CH fine but no HW?

[puddleduck]

Hello

We have a Vaillant TurboMax VUW 242/1 E (or 282/1 E, I can't tell which), inherited from the previous house owners, so not sure when it was fitted etc.

About 10 days ago, the hot water stopped working. If we turn the CH on, we can get HW but otherwise the water stays cold. I thought there was a problem a few weeks ago in that it seemed to be taking much longer for the water to heat up than normal, but DH convinced me it was my imagination

The mains supply pipes have been being replaced near where we live for a few months now, and the water pressure seems a little lower than it was before, but I'm not sure if this is relevant.

We had someone out today to look at the boiler, and having taken the valves out for cleaning they said they think it *might* be the heat exchanger. I'm a bit confused by this, as how would the CH work if the heat exchanger had died?

I'm also a bit confused that the guy who turned up and claimed to be Mr Bloggs was totally different from the guy who we thought was Mr Bloggs who serviced our boiler last year - I took the phone number off last year's receipt. Is there any way I can go about finding out who the real Mr Bloggs is?! (name changed for obvious reasons, but you get the idea ).

Any explanations, thoughts, ideas or answers would be most welcome!

Thank you!

puddleduck

 

[ollski]

Would probably be looking at the diverter valve inlet filter first and also change the diaphragm while I had it in bits.....which lights come on when you try hot water?

 

[eireplumber]

if there is one thing i recall about valliant in a specific model which i cant recall the flow sensor kept sticking the fact that it was in rented accadation did help as it would be idle for periods of time. but the fact that there has been mains repair work near by would sound alarm bells ring if any dirt in the line found its way into the boiler that would cause that problem.
as to the fact that your getting hot water after or during C/H that because as the DHW pass's through the heat exchanger is being heated by the latent heat from the CH
but the flow sensor for dhw isnt isnt sensing the flow of water when you open a tap so it doesnt fire the boiler

just a thought

 

[puddleduck]

Would probably be looking at the diverter valve inlet filter first and also change the diaphragm while I had it in bits.....which lights come on when you try hot water?

None of them

When the CH is on they are all on apart from the tap one, even if hot water is coming out of the tap.

Thanks for replying!

puddleduck

 

[ollski]

if there is one thing i recall about valliant in a specific model which i cant recall the flow sensor kept sticking

Probably the aqua sensor on the turbomax with the green dials...these are great tap the numbers into the display and they tell you the fault, usually the aps, sometimes the aqua sensor.

 

[kevplumb]

Probably the aqua sensor on the turbomax with the green dials.

it aint got one (unless you count the diaphram in the diverter)

 

[meldrew's_mate]

Is there any way I can go about finding out who the real Mr Bloggs is?

Always check the CORGI I.D. card, it has a picture, registration no., and the phone no. to check with CORGI. A genuine registered installer will not mind being checked-up on (though everyone gets grumpy sometimes )

 

[ollski]

Probably the aqua sensor on the turbomax with the green dials.

it aint got one (unless you count the diaphram in the diverter)

I know Kev I was replying to Eireplumber about the model he was thinking of (turbomax plus I guess), hence the quote above it, the original problem I put my tuppenceworth in earlier....come on Kev, try harder