I would expect that of someone was suggesting the valve were "stuck",
they would not be talking about the manual leaver. In these situations
is more common to take the motor head right off, and see if the spindle
sticking out of the top of the wet bit will turn (with pliers and
lubrication etc). If its seized, then replacement of the wet part
No, quite, it was just the possibility / chance I was talking about.
Ah, so the manual lever isn't actually a manual lever but a manually
operated switch to override the timer / controller electrical input?
The issues seemed to be (from what I was overhearing from the
plumbers) was the possibility that the 'new valve' they had fitted
previously (days / weeks before) wasn't working properly but I also
heard them saying to the householder that they 'weren't electricians'
so I questioned (in my head) just how much they knew about any of it?
Maybe they were just plumbers and what my friends needed was 'Heating
Time will tell etc. ;-)
Cheers, T i m
No, its a leaver that moves the gearbox mechanism through some of its
normal travel - usually enough to move the valve position, but not
always enough to bump into the micro switches at the end of the normal
motorised travel (and which would be required to fire the boiler with
the conventional wiring plan).
Its possible for the gearbox or motor to fail, or simply be unable to
exert enough force to turn the spindle (either at all, or far enough).
In many cases, adding some lubrication to the spindle and working it
back and forth with pliers etc will free it enough to work normally after.
(We have that now and again with the electric curtains where the track
gets damp and the current limit trips before the max travel).
Yeah, been there and done that with enough stuff over my life, the
last being a mates mates motorcycle rear drum brake lever that was
actually seizing up. He was going to just spray it with WD40 (that may
have worked, especially short time) but I recommended we 'do it
properly'. So we removed the rear wheel, stripped the brake drum,
cleaned and *re-greased* the lever and replaced the missing O ring /
Probably not so easy or appropriate to replicate on a valve full of
water though. ;-(
Cheers, T i m
On Mon, 13 Nov 2017 16:46:26 +0000, John Rumm wrote:
When I was looking to fix the problem of the 1st floor radiators warming
up when hot water only was called for some two or three years ago, I was
initially looking at prices for a complete 3 port Honeywell valve
assembly around the 150 quid mark.
After a bit of researching, I discovered that I could retain the
expensive brass part of the valve body by upgrading the all in one motor/
valve plate to a modern (post 1982!) two part motor and valve plate that
would allow any future motor head problems to be fixed without the need
for a drain down. I got the valve plate from, I think, my local Plumb
Centre and a modern detachable motor head from Tool Station in the end
for just under 70 quid all in.
One thing that tripped me up was testing the motor head in isolation
from the valve plate spindle which revealed a slipping gears problem. It
was only *after* experiencing the same "fault" with the replacement from
Tool Station that it finally dawned on me that it was the lack of support
to the final sector cog normally provided by the valve spindle and the
only thing that had been at fault was my testing technique.
I felt so bad about returning a fully functioning part as being faulty
that I went back to Tool Station, with the second motor unit in hand,
just to apologise and explain my mistake to the very accommodating sales
member who had dealt with my returned "faulty" motor head just so he
could know that there hadn't been anything wrong with the original part
in the first place.
Compared to Screwfix, the Tool Station counter staff are a joy to deal
with so I felt I owed them the courtesy of an apology. Besides which, TS
prices are generally lower than SF's prices so yet another reason to show
 That was my first port of call because I had hopes of being able to
cannibalise the rubber ball to replace the hardened and misshapen one in
the original unit which had been the root cause of the problem. Only then
did it become clear that I'd need to buy yet another part, a compatible
motor head unit before I could complete the repair.
I think the valve plate was around 23 quid in all with, to my surprise,
Tool Station proving to be the cheapest source of a compatible motor head
at a mere 45 quid or so compared to on line sources quoting 65 quid or
And, whilst I remember, the only other expense involved was the 4 quid
spent on the purchase of a 39mm AF open ended chrome vanadium spanner
from a second hand tool store my missus had insisted was no longer in
business (such insistence resulting in a fruitless search via a 22 mile
round trip to the next town's market) to grip the flats of the Honeywell
3 port valve body. Thanks to the upgrade to a modern two piece motor head/
valve plate, a tool I may never use again in anger to repair the central
heating system in my lifetime.
Thank goodness it was only a mere 4 quid! In all honesty, I think it's
more likely to see service as a defensive weapon kept under the bed for
use against night time intruders than as a plumbing tool.
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