OK, so the room stat needs to be set a bit lower then, once you get it sorted out and working. Room stat should click off, once all CH demands have been met.
CH boiler cuts out after 4 mins. HW ok
- Thread starter aveatry
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OK, so the room stat needs to be set a bit lower then, once you get it sorted out and working. Room stat should click off, once all CH demands have been met.
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And yet again the thread is hijacked and we're going off at a tangent...
Back to the voltage measurements...
The 2 orange wires come from each zone valve microswitch.
When there is a demand from either heating or hot water 240 V comes from those zone valve orange wires and is fed via the grey wire to the boiler (probably down one of those solid 3 core and earth cables).
You need to work out when the motor is energised (as evident by the 240V across the brown and blue) there is no 240V on the orange.
The problem is either...
The motor has insufficient torque to fully open the valve and operate the microswitch...look and see but be careful as 240 V will be present under the zone valve cover.
But if the motor is fine and the switch has operated then either..
The switch is broken or 240V is not being fed to the switch...follow the zone valve grey wire back and check it has a constant 240V on it at the terminal block regardless of a heating demand.
Do not look at anything else until this is done.
Back to the voltage measurements...
The 2 orange wires come from each zone valve microswitch.
When there is a demand from either heating or hot water 240 V comes from those zone valve orange wires and is fed via the grey wire to the boiler (probably down one of those solid 3 core and earth cables).
You need to work out when the motor is energised (as evident by the 240V across the brown and blue) there is no 240V on the orange.
The problem is either...
The motor has insufficient torque to fully open the valve and operate the microswitch...look and see but be careful as 240 V will be present under the zone valve cover.
But if the motor is fine and the switch has operated then either..
The switch is broken or 240V is not being fed to the switch...follow the zone valve grey wire back and check it has a constant 240V on it at the terminal block regardless of a heating demand.
Do not look at anything else until this is done.
Thanks for your continued help
Yesterday I could not get it to come on at all but this morning it cane on by the timer but only for about 5 mins.
I have 240V at blue and brown. When heating demand is there and its not responding I am pretty sure that the motor has not moved at all as when I push the manual leaver I can feel resistance right from the Auto end. When it does move the micro switch gets hit but then the motor looses its power and drops away from the micro switch.
"follow the zone valve grey wire back and check it has a constant 240V on it at the terminal block regardless of a heating demand." Do I put both meter probes on the same grey block to do this test.
Yesterday I could not get it to come on at all but this morning it cane on by the timer but only for about 5 mins.
I have 240V at blue and brown. When heating demand is there and its not responding I am pretty sure that the motor has not moved at all as when I push the manual leaver I can feel resistance right from the Auto end. When it does move the micro switch gets hit but then the motor looses its power and drops away from the micro switch.
"follow the zone valve grey wire back and check it has a constant 240V on it at the terminal block regardless of a heating demand." Do I put both meter probes on the same grey block to do this test.
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To test the grey and the blue do I first remove the grey from the CH valve from the connector block otherwise I will also be picking up the working grey from the hot water valve. I do get 240V between the blue and the grey as measured with probe in the block.
I took the cover off the valve motor and measured 240v on the blue and brown at the motor.
Its a honeywell.
This is the label on the CH one
And this is the HW one
I took the cover off the valve motor and measured 240v on the blue and brown at the motor.
Its a honeywell.
This is the label on the CH one
And this is the HW one
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They both say Hot water only - also the label says replace with the same 4000 3916 001
Perhaps it means Hot water only and not boiling water or steem
All this time I have been testing in the blocks in the terminal box but have been getting voltages because there are 6 wires in those blocks.
I removed the case off the motor and tested there and got 0V when heating was off and 240V when the heating is on -- so looks like the motor only want to work when it likes and only for a few mins but when it does work it fully travels to trip the micro switch.
Here is where I have just tested
Now where can I get a genuine Synchron ( not synchronus) one with the blue wires that they make for honeywell
I removed the case off the motor and tested there and got 0V when heating was off and 240V when the heating is on -- so looks like the motor only want to work when it likes and only for a few mins but when it does work it fully travels to trip the micro switch.
Here is where I have just tested
Now where can I get a genuine Synchron ( not synchronus) one with the blue wires that they make for honeywell
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Thanks. Came across that one and was confused by a reviewer talking about cheap Chinese ones. I understand what he was saying now. Cheap rubbish ones are labled synchronous but the OEM ach called Synchron. There is also an issue with replacements coming with either orange or blue cable. One website I found that was very helpful on the subject were saying that Synchron made for Honeywell come with blue wires and have a higher torque. https://www.freeheatingadvice.com/a...ve_motor_fault_Testing_a_Synchron_valve_motor
I see that the motor in Toolstation has the blue wires but is £10 more than screwfix.
I hope to get one today but from my local plumbers merchant.
There should be two grey wires they are permanent lives each of the zone valves need permanent live on the grey
Yes it is a bit, I am fairly sure it is what happens when you do not wash off flux, possible plumbers maite on the threads also. I plan to give it a clean and will keep an eye on it.
An update. I have replaced the synchro motor and so far I am happy to say that it is working. Big thanks to all that helped.
Turned out that my local supplier only had "synchronus" copy motors so I carried on to Screwfix and brought the proper Synchro one there. It is packaged as Draton but the motor I think is the same. Here are some side by side pictures that may be of use to others in the future, the old one has the blue wires. Last picture is the actuator with the motor removed, I did it with the unit still in place but electric off.
Turned out that my local supplier only had "synchronus" copy motors so I carried on to Screwfix and brought the proper Synchro one there. It is packaged as Draton but the motor I think is the same. Here are some side by side pictures that may be of use to others in the future, the old one has the blue wires. Last picture is the actuator with the motor removed, I did it with the unit still in place but electric off.
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