actuator issue

Conar

I used to have 3 myson zone valvesin the hot press and 2 failed.
I called out a plumber and he told me my son always fail and he had a better brand to replace them with. Anyway he had to drain the system and installed them but a couple of years later they've both failed. The house has been rented out so I have to replace them.

Went to the local plumbing supplies place and they've told me that I need to install new valves as the ones I have (peglar terrier tzv22) are no longer available.
Their website also shows them as discontinued.

I was hoping I could just replace the actuators myself as I am a little more clued in than I was originally.

Looks like I can't just put on the myson actuators as the plate is different. In the pic attached the plate on the left is for the terrier (also mounted on the right) and the middle is the myson one.

Anyone any ideas if I can get a replacement or if I'll need to drain it again and installed new valves.

Dtp79

Conar wrote: »

I used to have 3 myson zone valvesin the hot press and 2 failed.
I called out a plumber and he told me my son always fail and he had a better brand to replace them with. Anyway he had to drain the system and installed them but a couple of years later they've both failed. The house has been rented out so I have to replace them.

Went to the local plumbing supplies place and they've told me that I need to install new valves as the ones I have (peglar terrier tzv22) are no longer available.
Their website also shows them as discontinued.

I was hoping I could just replace the actuators myself as I am a little more clued in than I was originally.

Looks like I can't just put on the myson actuators as the plate is different. In the pic attached the plate on the left is for the terrier (also mounted on the right) and the middle is the myson one.

Anyone any ideas if I can get a replacement or if I'll need to drain it again and installed new valves.

I think Honeywell do a valve very similar to the terrier. Not sure if they can interchange though. But that's not the real issue here. I'd say your motorised valves are wired incorrectly and are opened by a switch or something similar. There being held open and they eventually burn out
And there's absolutely nothing wrong with myson valves if wired properly

Merch

Dtp79 wrote: »

I think Honeywell do a valve very similar to the terrier. Not sure if they can interchange though. But that's not the real issue here. I'd say your motorised valves are wired incorrectly and are opened by a switch or something similar. There being held open and they eventually burn out
And there's absolutely nothing wrong with myson valves if wired properly

Ive looked up zone valves online so I can understand how they work, to see what might best suit me as I keep hearing of burned out motors. I wante to get something that will last as long as possible withotu being replaced, like the OP.
It seems the synchronous motors operate either open or closed, one side being powered and stalled and the other side unpowered? they always seem to be powered when stalled and this seems to be the reason they burn out, eventually? from what I can gather.
Whats the expected life of zone valves?

I originally thought they would have microswitches to power off at the limits of operation, but it seems the valves only power off on one side (presumably closed).

Conar

I'll probably just have to replace the 2 with valves included.
How much should a plumber charge for this ballpark?

Dtp79

Conar wrote: »

I'll probably just have to replace the 2 with valves included.
How much should a plumber charge for this ballpark?

If you just replace them they'll burn out again in no time. Get them wired up properly. A straight changeover wouldn't be that expensive

jjf1974

Dtp79 wrote: »

If you just replace them they'll burn out again in no time. Get them wired up properly. A straight changeover wouldn't be that expensive

Why do you think they are not properly wired,every motorised valve i ever saw is simply opened by switch (thermostat,timer etc) once power is going to valve it remains open,when the power is disconnected it closes.There is usualy 4 or 5 core cable coming from the valve ,the blue and brown power the motor that opens the valve the others often grey and orange go to a switch on a circuit that closes once the valve opens.

Dtp79

jjf1974 wrote: »

Why do you think they are not properly wired,every motorised valve i ever saw is simply opened by switch (thermostat,timer etc) once power is going to valve it remains open,when the power is disconnected it closes.There is usualy 4 or 5 core cable coming from the valve ,the blue and brown power the motor that opens the valve the others often grey and orange go to a switch on a circuit that closes once the valve opens.

Because in my experience electricians just cut away the orange and grey switch wires. Then it's just open/close with a timeclock or switch. Thing is though this switch is always left turned on, forcing the motor in the valve open for way longer than it needs to be. If the OP is getting this many valves failing then this might be his problem

Condenser

Dtp79 wrote: »

Because in my experience electricians just cut away the orange and grey switch wires. Then it's just open/close with a timeclock or switch. Thing is though this switch is always left turned on, forcing the motor in the valve open for way longer than it needs to be. If the OP is getting this many valves failing then this might be his problem

Its definitely not as the orange and grey are for an auxillary switch and so have nothing to do with the proper operation of the valve.

