Ravenheat, heating comes on when only tap water required

[LondonLandlord]

Hi all. Please can you help.
I have a Ravenheat combi boiler, about 7 or 8 yrs old.
It works fine but when the heating is off (in the summer) and a hot water tap is turned on, BOTH the water AND the heating come ON.

Hot water comes out fine in the taps but also the radiators start getting hot. And YES, the switch is on Water Only, not heating. I double checked that many many times.

A plumber came out and claims it is the divertor valve and will cost £140 part plus $120 labour!!
I found the part on Ebay for £45.
But do I really need it?
Is there something else that could be the problem?

Please help as I only have a day or two to make a decision.
Massive big up Thank You to you all who reply. Seriously, dont what I would do without all your help.

 

[ljrgas]

are you paying the engineer in pounds or dollars?
my opinion is 120 reasonable.

But do I really need it? well yes you do if you want the boiler to function correctly.

depending on the model it could be the divertor or a diapham.

probs better off replacing ravenscrap rather then fixing the thing

 

[Agile]

Whilst yuo can buy used, dodgey, stolen diverters from ebay for delivery 3-6 days later an engineer has to pay the proper price to get them over the counter the same day.

Its also a knuckle scraping job to change too!

With the last one that I did I had to take a jammed part home to get it apart in a vice with heat applied.

Tony

 

[Agile]

Whilst you can buy used, dodgey, stolen diverters from ebay for delivery 3-6 days later an engineer has to pay the proper price to get them over the counter the same day.

Its also a knuckle scraping job to change too!

With the last one that I did I had to take a jammed part home to get it apart in a vice with heat applied.

Tony