dibekem
New Member
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
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
