Emerson White-Rodgers 1F97-1277 Touchscreen Thermostat (Mammo Room)
Setup, the Farber standard configuration for mammography-coach room thermostats (setpoints, lockout code 150), wiring for single-stage and heat-pump systems, the installer configuration menu, and troubleshooting including Comfort Alert fault codes and the reset procedure.
Overview
The Emerson (White-Rodgers) 1F97-1277 is a universal single-stage touchscreen thermostat with automatic heat/cool changeover, used on Farber specialty coaches that carry conventional 24 VAC split systems - typically the mammography units, which run two of them (a forward/driver-side stat and a rear/passenger-side stat). It supports two system types selected in the installer menu: SS1 (single-stage gas, oil, electric, or hydronic zone) and HP1 (single-stage compressor heat pump with auxiliary/emergency heat). Setpoint range is 45-99 F; terminal load limit is 1.5 A per terminal, 2.5 A total.
Power and installation
The stat runs on two AA alkaline batteries with optional 24 VAC hardwire (C terminal) or power-stealing assist. Pull the battery tag on first use. Leave the two power-stealing switches on the back ON for most systems; if a high-impedance furnace board misbehaves (inducer or blower running with no call, equipment not dropping out), switch them OFF and run on batteries. Mark the old thermostat's wires before removal. Mount the base, land the wires, plug the wall hole with fire-resistant material so drafts do not fool the sensor, and snap the body on. Terminals: RC and RH (24 V cooling/heating power), C (common - required for a remote sensor), Y (compressor / cool call), W/E (heat call; second-stage or emergency heat in HP1), G (fan), O/B (reversing valve - O energizes in cool, B in heat, chosen in the menu), 6 (SPDT three-wire zone valve), L (heat-pump fault indicator), and +, S, - for one wired remote sensor (indoor F145-1328 or outdoor F145-1378, up to 300 feet).
Installer configuration menu
Press Menu, then press and hold Installer Config about five seconds. Screen-reference numbers show in the top-right corner; the up arrow advances items, left/right change values. Key items: 1 system type SS1/HP1; 2 GAS (furnace controls blower) or ELE (thermostat controls blower - note a factory reset flips this back to GAS); 3 reversing valve O or B (HP only); 4 programs per week 7 / 5+1+1 / 0 (non-programmable); 12 compressor lockout (5-minute delay between cool cycles - the setpoint flashes while it counts down); 14 display calibration +/-5 F; 24 and 25 heat/cool setpoint limits; 26 keypad lockout (L total, P partial, or temperature-limit only); 27 the lockout combination; 28-30 remote-sensor enable and local-sensor disable; 31-35 dual-fuel and auxiliary-heat options for heat pumps. To restore factory defaults press the up, down, and SYSTEM keys simultaneously - the display blanks, then all segments light.
Farber standard configuration (mammo coaches)
Farber deliberately runs these stats non-programmable, locked, and in Auto changeover so clinic staff cannot reprogram them. Set and verify:
- Main A/C stat (forward / driver's side): Cool 72 F, Heat 69 F, Fan Auto.
- Second A/C stat (rear / passenger side): Cool 74 F, Heat 67 F, Fan Auto.
- Installer config: 02 System Type Gas (default) - 04 Programs Per Week 0 (change from the default 7) - 12 Compressor Protection Off (default) - 24 Heat Range Stop 90 (default) - 25 Cool Range Stop 50 (default) - 26 Keypad Lockout L (total lock; default is Off) - 27 Lockout Combination 150 (default 000).
- Finish with SYSTEM set to Auto. After exiting the menu the lock engages in about ten seconds, during which the SYSTEM key stays live - verify Auto within that window.
To unlock a locked stat: press Menu, press and hold Installer Config until the keypad-lock screen appears, dial the three-digit code to 150 with the left/right keys, and press up to unlock. Set temperatures via the SYSTEM box (select Heat or Cool, adjust, then return the system to Auto). Relock via items 26 and 27 as above. If the code has been changed and lost, holding the Menu key about 20 seconds force-unlocks the stat.
Operation notes
Auto changeover picks heat or cool automatically; program cooling at least 1 F above heating. Pressing SYSTEM to Auto resumes whichever mode ran last - press both arrow keys together to jump to the other mode. Fan Auto runs the blower only with a call (plus cooling); Fan On is continuous; Fan Prog cycles the fan 10 minutes on / 20 off when the system has been idle an hour. In HP1, Em (emergency) mode bypasses the compressor and heats only on the W/E source. A flashing setpoint means the 5-minute compressor lockout timer is running - wait, do not diagnose. Do not run cooling below 50 F outdoors, and never start a compressor until its crankcase heater has been powered 6 hours and the system has been off at least 5 minutes.
