For UK listees As far as the UK is concerned, under the insurance cover most of us operate there is nothing to prevent one operating a stainless steel boiler; it's just that club boiler inspectors are not permitted to test them under our test code. So if you wish to operate a stainless steel boiler you will have to get it tested commercially. Harry Wade summed it up succinctly; > The bigger issue is stress corrosion cracking. The initial and > continued measures necessary to make a welded SS boiler predictably safe in > the long term is well beyond the amatuer. The average club boiler just does not have the facilities to test the boiler or the knowledge to make a valid decision about its forward life. -- Regards Mike Leahy South Ockendon, UK MODEL ENGINEERING DISCUSSION LIST. To UNSUBSCRIBE from this list, send a blank email to, modeleng-request@xxxxxxxxxxxxx with the word "unsubscribe" in the subject line.