# Replace thermostat with rasberry pi and Solid state relay

I want to replace my thermostat with raspberry pi board. I have already connected solid state relay to rasberry pi and it works just fine. The only part left to do is to connect solid state relay to the thermostat. I have an idea how to do that but before actually connecting anything I want to ask your advice if I am doing it right. My solid state relay looks like this

(source: asia.ru)

And the diagram on the thermostat looks like this

I have 4 cables

Blue - N
Red - L
Call - yellow
and ground yellow/red


So I think I should connect Red(L - Red) to SSR contact 1(ac in) and CALL (yellow) to the SSR contact 2 (Load). Is that the right way to do ?

P.S. Its in UK so voltage is 220V therefore I want to be extremely careful

• If you were being really careful, you'd replace your thermostat with a thermostat! – Scott Seidman Nov 13 '13 at 22:28
• Does anyone know what "CALL" means in this context? Is it "Call for heating" (or cooling for an air-con)? – Transistor Aug 21 '19 at 6:24