Boiler staying on

Hi all

I have a Valiant boiler and Tado with smart thermostatic valve on all rads except bathroom towel rail.

When my system was first install I was informed it is best not to put thermostatic valves on every radiator but keep one clear which is the bathroom towel rail.

Since installing the Tado system I have noticed that when the system is shut down the towel rail stays on 24/7, it never did this with my old controller.

I do intend fitting a TRV to the towel rail but could someone tell me why the boiler is not completely shutting down when it is meant to be off?

Thanks for any advice


  • johnnyp78
    johnnyp78 ✭✭✭
    Are you sure your towel rail isn’t electric as well? Have you checked that the boiler is staying on?
  • No good idea about the ‘call for heat’. However, your heating boiler will probably overrun?
    The heating system should have a ‘bypass’ to cool the boiler water during overrun. That could be a) a bypass in the boiler, b) an external bypass device on the heating/HW pipe work, c) an uncontrolled radiator such as in the hall or a towel rail.
    Don’t shut down a bypass without knowing the heating system design.
    If in doubt, contact a professional.