Zone control not working, anything I can check myself?

mrcheez

As luck would have it just as the cold arrives the zone control for my upstairs zone has gone kaput.

So far I've only observed it doesn't turn on when I activate it at the time clock, whereas it did fine a couple of days ago.

It's only 2 years old, is there any thing i can try testing myself before calling a plumber?

meercat

there should be a lever on it to open manually

Sometimes by moving this lever and letting it spring back,the valve will free up

There’s a groove to keep the lever in place should you require

mrcheez

https://www.boards.ie/discussion/comment/124048255#Comment_124048255

I'll give it a shot thanks… rather annoying as I had both zone controls replaced only 2 years ago when they died.

salmocab

just on the off chance there’s hardly a wall stat that has been turned down?

mrcheez

https://www.boards.ie/discussion/comment/124048360#Comment_124048360

nothing has been changed in the house… one day it's working, the next it's not

mrcheez

https://www.boards.ie/discussion/comment/124048255#Comment_124048255

So i got a chance to access the zone control today and pulled the lever but unfortunately hasn't helped.

On the upside the heating is on now, though I dont believe it turns off with thermostat valves now and just stays on until I unclick it.

I dont suppose a valve replacement is something straightforward like wiring up a plug? Or does it require emptying the system?

meercat

if it’s a faulty valve it should be a straight forward swap

No plumbing required

Some valve even have a push connector so no electrical work either

post a few photos of it

youtheman

Normally, all that turns on your heating is 'any one zone valves open'. So if you manually opened the valve (withe the lever) and your heating tuned on that means that you boiler is working o.k. It's a problem with the controls.

So is your zone valve opening when you try to operate it via the controller?. If not it is either a controller, a thermostat, a faulty valve or a wiring problem.

mrcheez

https://www.boards.ie/discussion/comment/124051321#Comment_124051321

The controller? You mean the time clock where I turn on the zones, or the box the two zone valves are wired into?

mrcheez

These are the 2 zone controls and "the box" on the right, I assume that's the controller?

The problem control is the left one.

Space is pretty tight so I'd probably need to buy one of these to unscrew it

https://www.amazon.ie/STANLEY-066358-Multi-Bit-Stubby-Screwdriver/dp/B003KQ5EFM/

mrcheez

so… what ye think? Easy enough to replace, or a complex job?

meercat

assuming that’s the issue it’s a straightforward replacement

5 wires like for like

2 screws to release from pipe work

only issue is tight workspace

salmocab

https://www.boards.ie/discussion/comment/124053837#Comment_124053837

I’d say assuming is the big word there. Faulty stat or loose connection could cause the issue too

mrcheez

https://www.boards.ie/discussion/comment/124053837#Comment_124053837

Just so I understand, how is it actually interfacing with the pipe? Will replacing it not risk water suddenly getting released from the pipe?

Also where do I buy these? I looked at the Danfoss website and no idea what they are called.

meercat

https://www.boards.ie/discussion/comment/124053959#Comment_124053959

https://www.heatmerchants.ie/danfoss-hpa2-2-port-valve-actuator-only-339366

unscrew 2 chrome screws to separate from pipe work

No water will be released

mrcheez

I wonder if there's any use in just taking the cap off the current one I have and doing the manual switch and see if cogs aren't moving or something like that?

Maybe the issue is with the wire box on the right side?

Perhaps I can see what's broken before deciding on next step

youtheman

Did the boiler turn on when you manually opened the valve (via the lever)?.

mrcheez

Yup...does that mean wire box OK?

youtheman

https://www.boards.ie/discussion/comment/124056360#Comment_124056360

If your boiler started when you operated the lever manually then that means your boiler is working o.k. and the limit switch in your zone valve is working o.k.

So you need to do the following:

1. for the zone in question, turn down the thermostat (you should hear it click).

2. whatever you use (i.e. controller) turn the zone on. Nothing should happen as the thermostat is turned down.

3. go to the thermostat and turn it up fully. When you hear it click your zone valve should open (you should hear the motor operating the valve), and your boiler should fire.

John.G

https://www.boards.ie/discussion/comment/124056360#Comment_124056360

The boiler should not turn on when you open the valve manually, that facility is only for refilling the system (or draining), its a safety interlock in case the system is empty when you open it.

The boiler should start if the programmed zone is timed to come on or is set to manually on or Boost on a lot of programmers plus the roostat or cylinder stat must be calling for "heat", the valve should then open fully, when it does, a set of auxiliary or end contacts in the valve actuator will/should close to fire the boiler.

mrcheez

Right, so it will involve recording a video as my zone valves are downstairs and thermostat is upstairs

Will test tomorrow cheers

mrcheez

https://www.boards.ie/discussion/comment/124057275#Comment_124057275

Not sure i follow 1st paragraph. When I turn valve on manually the pipes get hot so surely means boiler is on?

Also steam comes out of flue

John.G

When you open the valve manually, the zoned system associated with that (zone) valve should only get hot if the boiler is already running if another zone valve has been programmed open.

mrcheez

Hmm its possible the downstairs one was on alright, I'll add that to the list to check tomorrow

salmocab

https://www.boards.ie/discussion/comment/124057309#Comment_124057309

been a while since I was at one but if you turn the valve manually using the switch on the side does that not close the switching pair on the MV? Surely that would give the boiler the signal to fire?

Very open to being wrong it’s years since I was at one

John.G

https://www.boards.ie/discussion/comment/124057804#Comment_124057804

When you pull on the lever to manually open it, you actually then have to push it upwards to make it latch in, it probably opens ~ 80/90%, if you subsequently programme the valve to open, the motor will drive it the rest of the way open and the lever will "fall down" and unlatch. When programmed off, the valve will then always close fully.

youtheman

https://www.boards.ie/discussion/comment/124057275#Comment_124057275

Not correct. Normally, all that turns on your boiler is all the zone valve limit switches wired in parallel. So any zone valve open will turn on the boiler. Including moving the level manually to open a valve. Your controller sends 220 volts through a thermostat and onto the motor of the zone valve. So that is what normally opens the valve.

declan b

https://www.boards.ie/discussion/comment/124057275#Comment_124057275

IF the double pole spur switch is turned on before the time clock which it always is . It sends a permanent live to all the motorised valves [ normally to the grey wire ] . With all zones in the off position at the time clock and the motorised valve is turned to the manual position the boiler will start. ie motorised valve in the manual open position connects the permanent live grey wire to orange wire to the boiler through the microswitch in the motorised valve and the boiler starts

youtheman

https://www.boards.ie/discussion/comment/124058300#Comment_124058300

It depends on the boiler. For my gas boiler all you need is a 'volt free' or 'dry contact' to turn on the boiler. In my Firebird Oil Boiler you need a switched live to turn on the boiler. Either way, it is the zone valve limit switch (only) that gives you the signal (either volt free or switched live). So that is why, if you have problems with you boiler, you manually open any zone valve. This will help you determine if it is a boiler on controls issue. If the boiler start when you manually open any zone valve they you can determine with 100% certainty that the boiler is o.k.

John.G

I can certainly state that on my 2 port Honeywell valves that moving the lever manually to open the valve does NOT open it sufficiently to close the microswitch in the actuator, also, when de energised the valve has only to move very little to open the microswitch again, I'm also almost sure the Myson 2 port operates similarly, can't comment on any other 2 port valves.

declan b

grey wire to permanent live,orange wire to boiler/pump or visa versa. the micro switch is only a switch.