I do a lot of work with a heating contractor that has asked me to install a UPS in line with his gas boiler at his house. He wants this because during a recent power outage his generator was feeding power to the boiler burner and on more than one occasion the boiler quit and had to be reset. I don't know anything about the burner except it is fairly new and very effecient. He wants the burner to get cleaner power than his generator will deliver. I would suspect the most the burner and circulator pumps would draw would be 4-5 amps. The circp pumps are very small. I imagine I have to consider starting current on the burner motor.
I don't have any idea where to begin to buy or even size a UPS for this. The only experience I have with UPS's are the little ones that plug in for a desktop computer or commercial ones that fill a large room that I did not select. Any feedback would be appreciated.