Boiler not suitable for the property? General advice please.

[CBW]

They said I have to keep the heating on for it to work, does that sound right?

No, it’s utter nonsense

It's currently 16.7 degrees and it won't start up at all

It’s a Vaillant, what happens if you press the 2 i buttons?

 

[cat1]

Thank you for all the help. Heating is controlled by Hive on the phone, it switches off via timer ( schedule) (not switching mains off) can't find any i buttons.

 

[MNW67]

Thank you for all the help. Heating is controlled by Hive on the phone, it switches off via timer ( schedule) (not switching mains off) can't find any i buttons.

Maybe try these buttons:

 

[CBW]

can't find any i buttons.

They’re usually on the boiler display/panel. As per @MNW67 has pointed out

 

[Madrab]

You should have the manual there, time to dig through that, that and the boiler functions should have been discussed and explained to you as part of the hand over.

 

[MNW67]

Thank you for all the help. Heating is controlled by Hive on the phone, it switches off via timer ( schedule) (not switching mains off) can't find any i buttons.

Can you post a photo of what the display is showing when the boiler isn't working?

 

[DP]

You should have the manual there, time to dig through that, that and the boiler functions should have been discussed and explained to you as part of the hand over.

Wonder if this is a contractor job.
Regardless, not fit for the purpose.
Vaillant series 4 ( heat only) of days gone by suffered from this issue which sometimes* needed a low loss header so boiler had good circulation through the relatively short loop.

Footnote*
Fitted 428 many years ago to a heating plus cylinder system. Did not use LLH, system still operating as expected.
A system boiler (series 6) I visited many years ago suffered from same issue which I could not resolve due to setup and plumbing of the system

 

[MNW67]

it's a Valiant Eco Fit Pure OV boiler

Do you also know either the exact version or the power output? The boiler comes in a range of outputs from the 412 version (12kW) to the 435 version (35KW)

Have had 2 call outs to look at system and engineers both said the boiler is too sensitive for my old house

I would think it is unlikely that the age of your house, by itself, would affect the boiler's operation. It may be that the layout of the central heating is an old design. Could you say how big the house is, how many radiators and roughly how old they are. You must have a central heating pump somewhere. Can you see what setting it is on?