12 volt disconnect solenoid

Just got back from RV I turned on the lights,TV,water pump etc after 15 minutes went out and checked the solenoid,it was cool to the touch . So I guess I'm good now for the next 2 years.

I agree with STLNLUV. You can always use a larger AMP rated one. They make them is a lot of sizes for heavy equipment.

I believe in some cases the cycle from heat to cool etc causes moist air to be drawn inside and there it condenses. I actually proved this on one of mine. After replacing it the new one was mounted inverted to the original and no more problems. I do know for a fact that some relays must not be mounted inverted under the hood of vehicles that are subject to splashing etc. I found many over the years full of water.

With that said it is probably a good idea on some models to change them out just like an oil filter on a planned schedule. Every two to three years would assure a proper operating unit.

It could be a problem if the coach batteries are deeply discharged and the chassis batteries are not. When you start the coach the batteries are bussed together by this solenoid. In this case a lot of current would be passing through the relay.

Im still trying to figure out where mine is

It was hot not warm when I changed it out.

I would be testing the relay without the circuit board in the circuit to determine whether it is the relay or the circuit board.
When it has failed, is there any loud click when you energize it? The contacts rarely fail. It is more often to be the coil, connections or in your case the circuit board.
You could try applying 12 volts DC to the small post where the white wire connects in my link.
You should have 12 volts positive on the red wire to the circuit board, and either 12 volts minus or plus on the white wire terminal when switch is operated.
KIB relay

In addition to moisture, the current rating should be checked. Over current condition will cause them to overheat. Check the temperature of the solenoid while using a several items in the coach. If it is HOT (warm is OK) it most probably is under rated.

It's a KIB LR 9806f disconnect latching relay

Internal corrosion.
What is make and model of the battery disconnect relay?