Okay, so this isn't specific to a conversion, but it is, in fact, happening in my bus. I have a gas residential stove top with electronic spark. The refrigerator and the stove top are in the same outlet. Every time the refrigerator starts one burner on the stove sparks. So, about every 10 - 20 minutes we hear this single snap from the stove.
We're plugged into 20 amp pole power and everything is functioning just fine. We don't run through an inverter for this.
Ideas?
It sounds to me like you got your hot and neutral backwards on the stove's wiring.
Did you spill anything near the stove controls recently? If we spill something on the counter and one of the burner controls gets wet we get exactly the behaviour you are describing. It can clear up quickly or sometimes it takes days to go away. I've tried spraying WD40 in around the controls with varying degrees of success. If it gets too annoying I generally unplug the stove, light it manually for a few days and when I plug it back in everything is back to normal.
Dave try plugging one of them into a power cord or other outlet to see if it has a different outcome.
It might be a power surge or lack of when both are drawing to many amps from same outlet.
Dave5Cs