Heating boiler was wired into this contactor box in a garage (not huge house).
Boiler cable comes out the bottom, but WHY such a complcated setup domestically??
Contactor wiring
- Thread starter Mike2007
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Heating boiler was wired into this contactor box in a garage (not huge house).
Boiler cable comes out the bottom, but WHY such a complcated setup domestically??
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It's 2 relays (not contactors) in a box, not exactly complicated.
Probably used to switch 2 bits of equipment by a single output or a single bit of equipment from 2 sources,, or something that takes more current than the switching output can handle or something else...
There, I think that's covered why
Probably used to switch 2 bits of equipment by a single output or a single bit of equipment from 2 sources,, or something that takes more current than the switching output can handle or something else...
There, I think that's covered why
Does this suggest an electrical heating element somewhere. Something a 5amp control unit can't handle?It's 2 relays (not contactors) in a box, not exactly complicated.
Probably used to switch 2 bits of equipment by a single output or a single bit of equipment from 2 sources,, or something that takes more current than the switching output can handle or something else...
There, I think that's covered why
I have seen this (either/or) wiring on a house that has an electric shower plus an electric boiler. Too much load, so they switch from one to other but not both at same time.
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It looks to me like this is 2 devices controlling one boiler. Some arrangements of motorised valves require relays for correct operation.
Seem to recall, If you dont have a timer and use 2 switches one for Heating and one for Hot water, a set up like this is needed so it still fires up the boiler to heat the water even with the Heating off.
I quess locating the other end of the cable may give the answer
I quess locating the other end of the cable may give the answer
As an example I had 3 valves for: gravity hot water and 2 heating circuits.
With only one heating circuit the room stat could start the pump and open the valve, the valve could then start the boiler, as did the hot water valve.
However adding a third valve meant there were 2 room stats and a means of starting the pump from either or both had to be added. My solution was to make the room stats operate their valve and both heating valves operate a single 2 pole relay, one contact starting the pump, the other starting the boiler.
With only one heating circuit the room stat could start the pump and open the valve, the valve could then start the boiler, as did the hot water valve.
However adding a third valve meant there were 2 room stats and a means of starting the pump from either or both had to be added. My solution was to make the room stats operate their valve and both heating valves operate a single 2 pole relay, one contact starting the pump, the other starting the boiler.
So all this gubbins is to prevent unwanted feedback and starting of boiler or a pump over run requirement?
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Something like that but from a distance We can't tell exactly.
In this the SPST relays enable the boiler after one or both valves have opened and started the pump. The timer relays leave the valve(s) open and the pump running to keep circulating the water to cool the boiler after is shut down.
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