maple1
Minister of Fire
My power failure boiler protection consists of an 1000W pure sine inverter with built in charger/transfer switch and a group 27 marine battery. It provides seamless transfer from line power to battery power in the event of power failure and back when line power comes up again and then will automatically recharge the battery. More than enough capacity to run the boiler and circulator for a burn cycle or two. Yes not a solution for a several day power outage but great for boiler protection for the power failure that happens during a burn cycle. It is the blue box mounted on the wall to the right of the boiler. Inverter/transfer switch/charger combo at zoro.com - less than $300, battery ~$100
The other boiler protection concern would be the failure of the circulator itself during a burn - my solution is to use the European solution that we seldom use in the US, the boiler overheat connections provided in nearly all European manufactured boilers. That plumbed through a Watts STS20 thermostatic valve and connected to domestic cold water will run cold water through a loop internal to the boiler for protection during an over heat situation. (note I don't have it installed yet in this pic). IMO (Assuming domestic cold water is available) this is much simpler and compact than running a bunch of tube and fin above the boiler somewhere to provide a gravity overheat loop and not to mention powering a Normally open valve all the time to keep the valve closed in normal operation. I found the Watts STS20 valve for ~80 shipped from an ebay seller in Germany, they are available for a bit more from US suppliers. The rest is just cold water piping and a drain to out the back of my boiler building.
Different solution that works for me - I didn't want a bunch of tube and fin blocking the view of the TV
View attachment 256912
Yes I thought I had myself covered with the UPS, and it has done its job lots of times the past few years. But this is the first time I couldn't get it to switch on when I needed it. It seems to need hooked to power to switch. If it is plugged into power & switched on, then the power goes out, it is all hunky dorey. But if it is not switched on, and the power goes out, then you try to switch it on - well, yesterday it wouldn't. Not sure yet what I will do when the batteries in it need replacing, that cost will be pretty large. (It's an APC SmartUPS 2200va - oldie but goodie).
I also have those Euro hookups on my boiler, but never hooked them up. I would need to find a drain to run to, and in an outage my water pump would be dead also. So didn't bother. Different solutions fit different situations. And the more you can install/set up, the better in this case - this is the one aspect that redundancy should be standard.