Ideal Boiler Short Cycling

[matthewjamesruddock@]

Hi,

My Ideal Logic+ 2016 24kW boiler is short cycling in 2 scenarios and I'm wondering if anyone has idea why.

On central heating, the flow temp cant be less than 77 degrees or it short cycles. In other words I can never get it into condensing mode.
I have 1x double rad 80cm long, 1x single rad 80cm long, 1x single rad 40cm long, 1x single rad 110cm long and a 120cm tall towel rail.
I think the problem may be that the boiler cant dump heat quick enough on lower temps as its oversized for the amount of rads in my 1 bed house.

However the more annoying problem is when the rads and boiler is running fine on 77 flow temp for central heating , if I use the hot water for shower or tap etc and then it goes back to central heating it will then short cycle even on the 77 degree flow temp whereas before I used the hot water it was fine.

This scenario is much more annoying as it means I cant use the hot water while the heating is on or it will cycle on and off every 2 mins, and switch off and back on wasting gas.

If anyone knows why switching to hot water from central heating and then back to central heating upsets the boiler I would love to know to prevent/fix it.

Another weird thing that might help diagnose is that the radiator flow pipe under the boiler warms up when having a shower or using the hot water which im not sure is normal or not. Its happening now in summer with the boiler on summer mode.

I have a gas engineer coming in a few weeks


Thanks

 

[CountryFan]

Flow pipe warming up is generally a sign of the diverter valve failing, which could also be why it struggles at lower heating temps, unless it is not range rated.

 

[matthewjamesruddock@]

What is range rated? I might need to ask to get that done.

 

[CountryFan]

What is range rated? I might need to ask to get that done.

It is where you can set the output of the heating, but I’ve just looked and apologies, yours doesn’t seem to support this, so might just be the diverter.