wires where marked when i removed it but on removing it have found out i have 2 reds ,2 blacks .and 2 earths only three terminals on homexpert on sunvic 2 red wires had there own terminals the 2 blacks shared one termina the earth i know what to do withl
i want to replace a sunvic tlx 2259 with a homexpert thr840duk but cant work out the wiering i have two red one black and the earth can some one help me with how to wire this up i am running it on oil heating thanks