denfoss randall SET2 replacement problems

[Dibekem]

Hi guys.

I have a randall set 2 timer switch which has gone faulty.

Im not a plumber but the plumber found out that this was the fault on our heating system. So he said just need to change this timer.

Im currently doing my NVQ in electrical installations so I said I can do that.

For a temporary solution he did some connections to bypass the timer and just control the heating/hot water by the the boiler manually.

So I got the new timer switch today which is a danfoss FP975. This should be the replacement for the set 2 timer that I had.

Today I opened the old timer and well I'm a bit confused. I can see he did some temp connections but not sure where. I wrote everything down so I can put it back if it all goes wrong.

The connections are as follows.

N-neutral , L- live,
1(DHW ON)- hot water cable ,
2(DHW COM)- link to L ,
3(DHW OFF)- N\C ,
4(HTG ON)- Heating cable ,
5(HTG COM)- N\C,
6(HTG OFF)- N\C.

So there was this link with earth cable which I think is the temp connection. This was on the top of the other connections.

1 was link to 2 and 4 in a terminal block. So I read that the live should be connected to 2 and 5. So I did that. Also removed the temporary connection. When I switch it on I had hot water when I pressed the hot water but the heating did not worked when I pressed the heating button.

Just looking at the set2 wiring diagram that suggest to connect 1 to 5. If anyone could help would be greatly appreciated! Thanks

 

[Dibekem]

[COLOR=rgba(0, 0, 0, 0.701961)]Here is little update. It's kinder working now but definitely not how it should be. [/COLOR][COLOR=rgba(0, 0, 0, 0.701961)]
The heating and hot water controlled by a HSA 3 port valve. The boiler is Potterton Prima F 30 F.

1, when I press the hot water button the hot water comes on.

2, when I press the heating button the system starts a little then stops and there is no heating.

3, when I have both of them on they both working (I can feel the hot water and heating pipes getting really hot)

I thought it might help to tell you this. ��
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[jonnyswamp]

Can you not ring the plumber back up and ask him to come and show you?

 

[tamz]

Good experience this. When you figure it out you'll know what to look for next time.

This will give you a clue (same wiring)
http://www.honeywelluk.com/Documents/Full-Install/pdf/1083.pdf

The commons on the programmer need to be linked to live btw