New Installation Not Working Quite Right

I've just installed the 'Tado V3+ (Black Edition) Wireless Heating & Hot Water Smart Thermostat Starter Kit', replacing the existing British Gas MODEL UP2 Controller/Programmer, and Honeywell DT90E (wired) room Thermostat, on a Baxi 600 boiler feeding a Y plan system.

The above pic shows the wiring (which has been independently checked), the wires from the removed B.G.UP2 remounted into the terminal strip feeds the Tado programmer.

The install was OK, and the wireless programmer and wireless thermostat successfully talk to each other.


Scenario (1)

Before 8:00 if the room temp is below 18℃, the thermostat triggers the programmer and the CH LED lights up (on the programmer ) but the central heating doesn’t come on until the HW is triggered at the set time of 8:00am. 

From this point everything behaves as it should until the HW timer goes to off, and again, if the CH is triggered by the room Thermostat the LED lights but no CH. This state can be over ridden by turning the HW on from the app or the programmer or Boost Heating function. 

Scenario (2)

During the programmed CH/HW ‘on’ timing block, when the room reaches the preset temp, the thermostat informs the programmer, the CH Led extinguishes, the HW LED remains on but the boiler goes off. If the temp in the living room drops the boiler is successfully relit because the HW LED is still lit. So I'm guessing that at this time the Hot water in the Cylinder must be at temp allowing the boiler to switch off but why does the LED remain on?

Thoughts Please.

Best Answer

  • johnnyp78
    johnnyp78 ✭✭✭
    Answer ✓
    Have you got it set for a gravity fed system rather than s/y plan? Look at section 6


  • No I did not use that setting as I wasn't sure what gravity fed meant. Is it refering to how the cold water is fed into the system ie from Cold water tank in the attic or somrthing else?

  • OK johnnyp78 just looked up Gravity fed Systems and yes ours most certainly is. Thanks for the advice and I'll configure it up tomorrow and post the result.

  • When I setup my system nearly a year ago, it was set up as a Gravity fed system, which meant my heating and hot water were coming on at the same time. I contacted tado support, they made a change on their side and it's been working fine since.

  • Having reconfigured the system last night the CH came on without the HW coming on. Success. Before the Timed block (CH and HW) ended, the CH having reached temp, switched off the programmer LED and boiler, but HW LED remained on even thought the boiler was off. Had plenty of hot water so not altogether sure if there is any thing wrong. Thank you both for your help.