Inside the control box, there are typically DIP switches or Jumpers that allow the installer to configure the system to the specific spa environment:
4. Programming
To conclude, let’s address the red flag in your search term. If your thermotech tt91 manual hot search was prompted because the unit is burning to the touch:
Ticket Subject: Thermotech TT91 Manual - Hot / Heating Mode Issue
User Question: "I need the thermotech tt91 manual. It is getting too hot / How do I set it to hot?"
AI Support Answer:
Hi there. It sounds like you are trying to configure your Thermotech TT91 for Heating (Hot) mode.
To switch to HOT mode:
If the room is too HOT (unit won't stop heating):
Manual Download:
We do not host the PDF directly due to copyright, but search for "Thermotech TT91 Installation Manual v1.4" on Google. Look for the result that ends in .pdf from a HVAC supply store.
Need a quick fix? Turn the setpoint down to 10°C (50°F). If the heater still produces extreme hot air, bypass the thermostat to test the valve/heater directly.
If your TT91 has a heat pump, the manual specifies that the O/B terminal must be configured for energizing in cooling (O) or heating (B).