White Rodgers 1F85ST-0422 User Manual

The White Rodgers 1F85ST-0422 is a programmable electronic digital thermostat with Spanish display for single-stage, multi-stage, or heat pump systems with automatic heat/cool changeover option. It features 5+1+1 or 5+2 day programming, installer configuration menu, and energy-saving features like Cool Savings. Battery-powered with 2 AA batteries; compatible with 24V systems up to 1.5A per terminal. Below are the key specifications, installation, operation, programming, and troubleshooting instructions.

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 millivolt or line voltage. Install away from drafts, direct sunlight, or heat sources for accurate sensing. Note: Display shows Spanish text.

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.

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.thermostat-recycle.org for disposal.

Description

The thermostat consists of cover and base. Features LCD display showing time/room temperature alternating with set point (in Spanish), up/down arrows for adjustment, SYSTEM switch (COOL/OFF/HEAT/EMER), FAN switch (ON/AUTO), O/B switch for changeover (factory "O" for COOL energized). Terminals: R, C, Y, Y2, G, W/E, W2, O/B, L. Supports heat pump with/without aux/emergency heat, up to 2-stage heat/cool, heat-only/cool-only systems.

Applications: Heat Pump (No Aux/Emergency Heat): Yes; Heat Pump (with Aux/Emergency): Yes; Standard Heat/Cool: No; Heat Only: Yes (optional fan); Millivolt Heat Only: Yes; Cool Only: Yes; Gas/Oil Heat: Yes; Electric Furnace: Yes; Hydronic 2/3 Wires: Yes.

Precautions

CAUTION! To prevent electrical shock/equipment damage, disconnect power at main fuse/circuit breaker until installation complete. Label wires prior to disconnection.

WARNING! Do not use on circuits exceeding 20-30 VAC 50/60 Hz or DC (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.

CAUTION! Below 50°F, do not operate cooling (compressor damage). For electric heat/single-stage heat pump, set GAS/ELEC if fan energizes on heat call. For hydronic, clip W905 for longer cycles.

Specifications

• Electrical: Battery Power mV to 30 VAC, NEC Class II, 50/60 Hz or DC; Input-Hardwire 20-30 VAC; Terminal Load 1.5A per terminal, 2.5A max all terminals.
• Setpoint Range: 45°F to 90°F (7°C to 32°C).
• Rated Differentials: Heat (SS1, MS2) Fast 0.4°F/Med 0.6°F/Slow 1.7°F; Cool (SS1, MS2) Fast 0.9°F/Med 1.2°F/Slow 1.7°F; Heat Pump (HP1, HP2) Fast 0.9°F/Med 1.2°F/Slow 1.7°F; Emer (HP1, HP2) 0.6°F to 1.7°F.
• Operating Ambient: 32°F to 105°F (0°C to 41°C).
• Humidity: 90% non-condensing max.
• Shipping: -40°F to 150°F (-40°C to 65°C).
• Dimensions: 3-7/8”H x 5-1/8”W x 1-1/4”D.

Removing Old Thermostat

A standard heat/cool thermostat consists of three basic parts: 1) Cover (snap-on/hinge type); 2) Base (loosen captive screws); 3) Switching subbase (unscrew from wall/adaptor). Label each wire with terminal designation before disconnecting. Disconnect wires one at a time; do not let fall into wall. If wall mounting plate exists, remove thermostat and plate as assembly.

Installation

Pull thermostat body off base (do not force/pry). Place base over wall hole, mark mounting holes, drill, fasten with screws (level for appearance). Connect wires to terminals. Push excess wire into wall, seal hole with fire-resistant material (e.g., fiberglass). Snap cover on.

Batteries: 2 AA alkaline (replace every 2 years; low shows battery icon/"Change Battery"). Insert positive (+) to right. For unoccupied homes >3 months, replace if icon displayed. Offset occurs when <2 months life remains (±10°F); reset manually.

Wiring Diagrams

Terminal Designations: L (malfunction indicator), O (changeover COOL), B (changeover HEAT), Y (compressor), Y2 (2nd stage compressor), W/E (heat/emergency relay stage 1), W2 (2nd stage heat/HP1), G (fan), RH (heating power), RC (cooling power), C (common), 6 (3-wire zone valve).

Single Transformer Systems: R to 24VAC hot, C to neutral, Y to compressor, G to fan, W2 to aux (stage 2), E to emergency, O/B to changeover (energized in COOL if "O"). Jumper for single aux both stages.

Two Transformer (No Safety Circuits): Separate transformers; jumper commons. Polarity observed; cut/tape unused.

Two Transformer (Safety in Both): Accessory relay N.O. for safety; jumper commons.

CAUTION! Refer to equipment manuals for specifics. Tighten securely; keep wires clear.

Check Operation

Touch side to release static before keys. Restore power. If system fails, contact serviceperson.

Fan Operation

1. Power on.
2. FAN ON: Blower operates.
3. FAN AUTO: Blower stops.

Heating System

1. SYSTEM HEAT; light pilot if standing.
2. Adjust 1° above room: Heat pump operates ("System On", flashing if lockout).
3. Adjust 4° above: Aux (stage 2) operates, "+2" flashing.
4. Adjust below: Stops.

Emergency System

1. SYSTEM EMER ("EMER" flashes).
2. Adjust above: Aux operates, "+2" flashing.
3. Adjust below: Stops.

Cooling System

CAUTION! Do not operate below 50°F.

1. SYSTEM COOL.
2. Adjust below room: Blower high, then cool ("System On").
3. Adjust above: Stops.

Operating Features

• Home Screen: System On (+2 for stage 2), HOLD/Temp HOLD, Change Filter, Set, System Mode, Fan Mode, Run Sched/Schedule/Menu, Save (Cool Savings), Heat Pump, Hold/Light Bulb, Auto Sched/Cool Savings, Call For Service, Time/LOC (lockout), P (screen #). Display in Spanish.
• Keypad Lockout: Lk L (on), 001-999 code.
• Cool Savings: 1-6 levels or off (0).
• Energy Management Recovery: On/off (1F85 only).
• Display Light: On/off.
• Ambient Adjustment: ±4°F.
• Range Limits: Heat 62-89°F, Cool 46-82°F.

Programming

Factory preprogrammed; RESET (back) to restore. 5+1+1 or 5+2 day; 4 periods/day.

1. Set Time/Day: Hold SET TIME, adjust hour/min/day.
2. Program: Hold PRGM, select day/group, adjust period time/temp (heat/cool shared times).
3. Copy: After Mon, hold COPY to all days.
4. Review: Hold PRGM to cycle.
5. Run: RUN PRGM.
6. Hold: Hold HOLD for indefinite; Temp Hold for temporary.

Factory Heat: Wake 6AM 70°F, Leave 8AM 62°F, Return 5PM 70°F, Sleep 10PM 62°F. Cool: Wake 74°F, Leave 80°F, Return 74°F, Sleep 78°F.

Installer Configuration

SYSTEM to HEAT/COOL/EMER/AUTO; hold MENU 5s. Press MENU to advance; up/down to change.

Troubleshooting