I have a dimplex solar heating system with a water cylinder. Been fine for 5 years but in recent weeks even with hot weather I'm getting 15 seconds of hot water in the kitchen and then lukewarm water thereafter. The bathroom which is slightly further away only gets lukewarm water.
Pressure is fine. The controller wasn't touched when the issue started.
Going to cost the best part of £200 just to get it checked so any help and DIY checks you can provide would be greatly appreciated.