Thermotech Tt91 Manual Hot [work] May 2026

The TT-91 uses a front keypad to adjust process variables (PV) and set values (SV). Set Temperature (SV): key to enter the modification mode. Use the arrows to adjust the target temperature. Save Settings: key again to confirm and save the new value. Timer Control:

How to Auto-Tune: Press and hold the UP arrow key for several seconds until the display flashes "tUnE". thermotech tt91 manual hot

Step 2: Setting the Schedule

• Set the desired temperature and time schedule for each day of the week.
• Use the Prog button to save changes.

This guide covers the critical aspects of the "hot" side of the system—specifically the domestic hot water and heating controls. The TT-91 uses a front keypad to adjust

Step 2: Feel the wall behind the thermostat.

If the drywall is warm, the problem is in the wiring. Turn off HVAC power at the breaker. Remove the TT91 faceplate. Inspect the terminal screws (R, W, Y, G, C). Look for: Set the desired temperature and time schedule for