Is tank thermostat needed......

[wimmer]

My mum has a Rayburn oil-fired boiler for heating & hot water. Upon taking the cover off the main box in the airing cupboard, it appears that there is a red wire from the tank thermostat, not connected, (just a yellow wire connected). There is no hot water temp setting on the Rayburn, so should this red wire be connected? Thanks anyone.

 

[hotandcold1]

The oil rayburn is just a heat source so its either working or not if heating side is working then issue lies with the system. is it an s or y plan ( what motorised valves do you have?)

 

[wimmer]

Hi, the water in the tank gets hot, but there doesn't seem to anywhere to adjust what temp it gets to, apart from the tank thermostat, ( with the loose wire). BTW There are 2 motorised valves, (2 way), one on the HW and one on the CH pipes.

 

[hotandcold1]

Hi, the water in the tank gets hot, but there doesn't seem to anywhere to adjust what temp it gets to, apart from the tank thermostat, ( with the loose wire). BTW There are 2 motorised valves, (2 way), one on the HW and one on the CH pipes.

Cylinder stat like any switch requires minimum of two wires connected therefore it sounds like if the water is getting hot and only one wire to the cylinder stat the motorised valve has been overridden or incorrectly wired.
The Answer is yes you do need a cylinder stat wiring . Two wires from C & 1 on cylinder stat wired in parallel to timer live and Rayburn switch wire.

Hope this link helps

try this page www.rayburn-web.co.uk/raytech/chtg4.htm

 

[wimmer]

Looks like the theromstat wires go on 9 and 10 (where I think the loose red wire came from). Fingers crossed!
Thanks very much.

 

[zzzjim]

.................... has been overridden or incorrectly wired...........

This leaves a When and Why , is the stat still any good ?