Thanks for all the comments, views and discussion about heaters. Having been a washing machine repair guy here in the UK I can say that heaters were/are extremely reliable things, I can’t actually remember replacing one to be honest. I have seen quite a few melted pumps and blackend control boards though. I only know of EBAC that makes a hot and cold fill machine now, but it still has a heater in the plastic tub. My mum’s first Automatic was a MK72 Servis and that was back in the mid 70s, it was hot and cold fill, but on most programmes took both when filling for the wash water and then used the heater to raise the temperature. The low water level (even black then) meant that what hot water went in was largely cold due to the long pipework from the hot tank. We’ve been used to heaters in washing machines for so long now (even my Mum’s Hoover twin tub had a heater in the 60s), so I guess we’re just not in the same mind set that you have in the USA from your days when you had your big agitator top loaders (which by the way I longed for as a child!).
Anyway, back to the point that we feel extremely lucky this didn’t cause a substantial fire, indeed two house down was gutted by a fire last year with a charging scooter, but that’s off topic!
When you have good paying tenants we didn’t want to mess around with this machine so it was taken away and a new one fitted within four days. I think 15 years service isn't too bad.
Thanks again for looking, lesson again is don’t leave anything going when you’re not there.
Stay safe
Alan