRAM; power cycle.
Heating/Cooling Not WorkingWrong mode, setpoint, wiring.Set correct mode/setpoint; verify wires.
Fan Not RunningAUTO no call; wiring.Set ON; check G terminal.
Short CyclingCycle rate setting.Adjust in menu.
Compressor Won't Start5-min lockout.Wait; check indicators.
Humidity IssuesSetpoint, wiring to HM/DHM.Verify humidifier/dehumidifier setup.

Reset Operation: Remove wires from R and C (do not short), power cycle 2 min. Resets to factory defaults.

Homeowner Help Line: 1-800-284-2925; www.white-rodgers.com

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