I appreciate that this is a commonly discussed matter within this
newsgroup, but the specific question we want to address/resolve is not
one we can find the answer to here, so we thought we'd ask.

We have a Honeywell V4073A valve which seems to have died, so we've now
removed the powerhead, and successfully rotated the spindle on the
valve by about 10 degrees using a small adjustable wrench and minimal
force (we didn't know whether it might have seized - we do live in a
hard water area). As a consequence, we now have just HW (which is what
we want for now, we don't want the radiators on too - before removing
the powerhead, we could get HW + CH (not ideal in mid summer) by
forcing the manual lever over to manual with a large matchstick!).

Now, with the powerhead off, and the spindle manually rotated, we have
just HW. We now have to decide whether to a) buy a whole new valve and
drain the system b) buy a new powerhead and refit it on the valve
(perhaps only to find that this too burns out because the spindle
requires too much force for the motor?) or c) to just buy a new motor
(I believe the latter can be bought for between =A310-=A320 depending on
whether one buys a generic on from Screwfix, or a Honeywell original).

The old powerhead (still connected to the mains) is now resting in a
non conductive bowl on the airing cupboard floor, essentially to we
could check to see whether the motor's ever active. We have tried
selecting CH only with the thermostat turned up, but nothing ever stirs
in the powerhead (could be faulty/worn microswitches?). We have also
tried watching when the HW is selected, but nothing stirs (we reckoned
from the tech sheet that power may only flow when CH is called for). We
have tried both HW + CH too. Prima facie, it looks dead.

At this stage we just want some advice as to whether it is would be
wiser to go for an entirely new powerhead, or just the motor, and how
we might go about testing the integrity/functionality of the present
powerhead in order to decide. We'd also like some advice about how
easily the spindle, which sticks up out of the valve, *should* turn.
We've read elsewhere that it might turn with just "finger pressure",
however, without a torque wrench and some idea of what Newtons are
required, we don't know how much force is normal so don't know if the
valve may be stiff. This, no doubt is why one usually calls in the
professionals I guess!

Advice gratefully received.

In an earlier contribution to this discussion,
wrote:

I appreciate that this is a commonly discussed matter within this
newsgroup, but the specific question we want to address/resolve is not
one we can find the answer to here, so we thought we'd ask.

We have a Honeywell V4073A valve which seems to have died, so we've
now removed the powerhead, and successfully rotated the spindle on the
valve by about 10 degrees using a small adjustable wrench and minimal
force (we didn't know whether it might have seized - we do live in a
hard water area). As a consequence, we now have just HW (which is what
we want for now, we don't want the radiators on too - before removing
the powerhead, we could get HW + CH (not ideal in mid summer) by
forcing the manual lever over to manual with a large matchstick!).

Now, with the powerhead off, and the spindle manually rotated, we have
just HW. We now have to decide whether to a) buy a whole new valve and
drain the system b) buy a new powerhead and refit it on the valve
(perhaps only to find that this too burns out because the spindle
requires too much force for the motor?) or c) to just buy a new motor
(I believe the latter can be bought for between £10-£20 depending on
whether one buys a generic on from Screwfix, or a Honeywell original).

The old powerhead (still connected to the mains) is now resting in a
non conductive bowl on the airing cupboard floor, essentially to we
could check to see whether the motor's ever active. We have tried
selecting CH only with the thermostat turned up, but nothing ever
stirs in the powerhead (could be faulty/worn microswitches?). We have
also tried watching when the HW is selected, but nothing stirs (we
reckoned from the tech sheet that power may only flow when CH is
called for). We have tried both HW + CH too. Prima facie, it looks
dead.

At this stage we just want some advice as to whether it is would be
wiser to go for an entirely new powerhead, or just the motor, and how
we might go about testing the integrity/functionality of the present
powerhead in order to decide. We'd also like some advice about how
easily the spindle, which sticks up out of the valve, *should* turn.
We've read elsewhere that it might turn with just "finger pressure",
however, without a torque wrench and some idea of what Newtons are
required, we don't know how much force is normal so don't know if the
valve may be stiff. This, no doubt is why one usually calls in the
professionals I guess!

Advice gratefully received.

There are several checks you can do to determine the state of the valve.
[You may have done some of this already]. Select CH (only) at the programmer
and turn the room stat turned up to max. If the valve doesn't open with the
actuator attached, remove the actuator from the valve and check whether it
then motors to the CH position. If it does, the wet part of the valve is too
stiff for the motor to turn - and will need to be freed or replaced. If the
actuator *still* doesn't move, you've either got a duff motor or a wiring
fault.

