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Keedian operations · Standard procedure

PHD — Thermostat Swaps, Setpoints, and Modes.

Troubleshoot PHD thermostats: locate the device, run a swap test for blank screens, adjust setpoints within corporate lockout limits, change operating mode (heat / cool / auto / EHEAT), and escalate via the 10-step hardware checklist when in doubt.

01 Detail

Trigger, action plan, and escalation criteria.

ad_hoc_client Client: PHD hvac refrigeration medium managed tier AI: hybrid
Value drivers
Customer experience Avoided truck rolls
Preconditions
Site is identified; replacement tstat of the same model available for the swap test when possible.
Human role
BSS-level technician locates the tstat, runs the swap test, captures readings, and either resolves on-site or escalates to T2 / HVAC vendor.
Action plan
(1) Locate the thermostat — some sites have tstats in associated zones, others all in the office area; if unsure, call the PHD support line (number redacted — see internal support directory; customer extension and technician extension differ). (2) If a screen is blank, run the swap test: pull the front plate of the blank tstat and a displaying tstat of the same model; cross-mount and observe — if the previously-blank tstat lights up, the original spot has a 24V power issue (route to HVAC); if it stays blank on a known-good back plate, the tstat itself is bad (route to replacement). (3) Adjust setpoints with the up/down arrows; respect the 3-degree heat/cool separation and corporate lockout limits (often ±2°F). (4) Change mode (OFF / HEATING / COOLING / AUTO; EHEAT only on heat-pump systems with a compressor failure). (5) Fan: AUTO (default), FAN ON (manual), or Cycle if installer-enabled. (6) Use the on-screen status indicators (SYS OFF / SYS MOT / HEAT ON / COOL ON / HEAT MRT / COOL MRT / 2nd Stg / Aux Heat / EHEAT / Home / Away / Alert) to read system state before escalating. (7) If symptoms persist, work the 10-step hardware troubleshooting list; document outcomes in Salesforce; mirror the notes into the platform ticket.
Author
David Dillard
Tools
Thermostat (PHD-standard) Salesforce Keedian Platform Ticket PHD support phone (number in internal directory)
Roles
BSS — Refrigeration team

Purpose

Ensure PHD thermostat troubleshooting (swap tests, setpoint adjustments, mode changes) is completed efficiently and consistently.

Scope

All BSS levels within the refrigeration team.

Procedure

Locate the Thermostat
  • Some sites have tstats in associated zones; others all in the office area.
  • Support: phone number redacted (see internal directory); separate extensions exist for customers and technicians.
1. Thermostat Swap Test
  • Run when a tstat has a blank display and another tstat of the same model is present with a working display.
  • Pull the front plate of the blank tstat and the front plate of a displaying tstat; cross-mount each on the other's back plate.
  • If the previously-blank tstat lights up on the new back plate and the displaying one stops displaying, the original location is not getting 24V (route to HVAC).
  • If the previously-blank stays blank on the good back plate while the displaying continues to display on the blank back plate, the tstat itself is bad (contact for replacement).
2. Changing Thermostat Setpoints
  • Press Up or Down to enter the setpoint screen; choose temperature (1° at a time); press Done.
  • If System Mode is OFF, the buttons take you to System Mode first — pick a mode before adjusting setpoints.
  • Setpoint push: cooling and heating maintain a 3°F separation; lowering cool pushes heat, raising heat pushes cool.
  • Corporate offices often impose ±2°F lockout limits — contact us to verify and arrange temporary overrides.
3. Changing Thermostat Operating Mode (Heat/Cool)
  • Press Mode; use Up/Down to select OFF / HEATING / COOLING / AUTO; press Done.
  • EHEAT (Emergency Heat) only on Heat Pump systems with a compressor failure — disables compressor output to prevent damage.
4. Thermostat Fan Mode
  • AUTO FAN (HVAC controls); FAN ON (manual until changed); Cycle (installer-enabled fresh-air ventilation).
5. System Status Indicators
  • SYS OFF / SYS MOT (Minimum Off Time) / HEAT ON / COOL ON / HEAT MRT (Minimum Run Time) / COOL MRT.
  • Staging: 2nd Stg, Aux Heat; Heat Pump only: EHEAT.
  • Home/Away display; Alert text for filter or maintenance timer.

Quality assurance

  • Confirm the swap-test result clearly identifies whether the issue is power-side (24V) or the tstat itself.
  • Confirm setpoints respect the 3°F heat/cool separation and any corporate lockout.
  • Confirm mode and fan-mode changes are intentional and recorded.

Troubleshooting

Tstat screen has no power.
Solution. Try a known-good tstat on the same spot; try the suspect tstat on a known-good spot. Use the 10-step list (yes-yes / yes-no / no-yes / no-no) to route to T2 replacement or HVAC investigation.
Screen is on but unit is not working properly.
Solution. Check if the tstat is making calls; verify voltage on the cooling/heating wires; if not, swap tstats.
Wrong control mapping.
Solution. Confirm whether this tstat controls another spot's unit and whether another tstat controls this unit; route to T2 or HVAC accordingly.

Documentation & reporting

  • Record notes in Salesforce; resolve or escalate the ticket when complete.
  • Mirror the same notes into a ticket in the Keedian platform.

Attachments

pdf
PHD - TSTAT (Swaps, Setpoints, and Modes).pdf
Source SOP — swap test, setpoint mechanics with lockout limits, mode/fan reference, system status indicators, 10-step hardware checklist.

Revision history

VersionDateAuthorChanges
1.0 03/01/2026 David Dillard Initial draft.