Could there be lime in the water causing the valve to stay in the open position and therefore causing the impression that the actuator is faulty or not closing?

jjf1974

Can you check to see that there is power coming to the valves when they should be open .if you have a phasetester you should have power on the brown .If both valves failed at the same time you may have a problem with a timer or a room stat.

Dtp79

Condenser wrote: »

Its definitely not as the orange and grey are for an auxillary switch and so have nothing to do with the proper operation of the valve.

Could there be lime in the water causing the valve to stay in the open position and therefore causing the impression that the actuator is faulty or not closing?

It's unlikely that lime would affect the heating system (maybe heat exchanger). I understand what your saying about the auxiliary switch. OP, what's controlling your zones??

shane0007

Condenser wrote: »

Its definitely not as the orange and grey are for an auxillary switch and so have nothing to do with the proper operation of the valve.

Could there be lime in the water causing the valve to stay in the open position and therefore causing the impression that the actuator is faulty or not closing?

What he is saying is they are normally by electricians via a switch to the motor. This is left permanently on by the homeowner & only switched off in the summer. The aux is not wired back to the boiler so no interlock. Having the motor permanently powered has the motor permanently putting pressure on the spring to keep the valve open. They do not last as they should and are not wired as the manufacturer intended them to be.

Dtp79

shane0007 wrote: »

What he is saying is they are normally by electricians via a switch to the motor. This is left permanently on by the homeowner & only switched off in the summer. The aux is not wired back to the boiler so no interlock. Having the motor permanently powered has the motor permanently putting pressure on the spring to keep the valve open. They do not last as they should and are not wired as the manufacturer intended them to be.

You just have a better way with words Shane!

jjf1974

shane0007 wrote: »

What he is saying is they are normally by electricians via a switch to the motor. This is left permanently on by the homeowner & only switched off in the summer. The aux is not wired back to the boiler so no interlock. Having the motor permanently powered has the motor permanently putting pressure on the spring to keep the valve open. They do not last as they should and are not wired as the manufacturer intended them to be.

I understand what you and DTP are saying now. some electricians might take this shortcut allright.I suppose the best thing for the op to do is to get a good electrician to look over the whole heating circuit.

jjf1974

Dtp79 wrote: »

I think Honeywell do a valve very similar to the terrier. Not sure if they can interchange though.

The honeywell v4043H sold by www.screwfix.com looks identical to your terrier valves ,If these actuators are the same they could be easily fitted to your valves without draining the system.
They also sell drayton synchronous replacment motors which they claim fit most actuators .They are about £10.49 sterling.I wonder did anyone on here ever fit these they look like a great solution .

Conar

jjf1974 wrote: »

The honeywell v4043H sold by www.screwfix.com looks identical to your terrier valves ,If these actuators are the same they could be easily fitted to your valves without draining the system.

Thanks for all the replies guys.
I needed to get it sorted and quick so I just got a plumber in. He's here now installing them. I got myson valves installed so I can easily replace if I have issues again.

Will confirm fixed shortly hopefully.

Condenser

Dtp79 wrote: »

It's unlikely that lime would affect the heating system (maybe heat exchanger). I understand what your saying about the auxiliary switch. OP, what's controlling your zones??

Lime can cause spring return valves like myson etc to stick in the open position or not fully close. Seen it happen plenty of times.

Conar

Condenser wrote: »

Lime can cause spring return valves like myson etc to stick in the open position or not fully close. Seen it happen plenty of times.

I have a good water softener so shouldn't have been that. Also its a closed system which had been cleaned out before and soft water put in.

I got what I thought was a good price for the 2 new myson power valves and fitting so not much more than it would have cost me anyway.

Dtp79

Conar wrote: »

I have a good water softener so shouldn't have been that. Also its a closed system which had been cleaned out before and soft water put in.

I got what I thought was a good price for the 2 new myson power valves and fitting so not much more than it would have cost me anyway.

60 a piece incl vat

gdavis

there is a site that tells u which actuators are compatible with which .cant for lfe of me remember name but im sur if u google actuator compatible motorised valves or similar it will pop up,im just too lazy!

Conar

Dtp79 wrote: »

60 a piece incl vat

Including fitting and call out what would you expect so?

Dtp79

Conar wrote: »

Including fitting and call out what would you expect so?

It really depends on the hassle I get refilling the system to be honest. If its straight forward your probably looking at 180 ish for supplying and installing the 2. I'm sure others will have other prices! what kinda bill were you hit with?

