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46 minutes ago, Home Farm said:

Can’t I just replace the motor?


You can but they take some work 

 

Isolate the power and clip the connections off for the motor - they have no polarity. 
 

Take the 2/3 screws out holding the motor to the body and withdraw it - the cam should stay in place but watch the return spring doesn’t come loose. 
 

Put the new motor in, screws into place and then use the manual lever to move it forward and let it return back under the spring. 
 

Connecting the wires either uses the crimps provided or a standard barrel crimp depending on the supplier. 

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2 minutes ago, Home Farm said:

Sorry for all the questions, but is the head visible here?

04900F3F-F859-4B2A-866B-CC33B7E68060.jpeg


All the bit inside the steel box is the head. The motor is part of it, as is the microswitch etc 

 

The brass bit that it is mounted on is the valve. 

 

 

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4 minutes ago, PeterW said:


You can but they take some work 

 

Isolate the power and clip the connections off for the motor - they have no polarity. 
 

Take the 2/3 screws out holding the motor to the body and withdraw it - the cam should stay in place but watch the return spring doesn’t come loose. 
 

Put the new motor in, screws into place and then use the manual lever to move it forward and let it return back under the spring. 
 

Connecting the wires either uses the crimps provided or a standard barrel crimp depending on the supplier. 


How would you grade this in terms of difficulty? I’ve never done this kind of thing before. 
 

The instructions are above are to replace the motor, correct?

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11 minutes ago, Home Farm said:


Thanks Peter. Handy skills are improving every day :) 

 

what is the head, and why would that be sufficient to address this issue I’m now facing? 

By "Head" he just means the whole actuation caboodle, the "head" could be unbolted and chucked and a new one bolted on.

 

These things are very simple; it is to all intents and purposes an electrically operated valve, a motor/servo turns, moves some bits via a pinion gear and rack usually or just two gears. Often the issue is plastic gear teeth actually, the pinion is usually metal (often brass) but the others are plastic and they wear or a tooth breaks off and the thing cannot work on the motor anymore - chances are the motor is actually OK, it could certainly have failed but more likely an actuation issue from the drive gears.

 

Do you know this valve is getting the "signal" i.e. a supply to actuate it? If so I would suggest you just change it out on this occasion and next time you will have more to knowledge to play with. If it was me I would take it apart and cut new gears in brass!

 

 

Edited by Carrerahill
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Just now, Ed Davies said:

 

…including the steel box.


so this is the head? I know it says motor, but it’s tiny and when I looked at it the shop through the bubble wrap it looked like the head.

951A3F85-DD2B-413C-B7D7-BC5026469AD3.jpeg

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Before I comment the actuator lights on the manifold and all thermostats are calling for heat, but no hot water is getting through in auto. 
 

when I open it (manual) hot water gets through as the pipe heats up instantly. 
 

I assume this is all pointing to a head replacement. This is another steep learning curve for me.

 

thanks to everyone for your patience.

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6 minutes ago, Home Farm said:


so this is the head? I know it says motor, but it’s tiny and when I looked at it the shop through the bubble wrap it looked like the head.

951A3F85-DD2B-413C-B7D7-BC5026469AD3.jpeg

According to the part no. on the side and a quick Google search it appears to be just the motor with an integral gearbox:

 

https://www.screwfix.com/p/drayton-synchronous-motor/28670?tc=ET5&ds_kid=92700020956158103&ds_rl=1241687&ds_rl=1245250&ds_rl=1249404&ds_rl=1249799&ds_rl=1245250&ds_rl=1249481&gclid=CjwKCAiAyeTxBRBvEiwAuM8dnb3pVx19nwtu5X8NA6JZ5eL4liyTvPdCK_LVKYXDA2ldTHlkdaMLIxoCQQoQAvD_BwE&gclsrc=aw.ds

 

Note the brass pinion gear as mentioned above.

 

I would pull the motor off, then have someone call for/cancel the call for heat (wait a bit between as it is not always instant) and see if the motor spins - just leave it hanging safely and watch it. 

