Comment on Repair or not, electrical heater switching circuit
litchralee@sh.itjust.works 3 days agoI see. Given those constraints then, I don’t see any option besides a new heater. Ideally, the new heater would be built with less circuitry, so there would be fewer things to break.
Looking at the Adax Clea product description, it seems overly complicated for a radiator, IMO. I’m not sure I’d want triac switching for something like a heating appliance. Resistive heating doesn’t strictly require silicon switches, when a relay should work. But I suspect an equally-svelt radiator that’s also simple may be hard to find
BigDanishGuy@sh.itjust.works 1 day ago
A relay would do the job, but they also wear out faster and the sound is noticeable.
While writing that, I found myself thinking about how significant the life span difference is. So I did some back-of-the-envelope calculations.
The defective heater had been installed for roughly 2100 days. Sometime during April we shut the heaters off, and they’re not powered up again until October, so let’s call it 50% of the year. The schedule for the heaters is usually two power on cycles daily. Again let’s call it 50% of the time. The house is pretty OK insulated, but let’s say that the heating element is powering up 4 times each hour. In reality it’s probably closer to 25-30% and twice an hour, so I’ll use that as the lower bounds for this calculation.
1050 days is 25200 hours, meaning that the heaters will have done between 12k and 50k power cycles in the almost 6 years of operation. I’ve seen relays weld shut before 10k, but MTBF for suitably rated relays on RS starts at 50k power cycles.
So maybe a relay could actually do the job. But then there’d still be the issue of the noise, which, while negligible, could still be annoying for some, especially in a bedroom.