Worcester 28Si ii No Central Heating - Hot water fine

[Casey744]

Hi,

We moved into a house in July and due to having to do work on it, yesterday was the first time the boiler has been turned on.

I removed the wired thermostat. The way it was wired was using a 3 core and earth wire with the neutral going to N, Live going to L, a link wire between L and LS, a link wire between N and Ns and the third wire going to Lr.

I wanted to install the regular digital programmer for the boiler so I removed the 3 core and links and put a regular cable in wiring the Live to L, neutral to N and adding the link back between Ls and Lr as stated in the manual and plugged the digital clock into ST5 on the PCB.

The hot water fires up the boiler with no problem, but absolutely nothing happens when the CH is timed to come on. I have put a mechanical clock on too and still the same happens.

Can anyone tell me where I have gone wrong?

 

[TCCHeating]

Remove the programmer connection from the pcb. But leave the link wire between lr and ls. Switch the boiler back on. Does the boiler fire for heating now? If it does it is a programmer problem. If it doesn't then it is a boiler problem.

Have you got 230v at the ls terminal? If you haven't then it is a pcb problem. You could put a link wire between l and lr instead of ls and lr and see if that works

 

[Agile]

Did you not fire up the boiler for heating BEFORE you started touching the wiring?

Tony

 

[Casey744]

Tony - no there was no electricity in the house.

Update - I took everything out of the PCB re-connected it all and the CH now kicks in when there is a demand. However, it ignites, makes some noises for 30 secs and then gives up.

If you then turn the hot water on, the boiler bursts into life as normal. When it's turned off, if there is still demand for the CH it tries again only to give up again 30 secs later.

No hot water seems to be leaving the CH flow pipe as it stays cold. Could the issue be with the pump? Although if the hot water works fine, wouldn't that mean that the pump works?

 

[Agile]

No, as the other thread eventually says, the pump is not needed for hot water and only operates for CH.

It sounds as if your pump is not working.

Either power and not turning or no power.

Tony

 

[Agile]

Even having no power originally, I have to say that as soon as there was power then I would have tested the boiler for heating BEFORE I started making any wiring modifications!