 

Then look into the hole where the pinion gear goes and see if you can see mashed teeth - if mashed teeth this motor will not help.

 

 

 

 

Edited by Carrerahill
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4 minutes ago, Home Farm said:

When I open it (manual) hot water gets through as the pipe heats up instantly. 
 

I assume this is all pointing to a head replacement. This is another steep learning curve for me.

Yes - it is quite a common fault in these systems. My in-laws had these replaced about every 2.5 years until British Gas finally replaced the cheap part that they fitted on the first fault call out with a Honeywell and it has been fine ever since - the engineer told my father in law that the one he fitted was all metal gears and would not fail for a long time. 

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23 minutes ago, Carrerahill said:

would pull the motor off, then have someone call for/cancel the call for heat (wait a bit between as it is not always instant) and see if the motor spins - just leave it hanging safely and watch it.


Is the motor visible in the pic I attached previously?

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1 minute ago, Home Farm said:


Is the motor visible in the pic I attached previously?

Yes the silver round thing, also look at my link to Screwfix which shows what it looks like in isolation. Look like it will be 2 or 3 small screws that hold it on and 2 wires which you can just leave alone.

 

 

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3 minutes ago, Home Farm said:

Sorry guys. I’m so incredibly confused. Is the motor inside the head? These parts are all looking the same to me. 
 

Can I use the Drayton inside my existing chassis?

On the back of your motor, it says Synchronous Motor - Original - 230V etc... then there is a code, what is the code, I can't quite make it out. However, looking at your motor, and the box you posted a photo of and the cross reference of the part No. I did, I think yes from what I can see.

 

You could always take your motor to the parts store and ask to compare the new one out the box.

 

Look at my link and your motor, they certainly look very similar to me... they all tend to use the same motors and parts as few people actually make them, Drayton & Honeywell etc.

 

However, if in doubt run the part no. physically engraved in the back of your motor through Google and check. What make of valve do you have? 

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13 minutes ago, Carrerahill said:

Go make a cup of tea/coffee and view this.

 

When he says "top piece" that is what has been called a "Head" above.

 

 Terrific video. I’m empowered!

 

what this has prompted me to test, before I change the motor is whether the motor is getting instruction from the Heatmiser wiring box. If it is, the motor us dead.

 

if it’s not getting that instruction, then we have a different issue. 
 

is my reasoning correct?

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On 01/02/2020 at 07:22, Nickfromwales said:

Basically what we need to know is, if, when the heating is turned on / off, does the brown wire get energised / de-energised ? If it does then the controls that are giving the signal are fine and the motorised head is duff. 


I’m ready to do this... I’m armed with my new multimeter but unsure where to attach the probes to conduct this test. Also, on the multimeter, do I set it to V 200 or 600?
 

today is a crazy learning day.

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On 01/02/2020 at 09:09, ProDave said:

I asked earlier if you have a multimeter?  If you do, follow the cable coming out of the valve head it will go to a junction box or a wiring centre.  Measure with the multimeter set to ac volts between the brown and the blue core.  If there is no voltage, it is a control fault.  If there is 240V there and the valve is not opening then the motor has gone and you need to replace the valve head.


similar question to what I’ve Nick, I guess.

 

Do I set the multimeter to 200 or 600. Which probe do I attach to which cable? Black is COM and red is max 600V.

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40 minutes ago, Home Farm said:

The code is VAL222MV 

 

If I take this motor off, do I gave to disable my central heating?

No - it isn't working anyway. Just ensure electrical connections are made safe (terminal block or a tape even for a temp fix).

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Just now, Home Farm said:


similar question to what I’ve Nick, I guess.

 

Do I set the multimeter to 200 or 600. Which probe do I attach to which cable? Black is COM and red is max 600V.

600 as 200 is peak 200 so will read a null reading, yes black to COM and red to the max 600V (there may be another terminal which will be for non-fused current measurement up to about 10A).

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That is what I thought. Thanks for the confirmation.

 

Just need to know which terminal goes on which cable... or won’t it make a difference as it’ll just switch between positive and negative readings?

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