Vokera Linea Max - Hot Water Not Very Hot

[EViS]

Looking for advice in regards to a Vokera Linea Max combi which has recently developed a fault whereby the hot water intermittently isn't always very hot. Every now and again, a bath of water or shower runs lukewarm or when turning a hot water tap on, it takes longer than usual for hot water to run.

The central heating functions fine and the pressure is at around 1.8 bar.

Any idea what could be the problem here and/or what I should try cleaning/testing/replacing first?

 

[jam1979]

its either diverter valve problem or sludged up dhw heat exchanger maybe a split in the diaphram

 

[jam1979]

try turning your incoming mains down see if this helps

 

[EViS]

Best to replace the diverter valve and clean the heat exchanger? Or replace both?

What would reducing the incoming mains flow achieve?

 

[Whn1]

It's not going to be a sludged phex if it's intermittent. You're best off getting a gsr engineer in to have a look, is it regularly serviced?

 

[EViS]

It's not going to be a sludged phex if it's intermittent. You're best off getting a gsr engineer in to have a look, is it regularly serviced?

Yup, serviced annually by a 'Vokera-only' engineer.