Recent content by Muttley3

Update. I noticed changing the LP/ZP Relay setting from ‘No connect’ to ‘Circulation’ seemd to have reverted itself so changed it again and a few hours later Cylinder temp. current is 61 without the immersion on. :) So the problem seems to have been caused by corrupted system configuration...

I have a Vaillant Ecotec 637plus system boiler feeding a Unistor unvented cylinder for HW and radiators in just one heating zone controlled by a VRC470F, weather compensation sensor, VR61 control box and VR10 cylinder thermostat. All installed about seven years ago. Two or three months ago it...