Glow worm hx24 f22 after draining down

[Gasguru]

So it's a Flexicom HX24 then...
Run the boiler and look in the manual and pull up D40 & D41 diagnostic codes...that will give you the temperatures for the flow and return pipes.
If these temperatures are too wide (and/or probably too narrow) within a set time versus the burner output it will throw an F22.
Are you sure the pump is operating, the system isn't air locked somewhere etc.

The fact that the wiring is a bodge and the pump overrun has also been bodged (probably in order to avoid a new cable run back to the boiler) may be indicative of a poor system layout pipewise.

 

[sotal]

So it's a Flexicom HX24 then...
Run the boiler and look in the manual and pull up D40 & D41 diagnostic codes...that will give you the temperatures for the flow and return pipes.
If these temperatures are too wide (and/or probably too narrow) within a set time versus the burner output it will throw an F22.
Are you sure the pump is operating, the system isn't air locked somewhere etc.

The fact that the wiring is a bodge and the pump overrun has also been bodged (probably in order to avoid a new cable run back to the boiler) may be indicative of a poor system layout pipewise.

If I'm honest, I don't think the pipe layout is the best ever, I'm looking into running a cable from the airing cupboard to the boiler whilst the floor is up. Would a length of 2.5T&E be sufficient. There must be a cable already to follow as it initiates the boiler.

Then when the electrician comes I could get him to swap it over so it is powered correctly.

The pump is definitely operating well. I don't think there is an airlock now and water is flowing through the boiler. The pressure from the drain off on the return pipe a few inches above the boiler send greater than that of the flow pipe above the boiler.

From me logically thinking it through (which isn't the best given my limited knowledge of heating systems) I still think that when I drain down it must pull sludge down from the header tank in the loft. If that is now partially blocking the f&e pipe would that not reduce the pressure and throw the f22 code?

 

[Gasguru]

2.5T&E has no place in a boiler...flexible 0.75mm multicore should be used.
You'd normally have 4 core & earth from the boiler to the wiring centre where the pump etc are located.
Why would you not bale out and clean the header cistern before draining down....not doing so is the fastest way to wreck the boiler/pump etc.
See what the temperatures are....

 

[sotal]

2.5T&E has no place in a boiler...flexible 0.75mm multicore should be used.
You'd normally have 4 core & earth from the boiler to the wiring centre where the pump etc are located.
Why would you not bale out and clean the header cistern before draining down....not doing so is the fastest way to wreck the boiler/pump etc.
See what the temperatures are....

Well now I know! I'll be cleaning the header tank out next time.

I think I've hopefully sorted it, it is now running. I used some thin garden wire and poked it as far down the f&e pipe as I could. The boiler has now been running for 15 minutes or so with no issues. Radiators all getting warm.

I now plan to run some system cleaner for a week then flush through and replace with inhibitor.

I'll start investigating the wiring as the electrician is coming a week on Wednesday but I need the floor down before he comes. If I can lay the majority of it then hopefully he can connect it up.

The boiler is in the utility room at the back of the house. The cylinder, wiring center, y valve, pump etc. Are all in the airing cupboard which is about 13m away. I'll see if I can work out what is there already.

I have vague memories of the new boiler being installed. The old one was ancient. It had a mechanical time clock on the wall in the garage but otherwise pretty much the same setup. The mechanical time clock had some sort of mains wires going into it. The installers put a standard blanking plate over it.

 

[Gasguru]

The older boilers only required Switched L,N&E whereas most modern boilers require Permanent L,N&E and Switched Live and Pump Live.
Sometimes, it's possible to run the cable externally along the wall...using black round trunking and circular access boxes it can look ok.
There's also a wireless option...mainslink.