Your new White Rodgers 1F84-51 is a 7-day programmable electronic digital thermostat for heat pump systems. It uses solid-state microcomputer technology for precise time/temperature control, with separate programs for each day, simultaneous heat and cool setpoint storage, and four time/temperature settings per 24 hours. Compatible with 24V systems only; not for millivolt or line voltage. Below are the key specifications, installation, operation, programming, and troubleshooting instructions.
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 is complete. Label wires before disconnecting. This thermostat is for 24V heat pump systems only; not for millivolt, line voltage, or systems over 30 VAC/1.5 amps.
The thermostat consists of a cover and base. Features include LCD display showing set point alternating with time/room temperature, up/down arrows for adjustment, SYSTEM switch (COOL/OFF/HEAT/EMER), FAN switch (ON/AUTO), O/B switch for changeover relay (factory "O" for COOL energized). Terminals: R, C, Y, G, W2, E, O/B. 8 terminals for single/two-transformer systems. Armchair programming without removing cover.
WARNING! Do not use on circuits exceeding 20-30 VAC 50/60 Hz or DC; higher voltage damages control and causes shock/fire. Do not short terminals on gas valve/primary control to test; incorrect wiring burns out components, causes injury/property damage. Conform to NEC Class II circuits. Disconnect power before installation.
CAUTION! Below 50°F, do not operate cooling (compressor damage). Handle carefully; rough handling causes malfunction. For electric heat/single-stage heat pump, set GAS/ELEC switch if fan energizes on heat call. For hydronic, clip W905 for longer cycles.
| Category | Details |
|---|---|
| Electrical Rating | 20-30 VAC 50/60 Hz or DC; 0.05-1.5 Amps per terminal; 1.5 Amps max total load |
| Setpoint Range | 45°F to 90°F (7°C to 32°C) |
| Operating Ambient | 32°F to 105°F |
| Humidity | 0-90% RH non-condensing |
| Shipping Temperature | -40°F to 150°F |
A standard heat/cool thermostat has three parts: cover (snap-on/hinge), base (loosen captive screws), switching subbase (unscrew from wall/adaptor). Remove cover, note/label wires, disconnect one by one (do not let fall into wall). If wall plate exists, remove assembly.
Gently pull cover off base. Set O/B to "O" (default) or "B" as needed. For slow cycle, clip W905; for Celsius, clip W904. Connect wires per diagrams. Place base over wall hole, mark/drill mounting holes, secure with screws (level for appearance). Push excess wire into wall, seal hole with fire-resistant material. Snap cover on.
Batteries: 2 AAA alkaline (replace yearly; low battery shows "BATT"). Install positive (+) to right.
Single Transformer Systems (Fig. 2): R to 24VAC hot, C to neutral, Y to compressor contactor, G to fan relay, W2 to aux relay (stage 2), E to emergency relay, O/B to changeover relay (energized in COOL if "O"). Jumper if single aux for both stage 2/emergency.
Two Transformer Systems (No Safety Circuits, Fig. 3): Separate transformers for heat pump/aux; jumper commons. Cut/tape off unused. Polarity must be observed.
Two Transformer Systems (Safety Circuits in Both, Fig. 4): Accessory relay N.O. contact for safety; jumper commons.
CAUTION! Tighten securely; keep wires clear. For systems without G, skip fan wiring.
Touch side to release static before keys. Restore power. If system fails, contact qualified serviceperson.
CAUTION: Do not operate below 50°F.
Factory preprogrammed; use RESET (back of thermostat) to restore if needed. Program per day: 4 periods, shared times for heat/cool.
Factory: Heat (6AM 70°F, 8AM 62°F, 5PM 70°F, 10PM 62°F); Cool similar but higher temps.
| Symptom | Possible Cause | Corrective Action |
|---|---|---|
| No Heat/Cool/Fan | Blown fuse/tripped breaker; power switch OFF; loose door/panel. | Replace/reset; turn ON; secure panel. |
| No Heat | SYSTEM not HEAT; loose wires; system needs service. | Set to HEAT, raise temp; secure wires; test/service system. |
| No Cool | SYSTEM not COOL; loose wires; system needs service; below 50°F. | Set to COOL, lower temp; secure wires; test/service; wait if cold. |
| Constant Run | Short in wiring/thermostat/system; FAN ON. | Check connections; set FAN AUTO. |
| Fast/Slow Cycles | Location/system size; fixed anticipator. | Relocate; contact service for adjustments. |
| Display Issues | Low batteries; voltage loss. | Replace AAA batteries. |
| Compressor Lockout (Flashing Icons) | Cycling too quick. | Wait 5 min for reset. |