Honeywell Programmable Room Thermostat T4M 7 Day Modulating T4H310A3032

The Honeywell T4M is a wired 7-day programmable room thermostat designed to provide automatic time and temperature control of domestic heating systems. It is the modulating version of the T4 platform, so rather than simply switching the boiler on and off it varies heat output to hold the room closer to the set point. Part T4H310A3032 is listed by Honeywell under its residential products range and is intended for wall-mounted installation on a domestic system. Programming covers a full seven-day schedule, allowing different time and temperature settings for each day of the week.

• The display is blank, flickering or does not respond to button presses.
• Rooms sit below the set temperature, or overshoot it noticeably.
• The heating continues to run when there is no call for heat.
• The 7-day programme is lost or resets after a power interruption.
• The boiler short-cycles while the thermostat reading stays steady.

• Confirm the part number on the existing thermostat and the wiring arrangement at the wall plate.
• Check that the boiler accepts a modulating control signal; a boiler with switched-live demand only will not use the modulating output.
• Verify the appliance against the compatibility list below before ordering.
• Wiring work on the heating system should be carried out by a competent person.