On 26/05/2020 19:39, John Smith wrote:
On 2020-05-26 10:41:59 +0000, John Rumm said:

i presume the system needs a drain down to do the valve but it's just
a couple of large screw nuts.

Yup in principle - although it does depend where in the system the
valve is, as to how much of a drain it will need (valves in a loft for
example can often be change with only a partial drain down).

Thanks John. What do you think of this - it's the same Danfoss valve and
as the pipework is at the back under the stairs it may be easier just to
change the spindle but looks hairy without draining down. I guess easy
to do if drained down and guards against disturbing pipes as the
cylinder is very near.

https://youtu.be/1vYCkGtR-l8

I have never worked on a Danfoss valve, so that was an interesting vid.

It looks doable, and even if you decide to bail out and do a full drain
down mid process, you should be able to plug the valve base with
something to keep the water in the for duration. Easier than replacing
the whole valve body anyway.

(my plumbing kit has a set of conical rubber bungs for just such
eventualities. Also very useful for plugging the feed and expansion
pipes on vented HW systems or vented CH header tanks to keep most of the
water trapped in them)


--
Cheers,

John.

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