2012 21UDS. First weekend out with camper I hit the switch and heard the hot water tried to ignite. It failed and I realized it was probably due to me not turning on the valve to fill it with water. I turned off switch and didn’t mess with it since we were across from the bath house. I’m out this weekend. Tank is full of water. When I hit switch I get nothing. No gas smell. No clicking. Fuses at panel look ok. Anything else I can check with limited tools?