But that situation wouldn't be any different to the OP's current position – no paperwork would have been created, so the new owner would need to have it certified if they wanted to steam it in public.

Rob

What is its volume and working pressure?

regards Martin

Edited By Buffer on 21/03/2023 09:49:34

To my mind the whole boiler problem is one of risk management. When a boiler is operated in public, the risk is that the operator will be held responsible for any and all damage resulting from and accident. As the cost of an accident can be off-the-scale expensive, it pays to insure against it. Necessary because the cost of life changing injuries to a child can easily run into millions and if it's your fault they will come after your house and assets.

Running in private is a game changer to my mind. Excluding others is a good way of avoiding the risk of heavy damages after an accident. If the worst happens the only person with a claim against the operator is the operator. If he ends up maiming himself, that's his problem (mostly). A whole bunch of legal and financial liabilities disappear when the operator and victim are the same person.

The risk of personal injury in home workshops is widely accepted by Model Engineers. The risk is moderate – people occasionally end up in hospital – but our workshop accidents are extremely unlikely to affect innocent passers-by. UK government accept the risks of DIY, which is far more dangerous than Model Engineering, by not charging for NHS treatment.

So if I were Russell, operating in private, I'd take the precautions needed to ensure my personal safety and not attempt to meet the higher standards needed to run in public. Not a boiler expert, so I'd take advice but I'd:

• Assume the boiler is untrustworthy – approach pessimistically, wear safety glasses, and screen it
• Keep the working pressure low, and control it with
• A trustworthy pressure gauge and a tested safety valve (or two), ideally the 'pop' type because they dump excess pressure quickly
• Fit a trustworthy water gauge, and make sure the firebox is never allowed to run dry.
• Before firing up the first do a 2x working pressure hydraulic test. Red alert if it fails for any reason, ask for advice.
• Inspect carefully before and after each run.
• Don't mess with experimental firing methods or force the fire.
• Do regular deep maintenance (look inside) including 1.5x pressure tests. How often would depend on how often and for how long the boiler was run.
• Never assume it's safe if all goes well for years on end! Christen it 'The Widow-Maker' and don't forget it's never been properly assessed by a 'competent person'.

If it were me, I'd be a little more formal, and improve the to-do list by writing a 'Risk Assessment'. Not complicated – it's a table summarising 'What could possibly go wrong', with 'How bad is the impact it does go wrong?', 'What can sensibly be done to stop it happening?, and 'What will I need to do if it does happen?" Then ask someone else to comment! Risk Assessments are only as long and complicated as needed. A Model Boiler feels like a couple of A4 pages maximum.

For private steaming only, I wouldn't worry too much about soft-solder provided the boiler passes the hydraulic tests and I guarantee to avoid overheating by supervising the boiler at all times. Silver-solder is better because it's stronger and has a higher melting point, but many boilers were soft-soldered in the good old days without causing obvious mayhem.

Nor would I worry unduly about Buffer's next owner concern. No-one buying a second-hand boiler should ever assume it's safe without doing their own due diligence. As boilers are expensive, it's not unknown for naughty folk to forge certificates. This one, I'd put a label on it – "Warning Uncertified Pressure Vessel, Might Explode".

Dave

Not likely I’m afraid – tinman’s or plumber’s solder was recommended right up to the 1970’s in published designs and it was suggested by LBSC more than once that silver solder on threaded stays (unlike copper rivets) could crack.

I personally doubt it, but it is there in print.

Edited By Nick Clarke 3 on 21/03/2023 14:47:25