smart thermostat installed. Often when I set it to be on via phone, it won’t turn on. Bad wiring or what?

[RenzoP]

When I set it to be on via phone, light A comes on (telling it to be on), but light B won’t come on, so the boiler doesn’t start. I either need to set A on and off several times via phone, or turn it off and on again via switch (C).
When I set the water to be on, it works instead, and green light B does come on.

What can it be? If the wiring had been done badly, it just wouldn’t work right? Then what it is?

- Worcester Bosh Greenstar Ri boiler
- Drayton wiser system

 

[Rodders53]

Wiser lamp (A) ON does not mean that the 'call for heat relay' is actually made (that will depend on the Room temperature measured by its wireless thermostat and the 'scheduled' temperature. + it pprobably gets more complicated if Comfort or Eco modes are enabled.

But if close to the wanted temperature the stat may not immediately call for heat - but the green light says "a heating relay is active and ready to fire up the boiler if needed".

My Wiser 3 has two heating circuits and either can make it light up.

Calling for a boost of heating should (30 min, 1hr etc.,.) sets the Room to call for +2C on the current room temperature and fires up my oil boiler - only if I OK the boost time.
on Android.

 

[RenzoP]

Thanks.. but A goes on only when I set the temperature above the current temperature (on a timer or I do it immediately. So it comes on when it’s calling for the boiler to turn on….

What can I do in these circumstances. It it just didn’t work it would have been easy to detect, I guess…

 

[MeldrewsMate]

In a typical system your Wiser output will feed to a motorised valve, 2-port or 3-port depending on the choice of the installer.
If the boiler fires up immediately the hot water is demanded then a 3-port valve is most probable, if it takes 10 seconds or so before the boiler starts to fire then a two-port valve for each of hot water (one valve) and heating (one or more valves) will be fitted.
On 3 port installations the valve may be inoperable but you will not notice this with HW only demanded, however the valve must drive open electrically to make the CH work.
Possibles are: 1. CH two-port valve failed
2. Three-port valve failed
3. Two-port (CH) or three-port valve sticking.
4. Electrical failure of output switch (usually an orange wire)
5. Something else.

You need to get someone in who can diagnose properly, or you may end up throwing parts at it until it works (the expensive way)

 

[RenzoP]

In a typical system your Wiser output will feed to a motorised valve, 2-port or 3-port depending on the choice of the installer.
If the boiler fires up immediately the hot water is demanded then a 3-port valve is most probable, if it takes 10 seconds or so before the boiler starts to fire then a two-port valve for each of hot water (one valve) and heating (one or more valves) will be fitted.
On 3 port installations the valve may be inoperable but you will not notice this with HW only demanded, however the valve must drive open electrically to make the CH work.
Possibles are: 1. CH two-port valve failed
2. Three-port valve failed
3. Two-port (CH) or three-port valve sticking.
4. Electrical failure of output switch (usually an orange wire)
5. Something else.

You need to get someone in who can diagnose properly, or you may end up throwing parts at it until it works (the expensive way)

Hi,

Thanks for your answer.
I have x2 2ports.

This is the sound the port makes when the thermostat kicks in. It sounds like it could be damaged?

 

[MeldrewsMate]

It sound like the motor is trying to drive the valve open, but no click from the end-switch could be heard.
When you turn it off does it close within about 5 seconds with a 'whizzzz' sound?
If it does then the valve will be free enough, accordingly the solution is to replace the valve head.
If it struggles to return then the valve may be semi-seized....remove the head (electrical power OFF, two screws under the steel lid), use a small spanner to exercise the valve shaft until it can be moved easily with just finger and thumb. Then re-assemble and test.