Panel heaters with no power

[captaincaveman]

Can anyone perhaps give me some direction here as i don't have too much experience with heating and this is baffling me somewhat :rolleyes2: .

I've got 4 panel heaters, two of which are fan assisted. The latter two which are in the lounge & dining room can't be switched off. the other two, in the bedroom & hall won't switch on.
The heaters run from separate mcb's via a 230v contactor to switches next to the fans.
The heaters in the lounge & dining room also run from separate mcb's labelled 'fans' which go via fused spurs next to these heaters.
The contactor switch, which i can't locate the source for, assumingly runs from the fire system?

When i first looked at the contactor i was getting supply voltage but no load voltage from it. After replacing the contactor I am now getting 230v from the load side, but only for the bedroom & hall circuits. The lounge/dining room loads are 50v

The fan fused switches have power to them but none of the heater switches are receiving power (even though 230v is leaving the contactor/ccu for two of them!)

Below is a diagram of my interpretation of the set-up. (note. the previous owner was evicted so i'm not ruling out sabotage lol)

 

[SYKRAPS]

Are you sure that they are not storage heaters that are powered from an off peak metering system?

 

[john999uk]

From your diagram your voltages seem very strange. Looks like only 2 poles of contactor are working. Can you remove contactor and do a continuity test on all poles with it energised?
If the room switches are open then from your picy and the voltages it looks to be the contactor.
I guess that in the event of a fire the fire alarm disconnects the heaters, seems like a good idea if a bit unusual.

 

[captaincaveman]

The strangest thing is that with the two that have current leaving the contactor don't have current arriving at the switches/heaters

p.s. Cheers for replies guys, all taken into account & appreciated

 

[malcolmsanford]

CC seems strange that the 2 units causing you this problem are the 2 units that have a separate supply to the fans? That to me would start me thinking is there something amiss.

To prove contactor is ok just swap either lounge/dinning with hall/bed and see what happens, I have a sneaky feeling you may just move that 50 volt over to another contact.

I have a sneaky feeling that the circuit is wired wrongly, and you are serising things up here. It is a pretty simple set up and I personally would take everything apart, start belling things out and see where you go

 

[Clive P]

Hi,

As Malcolm says this is a simple set up.
1. Are you sure the Contactor is 4 pole , and not 2 Pole ( the other 2 being auxiliaries )and they have been overloaded ?
2. Have you checked the FCU's are connected to the fans correctly?

Regards.

 

[captaincaveman]

Alas i ran out of time and am waiting for the thumbs up to go back. The sooner the better as far as I'm concerned as i get frustrated when not able to solve a problem like this