Issue with off peak boiling of water on A class boiler.

My pulsacoil A-class boiler does not appear to be heating the water overnight.

I have ensured the top tank is filled to the max water line. I have also checked the PCB and there are no error codes (all FF) and the front red light is not flashing, basically the boiler seems to be in full working order- but I'm just not getting hot water.

When I turn the on peak booster on it boils the water and we have hot water for say 24 hours but then it goes cold again.

Is there anything that I can do to either diagnose or fix the problem myself?

Hi
Have you checked the bottom heater?
And the relays too.
Mike
MGC/H2O
Norfolk

I'm not sure how I check the bottom heater or the relays?

Is it somethings that is easy to do, and would I need any equipment to do it?

Yes you do need some equipment.
Which some DIY persons would or may have.
If you need someone to attend to your unit.
On the home page is a list of advertisers, may be one in your area.
Or if not go on Google and look for one in your area.
Eg; Type in Gledhill repairs Norwich or Norfolk.
Gledhill repairer Norwich or Norfolk.
Or Pulsacoil A class in where ever.
Gledhill may cover your area, or may recommend an engineer.
Mike
MGC/H2O