Comfort Alert diagnostics
If the outdoor unit carries a Comfort Alert module (Copeland Scroll systems), its flash codes repeat on the stat as a flashing Call For Service: 1 long run time, 2 system pressure trip, 3 short cycling, 4 locked rotor, 5 open circuit, 6 open start circuit, 7 open run circuit, 8 welded contactor, 9 low voltage. With the Comfort Alert feature ON the stat also shuts the compressor down protectively. Call For Service always indicates a fault in the HVAC equipment, not in the thermostat itself.
Maintenance schedule
| Task | Interval | Parts | Notes |
|---|---|---|---|
| Replace the two AA alkaline batteries | 12 months | AA-ALK AA alkaline battery | Annually at coach service, or immediately when the half-power battery icon shows. Set SYSTEM to Off before pulling the stat off its base. Use premium alkaline cells. Farber recommended - a dead stat in a clinical coach takes the room's climate down. |
| Verify Farber standard configuration and keypad lock | 6 months | — | Farber recommended each service visit: setpoints 72/69 forward and 74/67 rear, Fan Auto, SYSTEM Auto, programs-per-week 0, keypad lockout L with combination 150. Batteries out for 2+ minutes or a factory reset can revert options (item 02 flips back to GAS on reset) - reconfirm after any reset. |
| Check thermostat calibration against a reference thermometer | 12 months | — | Farber recommended annually for clinical rooms. Display can be trimmed +/-5 F at installer menu item 14 (manual states +/-4 in troubleshooting text; use the menu range). |
| Exercise heat, cool, and fan from the stat and confirm equipment response | 6 months | — | Fan On then Auto (blower starts/stops), Heat call 1 F above room (soft click, System On), Cool call below room (blower + cold air; allow the 5-minute delay if setpoint flashes). Farber recommended pre-season, both stats. |
Troubleshooting
No heat, no cool, no fan
- Check the coach breaker/fuse for the HVAC circuit and reset/replace.
- Confirm the equipment power switch is ON.
- Reseat the blower compartment door - the door safety switch kills everything when the panel is loose.
- Tighten thermostat and equipment wire connections.
- Check/replace the stat batteries.
No heat (cool and fan OK)
- Relight the pilot if the auxiliary furnace has one.
- Set SYSTEM to Heat and raise the setpoint above room temperature; listen for the stat's soft relay click within a few seconds.
- No click: reset the stat (batteries out 2 minutes); still no click, replace the thermostat.
- Click but no heat: the furnace is in lockout or needs service - fault is downstream of the stat.
No cool (heat and fan OK)
- Set SYSTEM to Cool and drop the setpoint below room temperature; expect the click, allowing up to 5 minutes if compressor lockout is enabled (setpoint flashes).
- No click after the delay: reset, then replace the stat if unchanged.
- Click but no cooling: condemn the cooling equipment side, and read any Comfort Alert flash code showing with Call For Service.
Heat, cool, or fan runs constantly
- Check FAN isn't simply set to On.
- Inspect every stat terminal for shorted/touching strands - no bare wire beyond the terminal block.
- Reset the thermostat (batteries out 2 minutes).
- If equipment tests fine driven manually, replace the thermostat.
Keypad locked / staff cannot adjust, or lockout code forgotten
- Farber stats are intentionally locked: Menu, hold Installer Config, enter code 150, press up to unlock.
- Code lost or changed: press and hold the Menu key about 20 seconds to force-unlock.
- Temperature Limit flashing when adjusting means the setpoint hit the configured limit stops (items 24/25), not a lock fault.
- After service, relock (item 26 = L, item 27 = 150) and leave SYSTEM in Auto.
Blank or erratic display
- Static or a voltage spike: pull the stat off the wall plate, remove batteries for 2 minutes, reinstall.
- Replace batteries if the level icon shows low.
- If reset does not restore normal operation, replace the thermostat.
- After any reset, re-run the Farber standard configuration - defaults will have returned (programs/week back to 7, lockout off).
Call For Service flashing (heat pump / Comfort Alert systems)
- Count the flash cadence and match the Comfort Alert code: 1 long run, 2 pressure trip, 3 short cycling, 4 locked rotor, 5 open circuit, 6 open start, 7 open run, 8 welded contactor, 9 low voltage.
- On HP1 systems, indoor temperature falling below 45 F auto-switches to auxiliary heat and flags Call For Service - press any key to retry the heat pump.
- The code identifies an equipment fault, not a thermostat fault; dispatch on the compressor/outdoor unit.
Service parts reference
| Part number | Description | Type |
|---|---|---|
| 1F97-1277 | White-Rodgers Blue universal touchscreen thermostat, single stage / HP1 | repair |
| AA-ALK | AA alkaline batteries (2 per thermostat) | consumable |
| F145-1328 | Wired remote temperature sensor, indoor | repair |
| F145-1378 | Wired remote temperature sensor, outdoor (enables dual-fuel changeover by outdoor temperature) | repair |
Based on: Emerson 1F97-1277 Installation and Operating Instructions (37-7388001) + Farber internal 'Emerson Mammo Room Thermostat Configuration' setup sheet. This guide is an original work; always confirm procedures against your unit's build record and the manufacturer's current documentation.