Joey the lips

i have sold myson and terrier for a long time. tbh i think they both had equal problems. my attitude was the good thing about myson was there heads were interchangable.

Conar

Dtp79 wrote: »

It really depends on the hassle I get refilling the system to be honest. If its straight forward your probably looking at 180 ish for supplying and installing the 2. I'm sure others will have other prices! what kinda bill were you hit with?

225. Seemed reasonable, I'm surprised you'd have done it that much cheaper. Regardless I needed it to be done quickly so I'm happy enough with that price. Thanks for the input though guys.

Dtp79

Conar wrote: »

225. Seemed reasonable, I'm surprised you'd have done it that much cheaper. Regardless I needed it to be done quickly so I'm happy enough with that price. Thanks for the input though guys.

Well I was allowing 60 labour for an hours work at best

shane0007

Dtp79 wrote: »

Well I was allowing 60 labour for an hours work at best

A wee story with a moral:
Missus has banging pipes for years whenever heating is on. Drives her nuts. Various plumbers tried to resolve the problem over the years but never could.
She calls Paddy. Paddy comes round & says sure I can fix that no problem. She says "Oh please, Paddy, fix it, fix it, it's been driving me nuts for years". So Paddy tells her to turn on the heating, listens for moment, then takes out his lump hammer & decides on a particular pipe travelling down the wall & whacks the pipe with one destinctive blow.
Silence!
Missis is overcome with joy. She grabs Paddy with an almighty hug & screams "oh thank you, Paddy, how can I ever thank you?"
"How much do I owe you?"
Paddy a says "€100".
Missus says "What? A €100? For hitting a f***ing pipe".
Paddy says "Ah yes, Missus, but it's knowing where to hit that f***ing pipe, you are paying for my knowledge & experience!"

The moral of the storey is always value your expertise & knowledge, for if it were that easy, they wouldn't be calling you in the first instance!

Have fun!!!

Dtp79

shane0007 wrote: »

A wee story with a moral:
Missus has banging pipes for years whenever heating is on. Drives her nuts. Various plumbers tried to resolve the problem over the years but never could.
She calls Paddy. Paddy comes round & says sure I can fix that no problem. She says "Oh please, Paddy, fix it, fix it, it's been driving me nuts for years". So Paddy tells her to turn on the heating, listens for moment, then takes out his lump hammer & decides on a particular pipe travelling down the wall & whacks the pipe with one destinctive blow.
Silence!
Missis is overcome with joy. She grabs Paddy with an almighty hug & screams "oh thank you, Paddy, how can I ever thank you?"
"How much do I owe you?"
Paddy a says "€100".
Missus says "What? A €100? For hitting a f***ing pipe".
Paddy says "Ah yes, Missus, but it's knowing where to hit that f***ing pipe, you are paying for my knowledge & experience!"

The moral of the storey is always value your expertise & knowledge, for if it were that easy, they wouldn't be calling you in the first instance!

Have fun!!!

Ya reckon 60 too little?

Conar

Dtp79 wrote: »

Ya reckon 60 too little?

Could 60 really cover fuel, vat and everything else?

Dtp79

Conar wrote: »

Could 60 really cover fuel, vat and everything else?

Ah maybe I was being too nice. Obviously if anything over a few miles travel was involved I'd charge more. Luckily enough for me all my work is within a 20 mile radius

jjf1974

Had the plumber an ideas on why the actuators keep burning out?

Irish Steve

OK, let's try and put some sanity on to this thread.

The theory of MV's is that when heat is required in a circuit, which might be radiators, or hot water, the device controlling the circuit changes state, which puts power on to the actuator of the MV, so the valve opens.

All the MV's I have here are motor open, and then spring close, so the motor holds the valve open while the zone is calling for heat. When the zone requirement is satisfied, the sensor or time switch on the zone opens, the power is removed, and the spring closes the valve. This needs 2 wires. There may be 2 or 3 other wires (excluding an earth) in the MV, and these may be used to provide a switching circuit that is used to (for example) provide power to the boiler and the pump, or pumps, depending on the circuit, so that the boiler etc only operate when there is a demand for heat, regardless of the state of the boiler thermostat, which is a good energy saving issue, there's no point firing the boiler if there's nowhere for the heat to go.

MV's can fail for several reasons. They can leak, due to wear on the O rings on the stem seal, which is common, and in some cases, the O rings can be replaced without too much trouble. They can stick, in almost any position, due to scale in the body of the valve, which can cause the circuit to operate when the controlling device is not calling for heat, and the last form of failure can be that the actuator fails electrically or mechanically, either through the wiring (usually the motor) or the gears, or the return spring can break.

