Should I replace 20yr old boiler with heat exchanger bunged up causing kettling

[Albertbooy]

Hi everyone


Great website and a very good reference point for the lay person and pros in some cases thanks
Need some advice please

The Kit
1. Make: Potterton Netaheat 80e about 20 years old
2. 2 Room Thermostats (Honeywell DT90E Digital) each covering half of the house (Heating in winter left on and temp set at 19.5) Boiler cycle 3 times in an hour with the Thermo setting
3. 14 rads in a bungalow
4. Grundfos pump
5. Gravity fed system


Issue: Kettling noisy boiler on firing up it sort of gurgles then when running Kettling(bubbling noise) starts and also there is whooshing noise through radiators and when the hot water cylinder is filling up a rushing whooshing noise is heard.


Remedies tried and other work done:
Power flush
Fan replaced (old one was whining),
PCB board replaced as the ignition was not firing
thermostat on boiler replaced
New Pump (old one vibrating bearings were going)

Outcome:
Power flush seemed to have made the whooshing noise much more noticeable even long after boiler has stopped. Had the engineers back and they say it must now be the Heat Exchanger that is still gunged up which the power flush couldn’t clean sufficiently so is causing the Kettling and all the whooshing noises. The Grundfos pump is set to 1 to reduce the whooshing noise through rads

Can you please in your professional opinion advise if it is:
A. worth replacing the Heat exchanger £450 plus the installation costs
B. Getting it cleaned by removing and putting it in acid(as I have read on some forums) - not sure cost and effort
C. Replacing the boiler all together which could be upwards of £2500 where a new heat exchanger is around £450 plus the installation costs.
D. Leave it and put up with the noise or is it causing damage


I would really appreciate your views and advise as I really do not want to spend another dime on a potential lame duck


Yours respectfully
Albert

 

[Leo21]

A= no

C= replace boiler, don't spend that kind of money on an old boiler.

D= yes

 

[Albertbooy]

Cheers Leo21 for the quick succinct response. I was also told many times by the 2 pervious engineers that this was one of the best boilers that you could get at the time and if you could, try to keep it going. Wool been pulled over my eyes by any chance

 

[Howsie]

Change it for something more efficient. False economy spending money on it now IMHO.

 

[diamondgas]

Advice hmmmm ... bungalow and gravity tends to say to me cylinder in loft maybe? doesn't have to be I know!

Advice would be to have it replaced with a combi minimum depends on your hot water needs and cold water supply to be honest ... ! AND how deep your pockets are

A modern condensing boiler will save you a fortune in gas I'd imagine?

 

[Leo21]

The old Netaheat was a great boiler, the noise is what it is. Just a noise. But don't spend to much money on it. At the end of the day it's an old boiler.
Your previous engineers have told you to keep it, they haven't tried to sell you a new one. So they're not trying to have you over.

 

[Albertbooy]

Thanks to all those that responded so quickly. The consensus points to me replacing the boiler. Ho hum looks like I will have to dig deep into those pockets.
thanks again chaps

 

[Chalked]

Control box worth good money second hand and as for the gas valve !!

potterton netaheat electronic gas valve type 25k49h-49 402872 907219 used | eBay

 

[Reg Man]

The old pots were great, but unfortunately are past their sell by date, which is a shame because they were so reliable and bullet proof. With energy costs today, its a no brainer to get a modern efficient boiler.

 

[Jonwells]

Replace boiler, make sure the system is cleaned properly with new boiler fitted, and fit filter, Magnacleen professional 2 is always my choice.