Community Forums

wiggledbits · 10-25-2022, 11:12 AM

Is it normal or common to need to have the ignition on to have power to appliances even when plugged into 120? I can understand it for lights that draw from the battery. Maybe I'm not thinking this through.

wolfe10 · 10-25-2022, 11:41 AM

Please tell us what year and coach make/model you have.

But, yes quick answer for most RV's is NO you don't need the ignition on to power 120 VAC appliances assuming everything is working as it should.

Unplanned Tourist · 10-25-2022, 11:46 AM

No. Your house battery system will power your lights. The charger/converter will keep the house batteries charged up while hooked to shore power. (120 Volts AC)

twinboat · 10-25-2022, 11:50 AM

You may need the ignition on if your house battery is dead AND your converter/charger is not working.
Turning the ignition on connects chassis battery to house wiring, supplying 12 volts.

Fridge, water heater, air conditioner need 12 volts to power the controls.

wiggledbits · 10-25-2022, 07:42 PM

Quote:

Originally Posted by wiggledbits

Is it normal or common to need to have the ignition on to have power to appliances even when plugged into 120? I can understand it for lights that draw from the battery. Maybe I'm not thinking this through.

It's a 1992 Cobra Seven Seas on E350 chasis. This rig and RVs overall are new to me.

Your answers are what I expected. Right now I only have 1 cabin battery and it nor the motor battery are new and full charged. I did not want to try the converter with just the single batter on a huge draw like a heater.

I will have to go back through checking but yesterday I wanted some heat while working on the inside and though I'd do more than turn on heat to make sure it blew warm. Plugged into an outlet in garage and nada until I turned on the ignition.

Thanks.

Sunrise Camp · 11-03-2022, 05:54 AM

No, you should not need your ignition on to run appliances from 120V shore power. If you run a propane fridge it also needs 12V power from your battery, but not with the ignition turned on.

Johnynorthla · 11-03-2022, 08:53 AM

Don’t you have an Lp furnace? If so run that, but if your not plugged in to shore power, it too requires 12V to operate.

Whenever I’m working in my rig at my home and it’s cold, I throw on my Honeywell 360° heater that I have. It works great, has 2 wattage settings, doesn’t draw too much on low. You should carry one as a back up too. I have 2 electric heaters and I have a small LP portable heater but wife’s afraid of the LP!

It’s true when you turn on your ignition the battery isolation solenoid engages, connecting both house and chassis battery in parallel. It disengages them when cranking your engine and re-engages when running. (If it’s working properly)

twinboat · 11-03-2022, 10:04 AM

You need your converter on to put provide 12 volts for the furnace. That's what converters are for, plus they charge batteries.

Turning on the ignition closes a solenoid that's installed to charge the house battery while the engine is running. If that makes the furnace run, your house battery is dead or not connected.

Mark_K5LXP · 11-03-2022, 12:09 PM

Quote:

I did not want to try the converter with just the single batter on a huge draw like a heater.

Heaters are not a huge draw, nominally 6 to 7 amps to run the blower. Even a light duty RV/marine battery can run a furnace overnight if not longer. A "small" converter is 30 amps or more, so the heater is not going to tax it.

Mark B.
Albuquerque, NM

THenne1713 · 11-04-2022, 08:50 AM

Most all RV appliances use 12vdc for CONTROLS, but it should come from COACH BATTERY vs chassis/ engine battery, so suspect BATTERY SWITCH is OFF, or battery installed backwards and blew FUSES? ALSO check 120VAC CIRCUIT BREAKER feeding the CONVERTER. ALL should work w/ IGN=OFF. Good Luck