Well, this week I faced this problem and diagnosed that the plate heat exchanger (PHE) had become scaled up.
This is caused by the cold water passing through the boiler, being heated, and then depositing limescale on the heat exchanger.
The best way to solve this problem is to replace the PHE, but this can be expensive.
The other option is to have the PHE flushed out.
This involves a special pump/flushing sytem and some quality descaling chemical.
This particular boiler is now running like new again, and another happy customer has been created!

Ok, so with a new month comes a brand new property maintenance project, in Bushey, Hertfordshire. Its a four bedroom detached house that is being renovated top to bottom. AMPHS's role in this property maintenance project will be to decorate throughout, bathroom design, bathroom installation, tiling and laying laminate flooring throughout the house.
I'll be posting progress and pictures as we go, and look forward to meeting the client's month-end deadline.