Honeywell 3 port valve buzzing: I know the reason and the workaround, but what if it stays buzzing when I'm away for a long time?

[alexis.chu]

Hi all. So I have this Honeywell 3 port valve that occasionnally stays buzzing when heating is off, when CH was the last call. Usually I'd either turn power off or turn HW on briefly to reset it. You know the drill, common issue on that thing.

I'm going on a long holiday this winter and I'll leave CH running in low temp mode to avoid building humidity up in the house. I'm wondering what's the worst that can happen if no one is there to reset the buzz? Can the valve overheat and fail?

Thank you

 

[HERTS P&D]

Why would you leave it and go away? Get it replaced/fixed before you leave.

Andy

 

[alexis.chu]

Why would you leave it and go away? Get it replaced/fixed before you leave.

Andy

it's been like that for the past 8 years, the buzzing hasn't gone worse + got quoted £290 (with VAT) for the job + will need a full drain + I'll sell the house in spring

 

[CountryFan]

got quoted £290 (with VAT) for the job + will need a full drain

Yikes that’s steep. Definitely a full drain down? I’m not sure I’d be leaving it. It may only need a synchron motor.

 

[alexis.chu]

Yikes that’s steep. Definitely a full drain down? I’m not sure I’d be leaving it. It may only need a synchron motor.

they quoted me for the full valve not just the motor, so I assume this'd require a full drain although I'd need to confirm with the actual technician (quote was from their office)

 

[Johntheo5]

Hi all. So I have this Honeywell 3 port valve that occasionnally stays buzzing when heating is off, when CH was the last call. Usually I'd either turn power off or turn HW on briefly to reset it. You know the drill, common issue on that thing.

I'm going on a long holiday this winter and I'll leave CH running in low temp mode to avoid building humidity up in the house. I'm wondering what's the worst that can happen if no one is there to reset the buzz? Can the valve overheat and fail?

Thank you

Assuming you are not heating the cylinder while on holidays and the cylinder stat is always calling, then you can just programme the HW to come on briefly after finishing with CH overnight?, the actuator requires a HW programmed request + the cylinder stat not satisfied plus CH programmed off to make the valve c/o to HW only?.

 

[alexis.chu]

Assuming you are not heating the cylinder while on holidays and the cylinder stat is always calling, then you can just programme the HW to come on briefly after finishing with CH overnight?, the actuator requires a HW programmed request + the cylinder stat not satisfied plus CH programmed off to make the valve c/o to HW only?.

yep that's an option

Alternatively... Correct me if I'm wrong, but if I set the switch on the valve to manual, it'll stay in CH only and presumably will never use the motor? Am I right?

 

[stem]

yep that's an option

Alternatively... Correct me if I'm wrong, but if I set the switch on the valve to manual, it'll stay in CH only and presumably will never use the motor? Am I right?

No, sadly not. The motor will still be energised by the controls.

The manual lever puts it in the mid-position [CH & HW] it's there to manually open both ports when the system is initially being filled with water to help prevent air locks being caused during the filling process.

For CH only there's no option other than the valve motor being energised so that is winds fully across and closes the HW port.

 

[alexis.chu]

I checked with my gas engineer and the £290 quote was actually for changing the motor only,not the full valve... Rip off?

 

[Mottie]

I checked with my gas engineer and the £290 quote was actually for changing the motor only,not the full valve... Rip off?

It’s only a few screws and a couple of wires. The part is less than £90. Couldn’t you do that yourself to save a few hundred quid? I’ve changed mine before now and I’m no plumber or electrician. It really was a doddle.

 

[CountryFan]

I checked with my gas engineer and the £290 quote was actually for changing the motor only,not the full valve... Rip off?

Seems like it imo, even if that's London! As above maybe change yourself?

 

[Johntheo5]

Might be safer to change the whole actuator (without valve body) instead of just the motor?

 

[Harry Bloomfield]

It’s only a few screws and a couple of wires. The part is less than £90. Couldn’t you do that yourself to save a few hundred quid? I’ve changed mine before now and I’m no plumber or electrician. It really was a doddle.

The 3-port valve heads/actuators, are such a common failure point, I always keep a spare alongside the in use actuator, ready to swap out. As above, just a couple of fixing screws, and a few coloured wires to swap over to the replacement - though some, simply plug in.

The main problem with these actuators, is that they rely on motor drive, and spring return - stalling the motor when it reaches the position, but keeping the motor powered, which is the noise you are hearing. The spring, add considerable tension on the actuator mechanism, and causes lots of rapid wear.

Better, IMHO, is the MOMO actuator, a direct electrical swap, but the valve needs to be swapped along with it. The MOMO, is more reliable in that no spring is used. The motor is only under power, when the valve position needs to be changed - as a result, the actuator runs cooler, and there is some power saving too.

 

[Deluks]

Might be safer to change the whole actuator (without valve body) instead of just the motor?

10 minute job.

To the OP, *make sure power is off before attempting this*

You can cheat by using a wago box to join new to old. You cut the old wire to the head then strip it and connect it to the wire from the new head using wagos (in a box)
Saves having to deal with a tangle of wires, fiddly little screws and the risk of getting the wires mixed up.

Before replacing the head squirt some silicone spray on the spindle and work it round and back a few times to make sure it moves freely.
Return it back to the position it was when you took the head off.

 

[alexis.chu]

Thanks all. Problem is it's been placed in such an awkward spot in my airing cupboard that I'd work almost blind.

I think I'll try my luck and keep it like this this winter, and just pre-schedule a short HW call every day when I'm away so it resets it into position.

But back to my original question: if the whole thing fails while I'm away, what's the worse that could happen?