OK, got you.
So when I get the third party engineer out, do I also ask him to remove this valve and install the electric conventional controls for the boiler and hot water?
Relay Problem
- Thread starter Holly64
- Start date
OK, got you.
So when I get the third party engineer out, do I also ask him to remove this valve and install the electric conventional controls for the boiler and hot water?
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That is definitely NOT a relay, it is a 3-port valve - forget the word 'relay' your boiler guy didn't know what he was talking about.
The 3-port comprises two main components, the actual water valve and the head or proper name the electrical motorised actuator. On the side of the actuator is a lever (not a switch) moving that will manually open the valve and should cause the boiler to fire up and heat the radiators. Moving that, may even free it up to work normally if it was simply stuck.
The actuator is supposed to turn the valve, to the correct position to supply either HW, or CH, or maybe even both at the same time.
Roughly how it works is - Your HW thermostat or CH thermostats click on with a demand for heat, those signals then go to the actuator, the actuator then turns the pump and boiler on once it has moved the water valve to the correct position.
No, you already have perfectly 'conventional controls'.
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You could spend a lot of money upgrading to much more up market controls, but if what you have suits your needs their is no need.
Your guy seemed to not have much of a clue at all about heating systems, he was probably just a trained monkey to do one job - that of servicing a boiler and issuing a bit of paper. He was not an heating engineer. You are wasting money paying the company a regular (monthly?) fee, thinking what ever goes wrong with your heating, they will fix. In fact they will only fix your boiler and often if they cannot be bothered, they will say it is obsolete, parts no longer available and try to sell you a new system.
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Tell him to bring a "Synchron" motor.
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The motorised valve has V3 micro switches inside it that can stick causing the fault you have, some times as a temporary fix if you latch the bleeding leaver over the heating will work again, however when summer arrives you will find the radiators get warm when the DHW is heated, so only a temp fix.
With the two port valve it acts as a relay, but with the three port valve it is more complex than that, this is how it is wired inside the valve
but the valve has been a standard unit in central heating for many years very common in the 70's, the advantage was the boiler could cool by heating the DHW even when there was no power to the boiler, today boilers have a cool down period built in, but years ago they just switched off, and this valve as default is DHW so it lets the boiler cool as water can still get through the pump when it is stopped.
Today we tend to use two port valves and by-pass valves, which we call S Plan but with the old boiler the Y Plan you have was very popular.
The guy who came to repair the system it seems was not a heating and ventilating engineer, anyone trained to over level 3, i.e. an engineer would have known that was a motorised valve, not a relay, I will admit as an electrical engineer the first time I came across the Y Plan I found it hard, as those resistors and diode inside the unit gave me reading I had not expected. But it was not really my job, although it was a micro switch failed, normally either the motor or whole valve is changed, depends if you can get the motor head on it's own.
But do try latching the bleed lever, that did work with daughters system.
Oh I see that is what the video shows, with S plan it will not cause boiler to run, but with your Y plan it does, or at least it did with daughters, but when summer comes, each time DHW runs it gets the radiators slightly warm, so only a temp fix.
With the two port valve it acts as a relay, but with the three port valve it is more complex than that, this is how it is wired inside the valve
Today we tend to use two port valves and by-pass valves, which we call S Plan but with the old boiler the Y Plan you have was very popular.
The guy who came to repair the system it seems was not a heating and ventilating engineer, anyone trained to over level 3, i.e. an engineer would have known that was a motorised valve, not a relay, I will admit as an electrical engineer the first time I came across the Y Plan I found it hard, as those resistors and diode inside the unit gave me reading I had not expected. But it was not really my job, although it was a micro switch failed, normally either the motor or whole valve is changed, depends if you can get the motor head on it's own.
But do try latching the bleed lever, that did work with daughters system.
Oh I see that is what the video shows, with S plan it will not cause boiler to run, but with your Y plan it does, or at least it did with daughters, but when summer comes, each time DHW runs it gets the radiators slightly warm, so only a temp fix.
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The lever is not meant to activate the switches. It is to manually open valve when filling the system.
99% of failures on these are due to motor failure !!
https://www.google.co.uk/aclk?sa=l&...iikpDC_azuAhVPfMAKHe4YBxkQ9aACegQIBxBU&adurl=
99% of failures on these are due to motor failure !!
https://www.google.co.uk/aclk?sa=l&...iikpDC_azuAhVPfMAKHe4YBxkQ9aACegQIBxBU&adurl=
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I have only ever had one motor fail, but numerous jammed actuators and failed microswitches.
We have yet to even confirm the problem is the 3-port which has failured.
OK. So my central heating system is supposed to cover the actual pipework as well as the boiler. I am being told a 'Relay Switch is not covered' but it is not a relay switch. It is a 3 way port valve. So, if a 3 way port valve is covered, they should send out a different engineer to fix it?
Did I just get that right?
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Does your cover include control gear,or ,Specifically Exclude them ?
Must admit I was bamboozled the first time I had to fix my own heating system, there is nothing conventional about how those 3-port actuators function. They are a rather clever design, to make them cheap, simple to make, simple to install, but not much to them once you study the diagram and fix a few.
Eric - I very much doubt the OP will be able to fix their own problem, so its pointless explaining how they work and how they can be repaired. It even looks tricky getting the head off the valve, the way it is orientated. The best we can hope for is to get her some temporary heating working, until an engineer can be found to fix it.
Holly - Turn both the room and the hot water cylinder thermostats to maximum and try moving that lever on the 3-port. Then let us know the result, if the boiler fires and you get some heating. You will have to control it manually, turning the whole heating system on and off via the switch, but at least you will have heating and in the meantime can get a proper engineer out, telling him you have an issue with the 3-port actuator.
If they cover the whole heating system, not just the boiler alone, YES they have let you down. Tell them to send a proper heating engineer to fix your heating system and you could maybe add that you suspect a problem with the 3-port valve.
When you ring them, ask for a supervisor.
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As the boiler and pump are obviously working when the valve is closed (De energised h/w position). It is my experience over a long working career that 99% of the time it will be a failed motor. Stalling them in the mid position for long periods even when in off periods cannot help.
I used to buy 10 per month when I had a Housing Association maintenance contract.
Well they are stalled by putting them on a DC supply (diode) and via a dropper resister, so maybe not all that drastic. Which component fails first, is maybe down to the make and model of actuator.
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