Towel rail valve change - hot water circuit

15 Jan 2024
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United Kingdom

We have a conventional boiler - boiler, hot water cylinder, cold water tank and expansion /header tank (both in loft). The boiler has one motorised valve. I need to replace a leaking valve on a towel radiator - which only comes on when the hot water is switched on. I assume this is on the pipe run between the motorised valve and hot water cylinder. I don't know if the return from the tail goes back onto this pipe, or back into the radiator return loop, if that's makes sense.

I've drained down the radiators before without issue (drain point on radiator, stop valve on loft tank to stop the rads from re-filling), but what do I need to do to drain water from the hot water loop/stop the flow?

Boiler photo - hot water goes right of motorised valve.

Tank - left pipes don't have any stop valves. Right pipes at top (hot - hot tap water right?) don't really have any valves either.

Is it done in the same way as the central heating?



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The water that runs around your radiators is the same that runs through your cylinder coil and towel rad, and can be drained as you would if working on any other radiator.
Latch the mid position valve manually before draining.
Thanks! I was just editing to ask was it done in the same way -simples.

Latch the mid position? Is that move the metal slider (photo - on the left side of the MV) to the middle? Assume that stops any flow either to HW or Heat?
Yes ,move the lever and latch it into manual position.
That opens the valve to both ports ( mid position) so water can flow out of/ in through, both ports.
And isolate electric supply to heating system first.
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