On Sun, 4 Nov 2012 06:57:27 -0800 (PST), wrote:

Motors draw many times run current during startup, and are the main
load on a modern CH system.

'tis true but they are small motors. Circulation pump 100W similar for
the pump/blower in an oil boiler. Even a little stinky 750W two stroke
generator can cope. Not even sure that the motors in circulation pumps
have a particulary large switch on surge as I think they are sychronous
(or at least brushless) rather than universal or induction.

--
Cheers
Dave.