2 port valve

[JamesBeasley]

Hello

I have searched previous posts relating to 2 port valves trying to find the solution to my problem....

My 2 port valve paddle was loose. the reason I found this out was when I switched the boiler on it would stay on full blast all the time and I tried to find the solution. I found the paddle to be loose and came to the conclusion that the valve was stuck open and gave the boiler the signal to keep going....

I have replaced the motor to my 2 port valve as the other valve seemed to be faulty. This did not cure my problem. The new valve motor's paddle is loose too. I think the reason is that the valve is stuck and the motor cannot move it. Is this right?

The reason I am on here rather than simply taking it off and trying to free it is that that valve is directly behind the cylinder and is extremely difficult to reach and remove.

If any one can help I would be extremely grateful.

James

 

[cmother1]

The way these valves work is that the motor opens them and then turns on the power to the boiler/pump by operating a microswitch. When power to the motor is cut a spring returns the valve to the closed position and cuts the power to the boiler. You can hear the motor returning under spring power if you listen carefully.
Could be that the spring has bust or come adrift or that the shaft attached to the paddle has seized (usually due to leaking and build-up of limescale).
If it's as hard to get to as you say you may have difficulty in diagnosing the problem without removing the valve. Who is it that puts things in places like this? Some pervert masquerading as a plumber...?

 

[bengasman]

Replace the whole head instead of the motor.

 

[JamesBeasley]

Thank you for your quick responses.

It is very dificult to get to the valve indeed. I'm not a big guy.... average size you could say and it took me flippin ages to do blind as i could not see it at all.

could i simply remove he head again and try turning the valve manually to free it? if i did free it would it be okay?

 

[Agile]

It just demonstrates the complete lack of common sense on the part of the installers who do that kind of installation.

I was doing a drainage job in a HA flat when the maintenance contractors came to deal with a motor valve like that!

We had a laugh about the nupty installer and then they cut a hole on the wall behind the cylinder and replaced it from the other side!

Tony

 

[JamesBeasley]

It just demonstrates the complete lack of common sense on the part of the installers who do that kind of installation.

I was doing a drainage job in a HA flat when the maintenance contractors came to deal with a motor valve like that!

We had a laugh about the nupty installer and then they cut a hole on the wall behind the cylinder and replaced it from the other side!

Tony

Won't be doing that..... Tiled wall the other side!?!?

 

[Agile]

I think it was a tiled wall on the other side but better than removing the cylinder!

Tony

 

[JamesBeasley]

I hate tiling with a passion.....

I'd rather remove the cylinder.

If I remove the motor head and the valve becomes free - would that then be free for a long time of just a matter of time before it siezed again (presuming I can free it at all?!?)

 

[cmother1]

I don't suppose you know how old the valve is, but chances are the head is held on by 2 screws. It could be very difficult getting to them.
If you remove the motor head and the shaft attached to the paddle moves freely (you may need to use pliers to turn it) then that's not the problem: it's entirely in the head.
If the shaft won't move smoothly its because the "O" rings that seal it have gone and it's scaling up. I've heard of people repairing this fault, but seeing as you need to drain down to do it, you might as well fit a new valve.
Given your aversion for tiling it looks like it's cylinder out or nothing. (Honestly, if you've got spare tiles I'd make a hole. You don't know what other problems you may create by disconnecting a sigificant amount of pipework)

 

[JamesBeasley]

I have just spent the last hour and a half remove the head that I put on yesterday and turned the shaft... with my fingers. So that is not the problem (for someone better than me to confirm please).

Could it be the programmer / controller?

Good job I got the 2 port valve for free off the mechanical guys on site eh!!

 

[cmother1]

Sounds like the sort of free gift you could live without

If you've got the bl**dy thing out test it on a bench by putting power in on the appropriate wires and seeing if the motor turns and the call wire to the boiler powers up. A test meter would help identify this. If this checks out OK the fault must be with the wiring, stat(s), or programmer

 

[JamesBeasley]

Done that.... Motor does not turn.

I doubt it's the wiring. I had the same problem before and I have just renewed the wires due to the new valve.

The thermostat on the cylinder is new (new cylinder also as old one corroded but even with the old cylinder I still had the same problem). The only thing that is part of the original system is the programmer.

What do you think?

 

[cmother1]

Sorry - I'm not quite with you here... You say the motor doesn't turn when isolated and power is put into it? Sounds like a bust motor to me....

Also by wiring I meant the whole system, not just the valve. If you're lucky you'll have a 10 terminal junction box bringing everything together and you do get things mis-wired in them. Your system should conform to some recognisable wiring scheme. Try Googling "honeywell S plan" to see the commonest set-up for a 2 zone valve system

 

[dextrous]

I may be missing the point entirely here, but isn't the paddle loose due to a programmer instructing the valve to open - it will slide freely whilst the valve has bee called to remain open.

Therefore, I'm inclined to believe that it's been wired up incorrectly more than a fault within the unit itself.