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Discuss Honeywell 3 port diverter snag? in the Plumbing Jobs | The Job-board area at PlumbersForums.net

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G'Day fellers. Appreciate your help please:

When my boiler fires up it heats the water and radiators regardless of what is selected. I'm guessing that this means the valve is not moving from the de-energised position?

Its a Honeywell V4073A. The manual/auto lever moves freely both ways and will not latch in the man position. A test I found which involves turning the heating (only) on, holding the lever on manual then turning water on to check the valve motors across, did nothing.

A quick look under the cover shows the springs are OK and no sign of burning. The system was drained and refilled 6 years ago.

Over to you!
 
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G'Day fellers. Appreciate your help please:

When my boiler fires up it heats the water and radiators regardless of what is selected. I'm guessing that this means the valve is not moving from the de-energised position?

Its a Honeywell V4073A. The manual/auto lever moves freely both ways and will not latch in the man position. A test I found which involves turning the heating (only) on, holding the lever on manual then turning water on to check the valve motors did nothing.

A quick look under the cover shows the springs are OK and no sign of burning. The system was drained and refilled 6 years ago.

Over to you!

When you turn the power off at the Heating isolation, does it close?

How competent at Electrical work are you?
Do you have a multimeter and know how to use it?
 
No it doesn't.
Basic but safe. I'd be happy to replace a powerhead or a synchronous motor
No I don’t.....

Here’s something that may be relevant:
All the pipes are now cool but the unit itself is still quite hot!
 
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I would wait until the cold weather has really gone ...then have a play , sounds like a new head. Rob Foster aka centralheatking
 
Associated system drain? Are you asking if you can get away with just changing the head?? I would do the lot.
 
I would power off, test that it's off (pull a fuse and use a voltage tester). Remove the motor and check it over. They are normally fairly stiff to turn the cog beneath but will move. if it's jammed, replace it. They can be bought from DIY stores and are fairly cheap.
It could well be the head or valve but it is worth checking the condition of the motor first.
 
Remove the motor and check it over. They are normally fairly stiff to turn the cog beneath but will move. if it's jammed, replace it.

Ok, so remove the motor and see if the spindle can rotate:

If it doesnt, buy a new one. If it does, assume a problem with the electrical supply?

Anyone worried by the housing being hot when the pipes are cold? Would this indicate a motor trying and failing to move the valve? Wouldnt this just burn out the motor?
 
Ok, so remove the motor and see if the spindle can rotate:

If it doesnt, buy a new one. If it does, assume a problem with the electrical supply?

Anyone worried by the housing being hot when the pipes are cold? Would this indicate a motor trying and failing to move the valve? Wouldnt this just burn out the motor?
It will do that if the motor is stuck. Eventually it would burn out.
 
Wouldnt this just burn out the motor?
I don't think so. The earlier either/or valve (W-plan) definitely wouldn't, the motor stalled in the CH position, and it could stay that way all day. It dissipates about 5 watt in that condition.
I'm not 100% about the mid-position valve, but I think it probably does the same when CH only is calling. Wiring diagrams for both attached, if you want to try to work it out.
 

Attachments

  • W and Y plan wiring.pdf
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That is the plan IF the valve is faulty.
Thats why I’m trying to diagnose first.
As mentioned, if its just the motor or powerhead, i could do it myself.
If you are getting a pro in. There is no need to diagnose. He will do his own fault finding even if you tell him it is the valve.
 
It might be best to get someone to look at it. A competent Heating Engineer will be able to diagnose the fault in a short time. It may be a wiring issue.
 
It might be best to get someone to look at it. A competent Heating Engineer will be able to diagnose the fault in a short time. It may be a wiring issue.
Let’s hope note. As we all know that we love sorting out other people’s wiring.:p:p:p:p
 
Nothing worse is there.
I always completely disconnect everything from every Heating component and wiring box and start again. It's easier and quicker than trying to trace someone else's mess. Plus, once it's done I know its right.
The first time I had a wiring fault I spent 3 hours trying to trace it and got nowhere. Then decided to pull it all out and rewire. Complete and working in 30 minutes. :rolleyes::rolleyes:
 
When my boiler fires up it heats the water and radiators regardless of what is selected. I'm guessing that this means the valve is not moving from the de-energised position?

