Baxi 105,hot water problem

[Groovejet]

Has anyone come accross a baxi 105 only knocking out average temp water, until cold tap turned on, then get plenty hot water
The thing is it didnt happen b4, so it cant be a problem with high pressure on the cold main
Any help please

 

[Agile]

You have limited flow into the property.

Turning on cold tap is reducing the DHW flow rate.

You can get the same effect by turning the hot flow back down a little!

Simple!

 

[Groovejet]

Pooohhh!

 

[Boilerman2]

Come on OP you clearly state that when you turn on the cold tap, the hot tap increases and gives you "plenty hot water" Quote

This is the same as turning the hot tap down the flow rate through the boiler will drop if a cold tap is turned on.

I suspect your problem is simply low incoming water temp combined with c**p in the plate heat exch.
now cut your attitude and go away!!