In article ,
"Dave West" writes:
We have a bedroom radiator that we occasionally want to turn right down. It
has 'tamper-proof' caps on the valves at each end. So I will replace one cap
with a new one that easily allows the turning of the valve.

Is it advisable to put the new cap on either the water incoming end or the
water outgoing end of the radiator?

That can mean it's the bypass loop for the system, so you
can't turn it down. You can reduce its output by partially or
fully covering it with towels or similar.

Otherwise, you will first have to show it isn't the bypass loop
for the system.

Is the system's thermostat in the same room? If so turn that down.
If that makes the rest of the house too cold, use the towel method
aa20s above.

BTW, doesn't matter which end the flow is controlled from.
Some early TRVs did care which way the water flows through them,
but I don't think any current ones do.

--
Andrew Gabriel
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