Wiser 3 / 2-zone system – Zone 2 valve permanently open?

[Hozier]

I’ve replaced an old ESi 3-channel programmer with a Drayton Wiser Kit 3 controlling Zone 1 (downstairs), Zone 2 (upstairs) and hot water.

We moved in a year ago and had already suspected the old system wasn’t zoning correctly — some radiators seemed to come on with the wrong zone and sometimes when hot water was running.

The programmer wiring was transferred like-for-like from ESi to Wiser. At the two old wired room thermostats I bypassed the thermostat switch as instructed by Wiser, joining the live and switched-live (brown to black), as control is now via the wireless thermostats/app.

What I’ve found​

Zone 1 / Channel 1 – downstairs

• Calls for heat normally.
• Downstairs radiators get hot.
• Some upstairs radiators also heated during testing.
• Motorised valve manual lever has normal spring resistance when closed.

Zone 2 / Channel 2 – upstairs

• Calling Zone 2 produces no useful heating/boiler response.
• Upstairs does not heat normally.
• The motorised valve lever has virtually no resistance and slides freely, suggesting the valve is already open.

Hot water

• Hot-water valve appears to operate normally.
• Boiler/cylinder heating operates.
• But the upstairs radiators also become hot when HW alone is selected.

The suspect Zone 2 valve is an ESi ZV-222/W 2-port motorised valve, connected to the wiring centre by its 5-pin plug/loom.

I haven’t yet removed the actuator to check whether the brass valve spindle moves freely.

The strange part​

With the heating electrics/fuse OFF, the Zone 2 actuator lever regains normal resistance and appears to spring closed.

As soon as power is restored and the system is operated, the Zone 2 lever becomes loose/open again — including when other demands are being used.

So I’m wondering whether the actuator itself is faulty, or whether Zone 2 is receiving an unwanted/permanent live and therefore being held open whenever the system is powered. That would explain why HW circulation also passes through the upstairs radiators.

I’ve attached the original wiring-board diagram. The Zone 2 valve itself connects via the 5-pin plug and isn’t explicitly shown on the drawing.


Can anyone advise where on this wiring board I should test for the Zone 2 motor/opening supply, and what readings I should expect with Zone 2 OFF, Zone 2 ON and HW-only?

 

[CountryFan]

Do you have any electrical testing equipment?

 

[Hozier]

Just this: LAP DC Digital Multimeter 600V

 

[Hozier]

Do you have any electrical testing equipment?

Just this Just this: LAP DC Digital Multimeter 600V

 

[CountryFan]

On your motorised valve with no demands, test between the brown (Live) and earth - should be 0 volts a.c.

 

[Hozier]

On your motorised valve with no demands, test between the brown (Live) and earth - should be 0 volts a.c.

The ESi ZV-222/W actuator uses a 5-pin plug connector rather than exposed flying leads. Is there another way to test?

 

[CountryFan]

The ESi ZV-222/W actuator uses a 5-pin plug connector rather than exposed flying leads. Is there another way to test?

Probably best in the wiring center then, same wires.

 

[Hozier]

Probably best in the wiring center then, same wires.

Sorry to be dumb here - but the 5pin is also the connector circuit board. I attached picture of circuit board above but can’t figure which brown is being sent to the motorized valve

 

[BlueLoo]

The programmer wiring was transferred like-for-like from ESi to Wiser.

This is the problem.

Download all the manuals for the bits you have and draw the wiring diagram as it should be, then redo it.
I'd disconnect EVERYTHING and doing continuity tests to make sure your wires are going where they should be.

You should have a zone valve on the HW which goes to S/L on the boiler. (common with the other zone valves)
Using the boiler room stat for a wiser system is a little unusual.

You've got the right idea in drawing it out as shown, just do it for the full system.

As it stands, yours looks odd. (at least to me)

 

[CountryFan]

Sorry to be dumb here - but the 5pin is also the connector circuit board. I attached picture of circuit board above but can’t figure which brown is being sent to the motorized valve

There should be a place to test. Any photos?

 

[Hozier]

There should be a place to test. Any photos?

 

[CountryFan]

Difficult to say really, but I would say it’ll be one of those 3 as the other end/2 wires is just a switch.

 

[Exedon]

We have see those boards fail in past and rewired into a conventional wiring center.
Im fairly certain esi have discontinued that board your motorised valves are certainly discontinued.

 

[Hozier]

Thanks for all the replies so far. This is the update after continuity testing:

Update: I’ve traced the wiring further and found that the problem/upstairs stat is not actually fed from the Wiser programmer at all — and, as far as I can tell, wasn’t fed from the old ESi programmer either. Instead it has a permanent live from a separate junction behind the programmer.

The working downstairs stat is different: it is fed directly from Wiser CH1, and its switched live goes to STAT 2 (3) on the PCB.

The upstairs stat’s switched live goes to STAT 1 (3), so with the old stat bypassed its permanent live is effectively keeping that input permanently called, which would explain the upstairs valve staying open.

Even stranger, continuity testing shows the wire on Wiser CH3 — previously the old ESi CH2 heating output — actually goes to P/L (pump live/run-on) on the PCB.

So:

• why would old ESi CH2 have been connected to P/L?
• can I repurpose the existing upstairs live-feed cable so it is fed from Wiser CH3 instead, making it behave like the working downstairs zone?

 

[Exedon]

Shouldn't be any issues turning existing upstairs feed into a switched live.
What boiler do you have? having a pump overrun suggests it needs a permanent live.