The actuator is designed to hold open by the motor being stalled and held against the return spring. That is normal, and not incorrect use of the motor. If it's been set up in a way that is not controlled by a thermostat or time clock, then that's a bad design, but not as such a reason for failure. I've had MV's on my system here for over 23 years, and in that time, I've replaced some heads, and some valve bodies because of failures, but given how much they do, I'm not complaining.

If they are in a difficult place to replace, and they can be, it is usually worth considering putting a gate valve or a maintenance valve either side of them so that they can be removed for maintenance or repair without draining the whole system. Not often done, because too many builders/plumbers are cheap skates when it comes to this type of thing. If you have to drain the system to repair a MV, then its probably a good investment to put appropriate maintenance valves in while the system is drained, in the same way as it's worth considering putting maintenance valves in on radiators at the same time, for the sake of a few euro per radiator, the ability to take one off the wall for decoration without having to drain the radiator is a huge advantage, and it's much easier to deal with 2 eggcups of water than to have to deal with a radiator full. Thia is not often recommended, it costs a little more initially, but in the long term, saves the home owner when decorating or maintenance is needed. It also reduces the work required to do that maintenance.

The comments above about MVs burning out because they are open for long periods made earlier are to be honest total B$, the spring return types ARE designed to be power on when open.

Honeywell & Myson are both reputable manufacturers, and some of their heads are indeed exchangeable, as are some other makes.

Hope that makes some sense, and puts some clarity on some of the confusion that was being spread earlier

Dtp79

Irish Steve wrote: »

OK, let's try and put some sanity on to this thread.

The theory of MV's is that when heat is required in a circuit, which might be radiators, or hot water, the device controlling the circuit changes state, which puts power on to the actuator of the MV, so the valve opens.

All the MV's I have here are motor open, and then spring close, so the motor holds the valve open while the zone is calling for heat. When the zone requirement is satisfied, the sensor or time switch on the zone opens, the power is removed, and the spring closes the valve. This needs 2 wires. There may be 2 or 3 other wires (excluding an earth) in the MV, and these may be used to provide a switching circuit that is used to (for example) provide power to the boiler and the pump, or pumps, depending on the circuit, so that the boiler etc only operate when there is a demand for heat, regardless of the state of the boiler thermostat, which is a good energy saving issue, there's no point firing the boiler if there's nowhere for the heat to go.

MV's can fail for several reasons. They can leak, due to wear on the O rings on the stem seal, which is common, and in some cases, the O rings can be replaced without too much trouble. They can stick, in almost any position, due to scale in the body of the valve, which can cause the circuit to operate when the controlling device is not calling for heat, and the last form of failure can be that the actuator fails electrically or mechanically, either through the wiring (usually the motor) or the gears, or the return spring can break.

The actuator is designed to hold open by the motor being stalled and held against the return spring. That is normal, and not incorrect use of the motor. If it's been set up in a way that is not controlled by a thermostat or time clock, then that's a bad design, but not as such a reason for failure. I've had MV's on my system here for over 23 years, and in that time, I've replaced some heads, and some valve bodies because of failures, but given how much they do, I'm not complaining.

If they are in a difficult place to replace, and they can be, it is usually worth considering putting a gate valve or a maintenance valve either side of them so that they can be removed for maintenance or repair without draining the whole system. Not often done, because too many builders/plumbers are cheap skates when it comes to this type of thing. If you have to drain the system to repair a MV, then its probably a good investment to put appropriate maintenance valves in while the system is drained, in the same way as it's worth considering putting maintenance valves in on radiators at the same time, for the sake of a few euro per radiator, the ability to take one off the wall for decoration without having to drain the radiator is a huge advantage, and it's much easier to deal with 2 eggcups of water than to have to deal with a radiator full. Thia is not often recommended, it costs a little more initially, but in the long term, saves the home owner when decorating or maintenance is needed. It also reduces the work required to do that maintenance.

The comments above about MVs burning out because they are open for long periods made earlier are to be honest total B$, the spring return types ARE designed to be power on when open.

Honeywell & Myson are both reputable manufacturers, and some of their heads are indeed exchangeable, as are some other makes.

Hope that makes some sense, and puts some clarity on some of the confusion that was being spread earlier

Are you a plumber?
The guys posting here are, and their reasons for the above posts come from experience in changing MV's, burnt out due to incorrect use and being left on permenantly by the homeowner. It's not a coincidence that these valves are the ones that nearly always fail is it??