Ariston Genus HE 24 Combi - DHW pump overrun issue

[akz786]

As above Ariston Genus HE 24 - CH works all fine.
DHW - set to 50 degrees.
Run shower at full pace - will run fine for first few mins then...
the DHW pump overrun kicks in every min or so resulting in a few seconds of a colder shower (like a constant cycle of boiler firing on and off)

Assumption is some blockage or flow restriction as its over 2 years old (warranty has run out too now)

Any help as to where the blockage may be? someone has mentioned Secondary Heater exchanger?

All help appreciated.

Thanks

Akbar

 

[Servotech]

Could be a number of things but my guess is it the plate heat exchanger.
Who fitted it? BG?

 

[akz786]

Was installed by CORGI installer from local area who is very reputable. I intend to call him back anyhow but would like to know the area at possible fault at least.

As I spoke to some other heating experts they all mentioned this secondary heater exchanger likely to be blocked, what is the function of the plate heater exchanger you mention?

Thanks

 

[ianniann]

The plate heat exchanger transfers heat from the primary heating circuit onto the flowing hot water. It consists of many narrow channels that can clog fairly easily. The hot water channels tend to clog with scale if you have hard water, while the heating circuit channels can clog with debris from radiator corrosion.

 

[akz786]

well the water is fairly hard where I live so I can expect scale build up. Is this an easy job then?

Thanks

Akbar

 

[twgas]

Could be a number of things but my guess is it the plate heat exchanger.
Who fitted it? BG?

what makes you say that.

 

[akz786]

Done some further testing last night.

So the issue is only there when I demand hot water at full speed, if I open the shower or basin tap mixer to full the flame light LED notification shows its running at full and it do this "30-40 sec cycle with pump overrun"

However if I run the shower or tap at a lower pace say half then its seems ok.

So do we think blockage in the plate heater exchanger.

BTW all my warranty etc has run out , will BG home care cover this as i think this is case for a good clean/flush and re-fill. (after reading their T&C`s its apparent this sort of issue is not covered)

 

[Agile]

Parts of Berkshire really do have hard water. I have seen some dire examples there.

It is quite possible you really do have lime scale in the plate HE. Thats particularly so if you have had a dripping hot tap !

But alternatively it might just be the usual metal oxides blocking it.

BG always avoid getting into dealing with dirt/scale/sludge work and are usually rather reluctant to even quote for it as an extra with insurance cover. I am often asked to do that for people with cover.

Tony

 

[akz786]

Thanks Tony, so do you provide services within the Berks area if so do you have contact information so I could discuss a possible quote?

Thanks

Akbar

 

[Happyplumber]

Descaleing this boiler is not difficult job,i work in berkshire and thats favourite we actually carry alot of secondry heat exchangers on the van around the area because the water is uniquely hard.

The chances are you have issues with the hot water side,rather then heating becuase of scale build up

Have look on my profile you will see a boiler i had to remove in slough because it was totally filled up with installation debris and was beyond help

 

[petit_pablo]

Who fitted it? BG?

Of all the **** we fit, thats not one of them. Why would you assume BG fitted it?

 

[nickso]

BG always avoid getting into dealing with dirt/scale/sludge work and are usually rather reluctant to even quote for it as an extra with insurance cover. I am often asked to do that for people with cover.

Tony

any BG engineer not quoting for that kind of work is a fool. at the prices BG charge their productivity goes through the roof if a quote is accepted.

 

[bobajob100]

Did you manage to cure the problem ,as I have the identical fault with my three year old Ariston Genus HE