Heater keeps going out

[patriotcamper66]

Hi, we just got back from a coastal dry-camping trip, and we had to run the heater at night because it got pretty cold. After about an hour the heater shut off. We weren't allowed to run the generator after 9pm. The heater works fine at campgrounds with an electric hookup or when using the generator. This same issue happened a few months ago, so I bought a new propane regulator, made sure both propane tanks were full, and bought 2 new deep cycle batteries. The trailer is a 2021 Cherokee Grey Wolf. All fuses are fine, and the pilot light stays lit on the furnace. A simultaneous problem to the heater stopping to work is the batteries drop to 8.6 from 13.1 overnight until I start up the generator again in the morning. If anybody has any ideas I'd appreciate the help. Thanks!
Erik

 

[RayIN]

Welcome to the rvforum.net discussion forums!

The LP furnace has a low voltage limit listed on the nameplate, your battery voltage dropped below it's safe DC voltage limits. The solution, use less battery power before going to bed.
It has nothing to do with LP supply, fan speed is the main factor.
Your LP furnace does not have a pilot-light, it's electronic ignition only.
You might find this watts draw table interesting: List of Electric Appliances & Wattage Usage Chart (2021 UPDATE)

 

[Laura & Charles]

What Ray said^^^
Get your batteries fully charged up til quiet hour. Set water heater and fridge to propane. If your lights are incandescent, swap at least some of them to LEDs and use those after quiet time. If you use CPAP, turn off the heater/humidifier. There’s no reason a new pair of deep cycle batteries shouldn’t run a furnace overnight unless they’ve been damaged.

 

[Seilerbird]

Heating the entire RV is a massive waste of energy. I only use an electric blanket at night. Much more efficient.

 

[John From Detroit]

There is nothing wrong with the furnace 8.5 volts will not run it it can not move air fast enough so it protects the heat exchanger by not lighting.
More battery or less load on them or a small inverter generator (Say a 1000 or 1200 depending on the converter) Running JUST the converter may help.

Small inverter generators like Honda or Yahama are rather silent.

 

[patriotcamper66]

Welcome to the rvforum.net discussion forums!

The LP furnace has a low voltage limit listed on the nameplate, your battery voltage dropped below it's safe DC voltage limits. The solution, use less battery power before going to bed.
It has nothing to do with LP supply, fan speed is the main factor.
Your LP furnace does not have a pilot-light, it's electronic ignition only.
You might find this watts draw table interesting: List of Electric Appliances & Wattage Usage Chart (2021 UPDATE)

Thank you Ray

 

[Kirk]

the pilot light stays lit on the furnace.

What furnace do you have that has a pilot light? Most RV furnaces today are direct spark ignition(DSI) and have no pilot light. If you just turn your furnace on and off with the thermostat, you don't have one either.

A simultaneous problem to the heater stopping to work is the batteries drop to 8.6 from 13.1 overnight

An RV furnace is designed to operate with a voltage between 14V and 10.5V. Since the blower provides combustion air as well as inside heating air, there is what is called a sail switch that is closed by air movement. A direct current (DC) motor varies in speed, depending on what the supply voltage is. As the battery is discharged the voltage supplied drops and at some point below 11V the blower motor is slow enough that it no longer closes that sail switch so the propane to the furnace is turned off and heat stops. It is a safety device to insure that the propane is off when there is too little combustion air. Your furnace is doing what it is supposed to do to keep you safe. The problem that you have is that your battery is dyeing too quickly.

 

[patriotcamper66]

Welcome to the rvforum.net discussion forums!

The LP furnace has a low voltage limit listed on the nameplate, your battery voltage dropped below it's safe DC voltage limits. The solution, use less battery power before going to bed.
It has nothing to do with LP supply, fan speed is the main factor.
Your LP furnace does not have a pilot-light, it's electronic ignition only.
You might find this watts draw table interesting: List of Electric Appliances & Wattage Usage Chart (2021 UPDATE)

Thank you

What furnace do you have that has a pilot light? Most RV furnaces today are direct spark ignition(DSI) and have no pilot light. If you just turn your furnace on and off with the thermostat, you don't have one either.

An RV furnace is designed to operate with a voltage between 14V and 10.5V. Since the blower provides combustion air as well as inside heating air, there is what is called a sail switch that is closed by air movement. A direct current (DC) motor varies in speed, depending on what the supply voltage is. As the battery is discharged the voltage supplied drops and at some point below 11V the blower motor is slow enough that it no longer closes that sail switch so the propane to the furnace is turned off and heat stops. It is a safety device to insure that the propane is off when there is too little combustion air. Your furnace is doing what it is supposed to do to keep you safe. The problem that you have is that your battery is dyeing too quickly.

Yeah, that's the part I don't understand. We turn off everything and unplug everything that draws power before we go to bed. I'm wondering if there's some sort of unknown draw on the batteries. Also when we store the trailer I put a trickle charger on the batteries.

 

[Kirk]

Have you checked the electrolyte levels in the battery cells? Low levels will cause it to hold less power and in time damage the battery. After 3 years the batteries could be needing to be replaced.

 

[patriotcamper66]

The batteries are only a year old. I think I'll return them to Napa for an exchange even though they're only a year old. Thanks!

 

[John From Detroit]

The batteries are only a year old. I think I'll return them to Napa for an exchange even though they're only a year old. Thanks!

What size/type are they. Many people. You might consider a different type of battery. Or more battery.

 

[gwinger]

The batteries are only a year old. I think I'll return them to Napa for an exchange even though they're only a year old. Thanks!

Napa will probably do a load test on them before replacing them.
FLA batteries need to be checked frequently for water level. AGM's no.
If the batteries are used with low water level, they will not hold a charge for very long. The electrolyte must cover the plates in the battery at all times. The 13.1 volts you measured be be only a surface charge. Any load on the batteries will drop that quickly.