V3+ not calling for heat

Laticsforlife

Bit of background - bought a Hive but realised it was not WiFi, so bought this instead.

So the boiler (Morco GB24) has a simple timer switch (heating only being controlled). Fitting the Hive meant using grey wire 4 to the NO side of the timer switch and linking Common and Live on the Hive side leaving the switch in the always on position. It worked fine.

So I used the app guide and fitted grey wire 4 to the same NO at the boiler, and to the left side of the receiver in the heating side.

It all connected to the WiFi etc, and when I increase the heat, the relay clicks and the white light comes on, but no call for heat.

I did configure it to yellow for combi boilers.

Can't quite work it where I've gone wrong, power at both ends but no heat.

Any thoughts?

NB the professional installation shows 2 slightly different wiring if it's 'potentially free' or 'switched live'. One has a link wire, but the app didn't suggest a link.

policywonk

This link contains the installation guide to your boiler.

GB24 & GB30 Series II User & Installation Instructions.pdf (morcoproducts.co.uk)

Look at Page 11 and more carefully page 16. A few things can be observed.

1. This is switched using mains power, that is Switched Live.
2. The timer has no role in controlling hot water.
3. There is a possibility of an original manual timer being installed. Does one presume right that it has not been installed?
4. The chocolate strip connector has a grey wire and red wire, on the left of the incoming power to the boiler., These two control the decision to call for heat.

Suggestions, to help you through the logic.

1. Turn off the power to the boiler. Remove the wires that screw into the points where the Room stat should fit (label them as you remove them), and fit a bridging wire between the two screw points. Turn on the boiler. Does the central heating fire up? Assuming it does, go back and undo this step.
2. Now check the wires going to wherever you've fitted that Tado wired stat.
   1. Does whatever wire connected to the Red Wire on the chocolate strip, lead to LIVE at the Stat? If not, fix the route.
   2. Does whatever connected to the Grey Wire on the chocolate strip, lead to the NO point on the Stat? If not, fix the route.
   3. Dont worry, there's nothing apart from terminals in that backplate. If you had the wiring wrong you probably didnt break anything.
   4. When (a) and (b) are correct, turn off the power again, and fit a bridging wire between the LIVE and NO terminals at the Stat. Turn it all again. Does the boiler experience a call for heat?
   5. If (a), (b) needed a wiring change fix it, then turn it off, remove the bridge and turn it all on again, refit the Wired Stat and it should work.
   6. If there isn't a wiring change needed, then your only problem is the Wired Stat.
      1. So, turn it all off.
      2. Undo that bridge in (d).
      3. Turn it on.
3. Undo the flap where the batteries are placed, and make sure that they are oriented correctly and making good contact. If you have a multimeter double check. Now grab a cuppa and stare at it, asking what you've done wrong with the configuration on the App, or come back here.

Laticsforlife

Many thanks for this, I'll work through this step by step and report back.

policywonk

Presumed it was only one wired Tado stat you fitted with an Internet bridge to replace the Hive.

Laticsforlife

Yes just one fitted .