Its a Honeywell V4073A. The manual/auto lever moves freely both ways and will not latch in the man position.
1. If the rads an HW are being heated the valve has moved to mid-position. The de-energised position is HW only.
2. If the lever moves freely, the valve is stuck open. There should be resistance when the lever is move from Auto to Man, and return to Auto when released.

Try this:

Turn the power off at the main switch. (Setting HW and CH to Off at the programmer is not enough)
Check if the lever is stiff or loose.
If loose the valve is stuck open; if stiff, the valve has returned to rest position.
If there is a small bump on the top of the valve, you can remove the actuator (control box). Remove the metal cover then undo two screws (one each side) and remove motor etc. This will expose the valve spindle.
The spindle should be easy to turn by hand - but only about 20 degrees. If it's hard to turn you could try applying some silicon lubricant where the shaft goes though the base plate. (WD40 is not recommended as it can rot the seal.)

If this doesn't work, you will have to replace the whole valve.
 
No it doesn't.
Basic but safe. I'd be happy to replace a powerhead or a synchronous motor
No I don’t...

Here’s something that may be relevant:
All the pipes are now cool but the unit itself is still quite hot!
on a 3 port mid position valve if the last demand was heating the motor stays powered up until a call for hot water only pulls it back to its rest position so the valve will stay hot with pipes around it staying cold
 
Oh I love a “ max” quote when you have never seen the job lol
had a job years ago where cust said heating coming on when only hot water selected. turn up ask cust where is the airing cupboard need to check 3 port valve. no sight of valve in airing cupboard so looked elsewhere couldnt find it anywhere. eventually out of desperation looked behind the cylinder and found it had been installed first and then cylinder fitted in front of it. full drain down of system and removal of cylinder to change valve. did change pipework so it wasnt behind cylinder but cost a few quid
 
had a job years ago where cust said heating coming on when only hot water selected. turn up ask cust where is the airing cupboard need to check 3 port valve. no sight of valve in airing cupboard so looked elsewhere couldnt find it anywhere. eventually out of desperation looked behind the cylinder and found it had been installed first and then cylinder fitted in front of it. full drain down of system and removal of cylinder to change valve. did change pipework so it wasnt behind cylinder but cost a few quid

My point exactly lol
 
had a job years ago where cust said heating coming on when only hot water selected. turn up ask cust where is the airing cupboard need to check 3 port valve. no sight of valve in airing cupboard so looked elsewhere couldnt find it anywhere. eventually out of desperation looked behind the cylinder and found it had been installed first and then cylinder fitted in front of it. full drain down of system and removal of cylinder to change valve. did change pipework so it wasnt behind cylinder but cost a few quid
2 hours max:p:p
 
Try this:

Turn the power off at the main switch. (Setting HW and CH to Off at the programmer is not enough)
Check if the lever is stiff or loose.
If loose the valve is stuck open; if stiff, the valve has returned to rest position.
If there is a small bump on the top of the valve, you can remove the actuator (control box). Remove the metal cover then undo two screws (one each side) and remove motor etc. This will expose the valve spindle.
The spindle should be easy to turn by hand - but only about 20 degrees. If it's hard to turn you could try applying some silicon lubricant where the shaft goes though the base plate. (WD40 is not recommended as it can rot the seal.)

If this doesn't work, you will have to replace the whole valve.

OK Finally got everyone out of the house!

Powerhead off.
Valve tricky to turn by hand, silicon applied. Turns easily with pliers, about 20 degrees total movement.

For info: motor was still hot and auto/man lever seems to work as advertised now its off.

Back together again now. Just running the sytem to see if anything has changed.o_O
 
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The spindle should turn easily using the fingers.

If it sticks again you can get a replacement ball valve and O-ring. It's part no "272752A/U CARD". Some draining down may be required, but it saves having to remove the valve body.
 

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