Another thing you can do is to turn the electrics off at the FCU which feeds
the system (not the programmer) and then move the valve to the manual
position with the lever. If, when you let go of the lever, the spring return
moves the valve back to the HW position, you know that the wet part *isn't*
seized. [Incidentally, if the wet part seizes, the motor shouldn't burn
out - it's designed to run stalled, and is powered, but stationary, in the
mid and CH positions].

My guess is that you've got a failed synchron motor in the actuator. What I
would do in these circumstances is to buy a new actuator to get it all
working again *and* buy a new motor and repair the old actuator as a spare.
Provided Screwfix say that their motor fits your valve, buy that if it's
cheaper than the Honeywell-branded one - they are probably identical anyway!
--
Cheers,
Set Square
______
Please reply to newsgroup. Reply address is invalid.

It happens that Set Square formulated :
My guess is that you've got a failed synchron motor in the actuator. What I
would do in these circumstances is to buy a new actuator to get it all
working again *and* buy a new motor and repair the old actuator as a spare.
Provided Screwfix say that their motor fits your valve, buy that if it's
cheaper than the Honeywell-branded one - they are probably identical anyway!

I concur with all of that.

You should be almost able to turn the valve with finger tips, if you
have a really good strong grip. So very light pressure to turn it with
pliers/small adjustable is fine.

--

Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.org

On 23 Aug 2005 07:42:04 -0700, wrote:

I appreciate that this is a commonly discussed matter within this
newsgroup, but the specific question we want to address/resolve is not
one we can find the answer to here, so we thought we'd ask.

We have a Honeywell V4073A valve which seems to have died, so we've now
removed the powerhead, and successfully rotated the spindle on the
valve by about 10 degrees using a small adjustable wrench and minimal
force (we didn't know whether it might have seized - we do live in a
hard water area). As a consequence, we now have just HW (which is what
we want for now, we don't want the radiators on too - before removing
the powerhead, we could get HW + CH (not ideal in mid summer) by
forcing the manual lever over to manual with a large matchstick!).

Hi

AFAIK a mid position valve should natuarly return to its midposition.
From what you say yours isnt so I'd say replace the whole thing.

Many thanks to everyone.

A few questions.

The spindle can be rotated with effort, but the key question seems to
be "how much effort" is required to differentiated a "siezed" spindle
in the wet part of the valve, from a normally functioning spindle. The
last remark that it "should naturally return to its midposition" is
confusing as it isn't clear whether the refferent here is to the
spindle or the powerhead when on top of the spindle. At present we have
the spindle exposed but rotated so we get just HW, and we have the
powerhead on the floor.

What we need to confirm is whether the powerhead, detached from the
spindle and valve, should show any life when the thermostat is turned
up and CH selected at the programmer. What we may not have picked up on
is the importance of testing the transition from no power at all to
power on again (which means isolating the powerhead and programmer from
the rest of the mains by switching off those fuses?).

Sorry to be vague here, but as things are, we still can't tell whether
the primary fault might be with a semi-siezed spindle, or a faulty
powerhead/motor. We naturally want to avoid having to replace the whole
valve as this means getting someone in to drain the system as well as
replacing the part.

Thanks again.

In an earlier contribution to this discussion,
ocidental wrote:

Hi

AFAIK a mid position valve should natuarly return to its midposition.
From what you say yours isnt so I'd say replace the whole thing.

Please don't post confusing rubbish like this when you clearly don't know
what your talking about!

A mid-position valve is so called because it has a mid position where both
CH and HW circuits are fed at the same time - rather than being a simple
diverter valve which gives *either* HW *or* CH but *never* both at the same
time.

With all power removed, the spring return on a mid-position valve will
return it to the HW position. It requires *power* to move to - or remain
at - the mid position.
--
Cheers,
Set Square
______
Please reply to newsgroup. Reply address is invalid.

In an earlier contribution to this discussion,
wrote:

Many thanks to everyone.

A few questions.

The spindle can be rotated with effort, but the key question seems to
be "how much effort" is required to differentiated a "siezed" spindle
in the wet part of the valve, from a normally functioning spindle. The
last remark that it "should naturally return to its midposition" is
confusing as it isn't clear whether the refferent here is to the
spindle or the powerhead when on top of the spindle. At present we
have the spindle exposed but rotated so we get just HW, and we have
the powerhead on the floor.

What we need to confirm is whether the powerhead, detached from the
spindle and valve, should show any life when the thermostat is turned
up and CH selected at the programmer. What we may not have picked up
on is the importance of testing the transition from no power at all to
power on again (which means isolating the powerhead and programmer
from the rest of the mains by switching off those fuses?).

Sorry to be vague here, but as things are, we still can't tell whether
the primary fault might be with a semi-siezed spindle, or a faulty
powerhead/motor. We naturally want to avoid having to replace the
whole valve as this means getting someone in to drain the system as
well as replacing the part.

