I bought a Kipor IG1000 generator, an inverter type with an advertised "pure sine wave" output, nominally 900 W. I got it largely to run my gas central heating in the event of a power cut. I have an electronically controlled boiler with an internal fan , gas valve solenoids, and of course a pump. The mains is 230 V. The pump alone takes about 0.3 A, and when the rest is added the total is less than 0.7 A (rms).
Problem is, the boiler won't start up properly when supplied from the generator. It tries to light a few times, then gives up and switches itself off. In fact it behaves pretty well as if there is no gas supply, except that I can hear that the gas actually lights and burns for a few seconds before giving up.
The generator runs a power drill, that takes about 300 W, absolutely fine. A lamp connected when I'm trying to run the boiler doesn't flicker at all during the start-up sequence. The generator voltage and frequency measure almost exactly the same as the mains. I have no easy way to view the waveform.
I'm a bit desperate as I paid for a moderately expensive generator on the assumption that as the output was sine wave I could run pretty well anything from it within the rated VA. But I suspect that it is performing within spec so I can't reject it.
The generator manual has a large list of things it will run, including many different types of equipment with motors although not specifically central heating. Obviously the solenoids will be inductive but the overall PF is not too disastrous (my meter says it's about 0.8).
So what is going on? Anyone come across similar problems? Or got any ideas?