Heating programmer help please....?

petedavids69 · Jan 22, 2024

Hi Guys
Changing my heating/water programmer and im stuck on the wiring ive gone from a danfoss to a Drayton and the wiring description is different ive had a go at what I think is correct but now when the heating is on and hot water off the hot water is still calling, and when I have just hot water on the heating comes on also. Ive attached a couple of pics of the old one and new one can anyone tell me which numbers on old ones go where on new one.
Thanks in advance..
Peter.

DefyG · Jan 22, 2024

L & N are obvious.
Blue 3 Old to 1 New.
Yellow 1 Old to 3 New
Red 4 Old to 4 New
Brown 5 Old to L New
Links L-2-5 Not Required

Presumably fully pumped?

petedavids69 · Jan 22, 2024

DefyG said:
L & N are obvious.
Blue 3 Old to 1 New.
Yellow 1 Old to 3 New
Red 4 Old to 4 New
Brown 5 Old to L New
Links L-2-5 Not Required

Presumably fully pumped?

Thank you so much! how do you mean fully pumped? it has a pump up in airing cupboard which works off the wiring centre in there.

DefyG · Jan 22, 2024

There is a red 'jumper link' in the new programmer set for fully pumped which is fine as the wiring is consistent with a fully pumped system.

petedavids69 · Jan 22, 2024

DefyG said:
There is a red 'jumper link' in the new programmer set for fully pumped which is fine as the wiring is consistent with a fully pumped system.

Ah ok I was going to ask about the red jumper, so that stays where it is then? the system has 2 zone valves and a pump.

freddo · Jan 22, 2024

Yes, gravity mode is not used much now, (thank goodness) it was for old systems where the hot water from the boiler convection circulates to the hot water cylinder through large pipes, without the need for a pump. The pump only being used for pushing the water through the radiators. This is not an efficient system design and many systems rely on the boiler thermostat to set the hot water temperature.

All the link does in gravity mode is ensure the hot water relay is switched on all the time the heating relay is on, or the heating pump would run without the boiler being switched on.

In fully pumped mode the hot water and heating relays operate independently.