Thanks again.

Ignore the post suggesting that the valve should automatically return to the
mid position. That's rubbish, as explained in another of my posts.

You should have an FCU (Fused Connection Unit/Isolator Switch/Call it what
you will) which enables you to remove *all* power from the heating system.
Switch it OFF. [If you can't find it, switch *everything* off at the meter].

AIUI, you currently have the wet part of the valve in the HW position. When
unpowered, the actuator should be in the *same* position. i.e. if you sit
the actuator on top of the valve, the D-shaped slot should line up with the
spindle without having to rotate anything.

Does it? If it does, take the actuator off and operate its lever. Looking at
the underside, you should see the D-shaped slot move round to the mid
position. Does it?

When you let go of the lever, the slot should move back to the HW position.
Does it?

Now bolt the actuator onto the valve and again operate the lever to move the
valve to the mid position. Then let go of the lever. The spring return
should move the valve back to the HW postion. Does it? [If it *does* - the
valve is OK and *not* seized].

Assuming you've answered Yes to everything so far, remove the actuator
again, turn the power back on, and select CH with the room stat turned up.
Watch the underside of the actuator to see whether anything moves. If it
*doesn't*, you've got a duff motor - or a wiring fault.
--
Cheers,
Set Square
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Please reply to newsgroup. Reply address is invalid.

In message , ocidental
writes
On 23 Aug 2005 07:42:04 -0700, wrote:

I appreciate that this is a commonly discussed matter within this
newsgroup, but the specific question we want to address/resolve is not
one we can find the answer to here, so we thought we'd ask.

We have a Honeywell V4073A valve which seems to have died, so we've now
removed the powerhead, and successfully rotated the spindle on the
valve by about 10 degrees using a small adjustable wrench and minimal
force (we didn't know whether it might have seized - we do live in a
hard water area). As a consequence, we now have just HW (which is what
we want for now, we don't want the radiators on too - before removing
the powerhead, we could get HW + CH (not ideal in mid summer) by
forcing the manual lever over to manual with a large matchstick!).

Hi

AFAIK a mid position valve should natuarly return to its midposition.

No it shouldn't

If it's spring return, it will return to it's rest position (as in the
Honeywell 4073)

The other type will remain in whichever position it was last energised
to

From what you say yours isnt so I'd say replace the whole thing.

--
geoff

In message .com,
writes
Many thanks to everyone.

A few questions.

The spindle can be rotated with effort, but the key question seems to
be "how much effort" is required to differentiated a "siezed" spindle
in the wet part of the valve, from a normally functioning spindle.

With no water flowing, "with ease"

basically, it's a brass shaft in a brass sleeve with rubber "O" rings
top and bottom. The only resistance should be that of the water

The
last remark that it "should naturally return to its midposition" is
confusing

Ignore it - it's wrong

as it isn't clear whether the refferent here is to the
spindle or the powerhead

It can only refer to the head, the paddle just goes where it's driven to

when on top of the spindle. At present we have
the spindle exposed but rotated so we get just HW, and we have the
powerhead on the floor.

What we need to confirm is whether the powerhead, detached from the
spindle and valve, should show any life when the thermostat is turned
up and CH selected at the programmer. What we may not have picked up on
is the importance of testing the transition from no power at all to
power on again (which means isolating the powerhead and programmer from
the rest of the mains by switching off those fuses?).

The power head should go where the system tells it to,

The Actual valve (wet bit) is totally "dumb"


Sorry to be vague here, but as things are, we still can't tell whether
the primary fault might be with a semi-siezed spindle, or a faulty
powerhead/motor. We naturally want to avoid having to replace the whole
valve as this means getting someone in to drain the system as well as
replacing the part.

Thanks again.


--
geoff

On Wed, 24 Aug 2005 11:28:23 +0100, "Set Square"
wrote:

In an earlier contribution to this discussion,
ocidental wrote:

Hi

AFAIK a mid position valve should natuarly return to its midposition.
From what you say yours isnt so I'd say replace the whole thing.

Please don't post confusing rubbish like this when you clearly don't know
what your talking about!

fcuk off!

A mid-position valve is so called because it has a mid position where both
CH and HW circuits are fed at the same time - rather than being a simple
diverter valve which gives *either* HW *or* CH but *never* both at the same
time.


Yea I know *I've* got one.

With all power removed, the spring return on a mid-position valve will
return it to the HW position. It requires *power* to move to - or remain
at - the mid position.
your FoS

On 24 Aug 2005 02:01:44 -0700, wrote:

Many thanks to everyone.

A few questions.

