Question about Suburban SW6DE water heater...

My neighbor has this water heater and can't get it to work. It's a new trailer for her, on line info says it works on both gas and electric but looked in literally every nook and cranny in her trailer today, inside cupboards...and there is no water heater gas switch. Could some of these heaters only work on gas even though it says they should work on either? There is just an on-off switch on the water heater and it doesn't do any clicking as it normally would trying to ignite when you turn it on. I turned it off for several seconds then back on and still, nothing. There doesn't seem to be anything sticking out to push where the reset button is. It's covered with rubber There is hard ring under it but nothing sticking out from the middle of it, and it won't budge.

Anyone who has any knowledge of this model who may know more...any help would be appreciated.

Also, how long does it generally take the coils on a Dometic fridge to warm up once you plug it in?

Thanks...