Replacement Actuator....Again!

Scorpion101

Scorpion101

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Ok so this is the third central heating actuator I've had to buy in 18 months. There's obviously something wrong with the valve.

Checking it out it looks like the valve isn't turning in the same direction as the actuator or at least the slot the valve fits into is not in the same direction. Am I going mad?

Please see the picture posted. So when I try to slot them together there is no match or at least I have to force them to match.

I'm guessing this is putting pressure on the actuator motor and causing them to fail I'm not sure how the previous occupier got on.

Am I going to have to replace the valve itself along with the actuator and if so how easy of a task is this for someone with somewhat novice skills. I've drained our system, replaced radiators, replaced actuators etc so hope that this isn't beyond me.

Thanks in advance.
 

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It's a lot easier if, as seems to be the case, you have gate valves either side.

Blup
 
The valve spindle should be able to be turned, almost with your bare fingers - if it is much tighter than that then it could be faulty. Is the actuator a spring return type? The MOMO type tend to be much more reliable.

I cannot really see how you might have installed it wrong - there are two off/ two on positions 180 deg apart, by the look of it.
 
blup said:
It's a lot easier if, as seems to be the case, you have gate valves either side.

Blup
Click to expand...

I think so there's one below and the one above is above the pump I think but has no spindle. It's just a valve which is a bit stiff. I'll add a pic. There is a spindle from the cold feed though.

Harry Bloomfield said:
The valve spindle should be able to be turned, almost with your bare fingers - if it is much tighter than that then it could be faulty. Is the actuator a spring return type? The MOMO type tend to be much more reliable.

I cannot really see how you might have installed it wrong - there are two off/ two on positions 180 deg apart, by the look of it.
Click to expand...

Yes they were spring return. I'll look at the momo type.

The spindle on the valve doesn't turn 180 degrees unfortunately. It does turn easily however It only turns at a quarter of that and it doesn't seem to match the turn of the actuator if that makes sense.
 

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Scorpion101 said:
The spindle on the valve doesn't turn 180 degrees unfortunately. It does turn easily however It only turns at a quarter of that and it doesn't seem to match the turn of the actuator if that makes sense.
Click to expand...

I would expect it to turn easily for at least a similar number of degrees that the actuator turns.

I'm no expert on valve actuators BTW, it's just that my system's most unreliable part was the 3-port spring return valve, until I swapped it for a MOMO type. No spring involved, much less stress and wear, more reliable.
 
Looks like a standard Honeywell 2 port...there's a knack in fitting the actuator to the valve body.
The spindle will only move around 20 degrees as it swings the rubber ball from port to port.
Shoe valves such as the Danfoss/Sunvic work in an entirely different manner and rotate through a full 180 degrees as the graphite shoes line up with the ports.

Set the actuator lever to manual position and set the valve spindle position accordingly.
Inside the actuator the lever plate and spindle plates don't always align due to the return spring.
When you now present the actuator to the spindle a certain wiggle is required to get the parts to fully align...once they slot into position the actuator head should be flush with the ball and lever plate.
Sometimes (I've forgotten) there's a small tit on the end of the spindle..that also needs to slot into the actuator.
Once fitted do not fully tighten the actuator retaining screws...leave them just a little loose to allow for misalignment.


https://www.fixthebog.uk/honeywell-...MIlfzy46LL7wIV2PhRCh03Wwy-EAQYBCABEgLk2_D_BwE
 
Ok. So I went and got a new actuator for the 3rd time. If this fails I will replace the valve. I've wired it up in exactly the same way as the one I've replaced. Only difference was a white wire instead of black. I have a problem. So the heating turns on fine but when the thermostat is turned down the pump stops but the valve does not close. If I remove the grey wire it will then close. Not sure what I've done wrong. I've got a pic of before. Looks exactly the same. Any ideas? Is it faulty?
 

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Post a photo of new wiring please. White wire usually associated with a 3 port valve/actuator.
 
Here's the new wiring. It's not pretty I'm affraid.
 

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So new actuator has no brown wire? What does the white wire connect to inside as per instructions? Did you purchase a Honeywell?
 
Thanks for your help. So I've removed the new one and attached the old one. Even though the mechanism doesn't work it had a handy light on it and I found that this is working correctly. So light on when thermostat triggers heat and light off when it stops. So it's definately the actuator with the problem. Whether it's faulty or I've purchased the wrong one, I'm not sure. It suggest it is a suitable replacement for Honeywell. Obviously not. I've ordered a Honeywell along with a replacement valve so I'll see how that goes. I'll try it on the existing valve first. Thanks again.
 
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