Hi
Decided to replace the ageing Switchmaster 805 with the new Honeywell ST9400C (backlit screen - nice )
Well, Disconnected the Switchmaster, took note of the wiring - as follows
2 connections - 1 had 2 wires Black & Red (1)
1 had 3 wires - Blue, Yellow & Red (2).
yellow was wired to water off.
black was wired to heating off
red 1 was wired to heating on
red 2 was wired to water on
blue was wired to N.
OK
Fitted the Honeywell, wired it up as follows
Yellow to 1 - Water off
Black to 2 CH off
Red 2 to 3 Water on
Red 1 to 4 CH on
Blue to N
Wired in mains connection, slotted the programmer onto plate, it lit up and clock etc came on.
Problem is - can only get hot water if both water and heating are on, however the radiators don't warm up at all. The Honeywell looks like it is working ok, lights up etc but the system doesn't respond!
It worked fine before...Any ideas?
Colin
Decided to replace the ageing Switchmaster 805 with the new Honeywell ST9400C (backlit screen - nice )
Well, Disconnected the Switchmaster, took note of the wiring - as follows
2 connections - 1 had 2 wires Black & Red (1)
1 had 3 wires - Blue, Yellow & Red (2).
yellow was wired to water off.
black was wired to heating off
red 1 was wired to heating on
red 2 was wired to water on
blue was wired to N.
OK
Fitted the Honeywell, wired it up as follows
Yellow to 1 - Water off
Black to 2 CH off
Red 2 to 3 Water on
Red 1 to 4 CH on
Blue to N
Wired in mains connection, slotted the programmer onto plate, it lit up and clock etc came on.
Problem is - can only get hot water if both water and heating are on, however the radiators don't warm up at all. The Honeywell looks like it is working ok, lights up etc but the system doesn't respond!
It worked fine before...Any ideas?
Colin