vaillant combi

[tsmiths]

boiler working ok except for hot water. pressure of hot water ok but its just luke warm any ideas?

 

[chrishutt]

What is hot water flow rate (litres per minute)?
What temperature is lukewarm?
What temperature is incoming cold water?
What output is boiler (24kW, 28kW)?

 

[tsmiths]

everything is still the same as it was when it was flowing hot
thought it might be something like burners need cleaning.
its a 28kw boiler and this time of year the cold water is cold no idea on flow rates
temperature gauge not registering anything. was working on saturday 18th

 

[Reg-plumb]

If you have not had anything changed recently, then it may be your diverter valve. Check the rear of the valve and see if the micro swithes are moving in for Central Heating or out for domestic hot water. if no movement, then your diaphram needs replacing in the diverter valve.

 

[scatmanjohn]

Reg-Plumb

If you have not had anything changed recently, then it may be your diverter valve. Check the rear of the valve and see if the micro swithes are moving in for Central Heating or out for domestic hot water. if no movement, then your diaphram needs replacing in the diverter valve.

WOW!!
And he hasn't yet revealed the boiler model yet , amazing

 

[gasgeezer]

depending on model it could be working on warm start only as the aqua sensor has jammed