Hi Guys - I have an old valliant vcw sine 18 t3 boiler. I bought a Heatmiser PRT thermostat today, hoping to replace an old mechanical Sunvic TLX2259 stat. Which had 4 wires connected - Red, Blue, Yellow & an earth.
I wired the Heatmiser using Red=Live Blue=Neutral and Yellow=A1/A2 but the heating would not come on. I tried both A1 & A2 but still no Joy.
After reading several posts i made sure the old Timer switch was set to constant
What am i doing wrong?
I wired the Heatmiser using Red=Live Blue=Neutral and Yellow=A1/A2 but the heating would not come on. I tried both A1 & A2 but still no Joy.
After reading several posts i made sure the old Timer switch was set to constant
What am i doing wrong?
