Hot Water Heater?

acritzer wrote:
Any suggestions would be appreciated.

Start with providing the make / model of water heater you have, whether it's pilot light or DSI. Pretty hard to offer suggestions when we have no idea what you have. ;)

It's a suburban SW6 DE. I can't light it manually. I can cover up the gas line and it has no effect on the hissing. I don't think the electrical spark is working, but I'm not sure why I still wouldn't be able to light manually. No idea how it would have heated up some water. There does not appear to be a pilot light at all.

acritzer wrote:
It's a suburban SW6 DE.

Which means it's a DSI (Direct Spark Ignition) water heater with a 120 vac electric heating element, not a manual light pilot flame heater. Any DSI water heater needs 12 vdc and propane gas to run in the gas mode - got both? :@

I'd suggest you first read through the Installation and Owners Manual ... if you don't have one you can download it here.

Propane works inside so I'd assume that's good. I'm plugged into house elec so I'd assume that's good. No breakers are blown, or fuses, from what I can tell.

Do you have a good charged up battery installed. The DSI is a 12v system.

My battery is pretty well dead, but I'm plugged in now so it shouldn't matter, right? All my interior lights work, I think they're 12v

acritzer wrote:
Propane works inside so I'd assume that's good....

Maybe, maybe not. Spiders love to plug up the propane orifice for some reason - they're attracted to the propane odor? Your manual should show how to clean the gas jet.

acritzer wrote:
My battery is pretty well dead, but I'm plugged in now so it shouldn't matter, right?

Wrong.

Dead batteries suck up the Amps when charging, causing low voltage throughout the camper until they're up to snuff. Lights don't give a hoot because they're just dumb resistance devices, but the smart electronics in your water heater care very much if the voltage is low, in that they will not work until they see a minimum voltage.

Let the batteries charge up and try again later.

If you have a completely dead battery draining the system you probably have less than 12 volts even when plugged in to shore power. With less than 12 volts many 12 volt systems will not operate. You have some warm water from the 120 volt element. Disconnect the battery and try to light it with out it connected to the battery. Many convertors will operate all 12 volt systems when plugged in without a battery connected. With a dead battery connected, even while it is trickle charging your pulling your volts well bellow 12 volts.

Not sure about "hissing" but a propane water heater has a large visible flame - go outside and see what the flame looks like. If no flame then - see if you can smell gas. If no flame and you can smell gas then you might need to remove the spark assembly - clean the probes with emery board and make sure they are within correct range for ignition. You just need to remove a screw or two - not hard.