Remeha iSense not compatible with Tado? (2024)

olitee

Hi!
I have just ordered a whole Tado Kit and installed it.

Old setup:
- boiler = Remeha Calenta
- Thermostat = Remeha iSense (Wired)

I have replaced the thermostat with a wired Tado smart thermostat (connected 2 cables to + and - following instructions).

Now things aren't working. If I request a high temperature, the boiler thinks it is giving hot water, but the radiators are cold and the tapwater is also cold.
I was wondering if there are still compatibility issues since I read in a different thread that "Remeha iSense not compatible with Tado?"

Thanks for any insight!

policywonk

Hi. @samd 's comments made me grin. My thoughts:
A basic central heating pump that does not self regulate is, in my experience, a source of waste. I really don't believe a boiler, even one that doesn't self regulate, needs three rads open to remain sane.
If it really is a boiler without its own throttle control then you should talk to your plumber about fitting a bypass valve and/ or a pump which maintains consistent differential pressure.

samd

You said following instructions. Were those instructions from tado please?

olitee

Hi!
Yes I followed the guide in the app
(that recommended connecting the wires to the OT (Opentherm) + and - in the Tado thermostat.

samd

Not quite what I asked methinks. Did you, pre-installation*, contact tado and ask for instructions specific for the equipment you own currently please?

*Usually pre-purchase.

olitee

Hi!
No I didn't.

BTW there was an issue with the boiler - the pump was stuck. Now fixed, and it seems to work.
But here's a new thing: the plumber said if the boiler is running, it needs at least 3 radiators to be open in the house. I wonder how to make sure this happens with the Tado system - can't think of a way to guarantee that (apart from leaving 2 radiators with basic Thermostatic valves and always open)

samd

Do you not think the plumber's advice needs checking? Even with your idea of 2 rads with basic valves, they would need to be permanently fully open at stupid cost and over heating the rooms chosen. Maybe I have missed the point?

wateroakley

When using thermostatic valves that restrict hydraulic flow the system probably requires an external bypass ? Best to ask the plumber to check the boiler installation manual.

olitee

Thank you @policywonk, @samd and @wateroakley for the useful insights!