The spindle can be rotated with effort, but the key question seems to
be "how much effort" is required to differentiated a "siezed" spindle
in the wet part of the valve, from a normally functioning spindle. The
last remark that it "should naturally return to its midposition" is
confusing as it isn't clear whether the refferent here is to the
spindle or the powerhead when on top of the spindle. At present we have
the spindle exposed but rotated so we get just HW, and we have the
powerhead on the floor.

What we need to confirm is whether the powerhead, detached from the
spindle and valve, should show any life when the thermostat is turned
up and CH selected at the programmer. What we may not have picked up on
is the importance of testing the transition from no power at all to
power on again (which means isolating the powerhead and programmer from
the rest of the mains by switching off those fuses?).

Sorry to be vague here, but as things are, we still can't tell whether
the primary fault might be with a semi-siezed spindle, or a faulty
powerhead/motor. We naturally want to avoid having to replace the whole
valve as this means getting someone in to drain the system as well as
replacing the part.

Thanks again.


When I had trouble with my Honywell 3 port valve I like you had the
spindle exposed but with CH selected, but I had to have a mole wrench
holding the spindle which together with a piece of wood wedged against
the wall to forced it to stay in the CH position. If I wanted hot
water I'd remove the wedged wood and it would without any actuator or
any help from me, go into the midposition and I'd get some hot water
from the cylinder because the path of least resistance is via the
cylinder.

Your valve seems stickier than mine so in my opinion it would be more
reliable if it was changed.

In an earlier contribution to this discussion,
ocidental wrote:


When I had trouble with my Honywell 3 port valve I like you had the
spindle exposed but with CH selected, but I had to have a mole wrench
holding the spindle which together with a piece of wood wedged against
the wall to forced it to stay in the CH position. If I wanted hot
water I'd remove the wedged wood and it would without any actuator or
any help from me, go into the midposition and I'd get some hot water
from the cylinder because the path of least resistance is via the
cylinder.

Your valve seems stickier than mine so in my opinion it would be more
reliable if it was changed.

The actuator has a relatively small motor, but operates the valve through a
*massive* gear reduction - and is thus able to produce quite a lot of torque
at the spindle. The acid test is whether the spring return can move the
valve back to the HW position with all power removed. If it can, the motor -
provided it isn't duff - will have no difficulty in rotating the spindle to
the mid or CH positions.

[If in your other post you were trying to say that *your* valve gravitates
to the mid position due to water flow on the paddle with the actuator
*removed* you should have made that clear. That is quite different from
moving to its "home" (HW) position with the actuator attached. Your valve
sounds unusually floppy. Mine is quite a lot stiffer than that, but still
works perfectly happily.]
--
Cheers,
Set Square
______
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In message , ocidental
writes
On Wed, 24 Aug 2005 11:28:23 +0100, "Set Square"
wrote:

In an earlier contribution to this discussion,
ocidental wrote:

Hi

AFAIK a mid position valve should natuarly return to its midposition.
From what you say yours isnt so I'd say replace the whole thing.

Please don't post confusing rubbish like this when you clearly don't know
what your talking about!

fcuk off!

But what you said was totally wrong

Like he said, if you don't know what you're talking about, don't say it

maybe you should apologise

--
geoff

On Thu, 25 Aug 2005 20:46:06 GMT, raden wrote:


But what you said was totally wrong

No it was nt, know it all, read my other post I was speaking from
experience.

Like he said, if you don't know what you're talking about, don't say it


see above!

maybe you should apologise

maybe you should ...

Actualy I regret the out of place language against a venerable poster
and as you see I can resist that urge, but I stick with my opinion the
OP should change the valve. This is the time of year they stick after
the first time its been over to the CH side for 3 months or so.

On Thu, 25 Aug 2005 10:19:10 +0100, "Set Square"
wrote:


The actuator has a relatively small motor, but operates the valve through a
*massive* gear reduction - and is thus able to produce quite a lot of torque
at the spindle. The acid test is whether the spring return can move the
valve back to the HW position with all power removed. If it can, the motor -
provided it isn't duff - will have no difficulty in rotating the spindle to
the mid or CH positions.

[If in your other post you were trying to say that *your* valve gravitates
to the mid position due to water flow on the paddle with the actuator
*removed* you should have made that clear. That is quite different from
moving to its "home" (HW) position with the actuator attached. Your valve
sounds unusually floppy. Mine is quite a lot stiffer than that, but still
works perfectly happily.]

Ahh you have one too!

SS sorry about the tone of *that* reply.

cheers
Old Floppy Paddle.

In an earlier contribution to this discussion,
ocidental wrote:


SS sorry about the tone of *that* reply.

cheers
Old Floppy Paddle.

Accepted.
--
Cheers,
Set Square
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