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Mike the Boilerman 

Your independent Potterton 

Netaheat specialist covering Berkshire, Wiltshire & surrounding counties

For more information or to book your breakdown repair, call or text me on 

07866 766364 

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Asbestos in Netaheats: 

I get asked regularly by members of the public if Netaheats contains asbestos so there is clearly a lot of interest. The answer you will probably find disappointing and predictable. Some do, others don’t. There now, was that helpful? Thought not…

To comment meaningfully we need to find out which version of Netaheat you have. I suggest you check through the photos on my “Identify your Netaheat” page then come back here knowing your exact model.

Identifying asbestos can only be done with 100% reliability in a laboratory but to me, asbestos looks clearly recognisable compared with the later (and safe) mineral fibre seals. Asbestos seals are pale grey rather than white, and are clearly made of loose fibres prone to shedding when disturbed. Here is a series of photos of seals from various Netaheats, labelled according to what I think they are made from, in order to illustrate the subtle difference in appearance of each type of seal. I may however be wrong!

Netaheat Original:

I rarely see these but from memory I think they all have friable asbestos seals around the removable front panel of the combustion chamber, and under the flue hood. These two seals need to be disturbed to carry out normal servicing. The Mark 1 Netaheat probably has asbestos seals at the back too, between the boiler backplate and the flue tube through the wall. This is just a guess though. I’m consequently reluctant to repair a Netaheat Mk1 in case the fault lies in the combustion chamber. If anyone needs to disturb the combustion chamber or flue hood seals, its best in my opinion to spray them with water from a plant sprayer (or WD40 from a can) to thoroughly wet the fibres and reduce the risk of any fibres being released into atmosphere. Better just replace the boiler in my opinion if you have one, as few parts are available to fix a Mk1 and due to the asbestos risk. 

Netaheat MkII:

Similarly to the Mk1, I think all MkII Netaheats have asbestos seals on the flue hood and the combustion chamber front panel, so I prefer not to work on them unless the fault lies only in the controls box underneath, and the combustion chamber front panel does not need removing. If anyone here has a MkII with the more modern and safe glass fibre rope seals instead of asbestos, please get in touch and I’ll amend this page. Thanks! 

Netaheat MkIIF:

This is the tricky one. I’d say 75% of the MkIIF Netaheats I see inside have modern safe glass rope seals, and 25% have asbestos. I’ve yet to figure out if there is a way of telling externally which MkIIF have asbestos so if you have a MkIIF, the best I can say is there is a significant chance yours does.

Netaheat Electronic:

I’ve never seen asbestos in any Netaheat Electronic. I can’t say definitively but of the many hundreds (possibly thousands!) I’ve seen inside, I’ve yet to see an asbestos seal or anything at all made from asbestos. This is no guarantee there are none out there anywhere though! Potterton also sold Netaheat Electronics in the USA for example, and I’ve never seen inside one of those and USA laws relating to asbestos are probably different from ours here in the UK.

Netaheat Profile:

As above, this is an even younger model than the Electronic above and I’ve never seen an asbestos seal inside a Netaheat Profile. Nor the later but identical, re-named version the “Potterton Profile”.  

In a casual conversation I had many years ago with a chap at Potterton, he told me that use of asbestos in boiler manufacture was banned in 1984, so any boiler made by anyone after this date is guaranteed to contain no asbestos. He said Potterton reduced and then stopped using asbestos several years before 1984 so slightly older Pottertons probably still contain no asbestos, but there was no definitive cut off date earlier than 1984.

Hope all that helps….



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Details here

Asbestos seal 1 on Potterton Netaheat
Ceramic fibre seal 1 on Potterton Netaheat.
Asbestos seal 2 on Netaheat flue hood.
Ceramic fibre seal 2 on Netaheat flue hood.
Asbestos seal 3 on Netaheat flue hood.
Ceramic fibre seal 3 on Potterton Netaheat
Ceramic fibre seal 4 on Potterton Netaheat
Ceramic fibre seal 5 on Potterton Netaheat
Asbestos seal 6 on Netaheat flue hood.
Asbestos seal 4 on Netaheat flue hood.
Asbestos seal 5 on Netaheat flue hood.

Asbestos seals in this left hand column.

Ceramic fibre seals in this right hand column.

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Copyright Michael Bryant 2021

Site first published 11th November 2010

Last updated 7th June 2021

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