[b]Aristo DIA boiler, Hot water fluctuating. Heating is ok.[

[brianmath]

Aristo DIA boiler, Hot water fluctuating. Heating is ok.

Had most parts replaced.
new secondary exchanger, both sensors, pump, diaphragm, diverter valve. Also had a power flush which produced hardly anything.
Next is the main exchanger.

Hot water runs hot then cold, hot then cold. Can`t get enough for a bath.

Also is there anyway i can tell the age of my Aristo DIA boiler, eg from a serial number etc.

So far British Gas have done all this under there home care cover but i`m losing all confidence in them. Now into the sixth week.

Any info on this would be appreciated.
Brian M

 

[meldrew's_mate]

Can you see the flame?
If so get someone else to run the bath, does it start large, then reduce, then go off, before relighting, etc.?
Does it burn with a large flame continuously?

I'm not familiar with the Aristo(n?), but if it has demand lights do they go on and off in sequence with the water temperature?

How much did BG charge for the power flush (around here they don't include it on the service contract)? If they did that properly the main heat exchanger will be clear, assuming it isn't partially blocked with plumbers' mate or ptfe tape!

 

[gasgeezer]

could be sticking gas gov. on the meter had this many times spec, if gov. a dunkin.

 

[brianmath]

Yes you can see the flame, appears to constant to me. Have noticed though as i starts to heat up the boiler makes a strange noise, hard to describe - almost a hissing noise as it`s boiling. Appears to be coming from the top end of the boiler. May be it is the main exchanger. Then cuts the flame before going through the cycle again.
Also noticed i get the same noise a hissing noise as it`s boiling if the heating is cranked up when that kicks in, seems ok if heating at its lowest & kicks in.
Temperature stays to about 40 - 60 degrees, never higher ever if fully turned up.
By the way British Gas charged £440 for what i consider to have been a total waste of time.

Bri
++++++++++++++++++++++++++

Boiler doesn`t have any lights as you asked.
Boiler is Ariston DIA 24.

Thanks for the tip on a sticking gas gov.
Got British Gas coming again on Monday with a new main exchanger, will mention this to them as i think they are scratching there heads with this one.

Any more suggestions appreciated.
Bri

 

[gasgeezer]

sounds like a blockage not circulating properly had one and changed dhw haet/ exch this cured it but you have prob on heating as well with parts you have changed and syst flush would point to main heat exch/ or filters possibly sluggish pump or air in syst. is aav open

 

[brianmath]

Don`t understand is aav open.
Also what do you mean by filters.
Can you explain.

I`m getting familiar with the boiler & it`s workings, but i`m just an end user.

Cheers again
+++++++++++++++++++++++

By the way it`s a new pump.
The air in system you mentio, would that not have been cleared when they done the power flush.
I assume they have to drain & refill system (i wasn`t there when they did this)

 

[ChrisR]

SOlution here seems absolutely clear to me, no question at all. Therefore I have to assume I don't understand the problem!

None of the treatment so far would have cleaned the domestic hot water heat exchanger (heats tap water from boiler water). This ought to be done when a powerflush is done but I haven't heard of it being done so far. Any BG bods comment?

is this a dia24mffice? Loads of similar Ari's.
GC 4711604?

If so it has a can type secondary heat exchnager (grey cylindrical thing). Toss up whether its easier to clean by removing or doing in situ. I prefer to remove but it can be time consuming. New ones don't cost the earth.

 

[brianmath]

It`s just had a secondary exchanger, as i stated in my 1st message above.
(small grey cylinder thing at the bottom)
++++++++++++++++++++++++++++
Yes, the boiler in question is an Ariston DIA 24 MFFICE.

_____________________________________
moderator

please note 10a & 5 which are here

 

[ChrisR]

as i stated

I thought I was senile but matron wasn't here to ask.

SOme of the aristons get blockages in the vital waterways around the secondary heat exchanger. There aren't many, take the pipes out and check. Often where a temperature sensor screws in.[/quote]

 

[Agile]

Its all right! Chris has just come back from darkest Africa and he has not been the same since!

He even passed a curry meal out. The only time he has ever done that before is when his primary heat exchanger blew up on the way!

Tony

 

[brianmath]

I`ll mention all this to the engineer today.
Would this blockage not have cleared with power flush i had done on Friday.
Anyway, thanks for all your advice. I`ll let you know if the new main exchanger works today & i`ll probably be back for more advice.

Cheers again

 

[brianmath]

Just had the call i`ve been waiting to hear.

Main exchanger replaced & all problems solved.

Many thanks for all those who offered advice on this.
Bri