Programmer wiring.

[Rocketmen]

Just bought a new digital programmer to replace old mechanical one. New one (Drayton LP241) fitted onto old back (Landis & Gyr). All works fine, but the instructions state that I should be able to get the CH to operate independently from the HW. I can only get the CH to work when the HW is on. Looking at the wiring, only pin 3 and 4 are used. Pin 1 has a linked live from the L terminal.

Any ideas on how I can wire this up for separate CH & HW?

Thanks Guys.

 

[seco services]

have you set the link on the back from G to P ?

 

[pompeyal]

Why should you want the CH on without the HW, it seems strange to say this in the instructions. All the systems I have fitted have had perminant HW and switchable CH. The HW regulates itself with the thermostats.

 

[Whitespirit66]

Why should you want the CH on without the HW, it seems strange to say this in the instructions. All the systems I have fitted have had perminant HW and switchable CH. The HW regulates itself with the thermostats.

I don't understand your reasoning. Many people like to have their HW on for set periods maybe twice a day.

Also, what if the OP hasn't got a cylinder stat? Not everone has.

 

[PEDANTICVINDICTIVEMAN]

So what system you got, gravity HW pumped heating, S plan C plan Y plan W plan ?

 

[weareleeds]

What system have you got? on an s plan 3 is dhw on 4 is c/htg on terminal 1 is a hot water off terminal which is only used on y plan so shouldn't be linked to live

 

[Rocketmen]

Thanks for your thoughts and questions.

The link on the back was already set to P.

I would like to set my timer to get HW just first thing in the morning. However need CH on all day for disabled wife.

I have a gravity fed pumped CH system. I don't understand your questions about the type of plan.

I would really like to run the CH without HW if poss.

Many thanks.

 

[hansthebear]

not possible without converting to a "fully pumped" system

 

[twgas]

You don't say which model of timer you used to have, but the link you mention is normally fitted to a single channel timeswitch, although the backplate is the same as most programmers the wiring is diferent.

 

[D_Hailsham]

I have a gravity fed pumped CH system. I don't understand your questions about the type of plan.

Do you have any motorized valves - usually near the pump or HW cylinder?

View media item 5946 View media item 11762
and do you have a themostat on the side of the HW cylinder?

View media item 10596

 

[Rocketmen]

My programmer is a Drayton lifestyle LP241.

I have a tank thermostat and a motorised 3 post valve, The actuator is a Honeywell V4073A1039 Sundial Y plan.

Thanks

 

[simond]

If you have a Y plan, the progammer will be using outputs 1,3,4.

If you have no separate cable from terminal 1 to the wiring centre, it will not operate the 3 port valve correctly.

Its not all unusual to find these wired incorrectly from new.......

 

[Rocketmen]

Thanks Simon, I only have L,N & pins 3&4 wired up. There is no spare cables except for a yellow from a 4 core which is joined to the live feed for the boiler in the box behind the programmer.

 

[Whitespirit66]

This link explains the wiring your wiring, and how the programmer should be wired up. Note that it is for boilers with pump overun, where the pump is wired through the boiler. Your may be slightly different.

The grey wire from the motorised valve is wired to the hw off terminal on the programmer. Have you got grey, and where is it wired to?

http://octaveblue.co.uk/c_heating/ch_only.htm

 

[Rocketmen]

Thanks Whitespirit66, the grey wire from the motorised valve links to the "earth" wire to the tank stat. There is no other wire taken from that connection.

Am I doomed?