Pros, Join Our TradeMaster Program!
D-508F digital non-programmable heat only thermostat is designed to control either ambient(air) temperature (A Mode) or floor temperature (F Mode) or a combination of ambient temperature with floor temperature limits(AF Mode). An auxiliary remote sensor is provided to measure slab temperature in order to control the floor temperature(within maximum and minimum limits in AF Mode). It can also be used for sensing the outdoor temperature in A Mode.

  • Easy-to-Read Digital Multi-Display with backlit which provides constant readout of two sensor temperatures(eg. ambient and floor) and setpoint simultaneously, functional status and control settings.
  • Three temperature control modes:
    • A Mode: controls ambient temperature
    • F Mode: controls floor temperature. Also displays current ambient temperature.
    • AF Mode: controls the ambient temperature and maintains the floor temperature within the desired minimum limit for floor warming and maximum limit for protecting floor coverings. Also, displays current floor temperature.
  • QuickSet feature allows instant setpoint adjustment without entering the SETTING mode
  • Contemporary design
  • Easy installation and setup
  • Selectable display in °F or °C
  • On/Off switch to shut off relay output or shutdown the thermostat at end of heating season for added security
  • EEPROM memory retains control settings in the event of a power failure
  • Lockout mode to prevent tempering by unauthorized personnel
  • Sensor failure and out of range indications
  • One stage heating application
  • Backlit option: Auto (60 sec.)/OFF/ON
  • Supplied with P-01 floor sensor
  • Battery free
  • RoHS (Restriction of Hazardous Substances) compliant means this thermostat is eco-friendly
Read more
Manuals (2)
Product Type:
Heat Only
Extended 3 Year
User Interface:
Push Button
Power Supply:
24 VAC
On/Off Switch
Speak with a real person who will go out of their way to help!
Open Now:
Monday – Thursday
8am–7:45pm ET
9am–7:45pm ET

3 Videos

    6 Product Reviews

    Product Q&A

    Add-on Item

    This item is cost-prohibitive to ship on its own but is available to ship with orders over $200.

    Why don't we show the price of this item?

    We try to always offer you the lowest prices possible, but some manufacturers require that we only show these low prices once you take further action.

    To see the price, simply add the item to your cart or sign in.