First time using the heater in the MH

[Campfire RV]

This past weekend we took a one night trip in the mountains for dry camping. When it began getting really cold I turned on the generator and started the heater which worked great. After a while I decided to turn off the generator and I noticed my heater still worked which was great as well. I woke up around 4am because it was getting cold again in the MH and I kept hearing a clicking noise and I noticed it was coming from the heater so I checked my propane which was still good but my battery had died so I started the engine to charge the battery and the heater worked like a charm again.

Why can the heater work but not A/C without running the generator? I thought they would be the same but obviously I was wrong.

Thanks,
Josh

 

[John From Detroit]

By "Heater" do you mean the RV Furnace? Propane heat?  The blower and controls all run on 12 volt battery power, no 120 volt needed. (Well you do need to charge the batteries from time to time)

Most RV's are designed so they can run the furnace overnight (10pm to 8am) on battery power alone, Some much longer, this assumes you are not sucking power out of the batteries with an inverter or lit up like a shopping mall grand opening.

IF you are talking space heaters,,,,(Plug in heaters) you may have plugged into an inverter powered outlet.. Thiese will suck your batteries down very fast.

 

[Jeff Brown]

A neighbor had this problem with his heater killing the house battery over night.  An upgrade to two 6v Interstate Golf Cart bateries solved the problem.  It's just too many amps drawn for too long on a standard 12v house batery was what the tech told him.  Look at the amp rating on your blower, then the amp/hour rating on your battery and the math should make sense.  Keep in mind several other things are sipping from thouse amp/hours as well with a small amount being lost to the actual wires depending on length and distance. 

We have found that the onboard heater drinks propane as well as battery power.  Sure do love hookups with our electic oscilating heater.

 

[Jammer]

Why can the heater work but not A/C without running the generator? I thought they would be the same but obviously I was wrong.

The heater gets its heat from burning propane, so it only needs electrical power to run the fan, and can run from the battery.  On the other hand, the A/C has to have electricity to run the compressor, and it takes a lot of electricity.

The heater can draw enough power to deplete the battery especially if the battery is in poor condition or is undersized.  4-5 years is the most you can expect from a battery and if they aren't cared for they can fail after the first season.

My truck camper has a heater in it that doesn't require any electricity at all, relying only on convection and using a thermopile generator to run the thermostat and gas solenoid.  Unfortunately that's a design technique that has become passe so we're stuck with batteries in newer rigs.

 

[Campfire RV]

I was using the RV heater and propane. I didn't fully charge the battery before leaving the house because I didn't think I would be using it much for one night and it was still at 75% when we left the house. I turned the generator off around 9pm then noticed the heater not working around 4am when I noticed the battery was dead or nearly dead because I could still turn on the coach lights. When I started the engine the heater came back on with no problem.

Thanks for the explanations everyone, at least now I know I should at least have the battery fully charged before leaving the house even for a one nighter.

 

[dave61]

Josh, if you plan this type of use regularly you should consider a second house battery. Deep discharge of the battery will shorten its life, plus who wants to worry about it.

 

[ironrat]

I was using the RV heater and propane. I didn't fully charge the battery before leaving the house because I didn't think I would be using it much for one night and it was still at 75% when we left the house. I turned the generator off around 9pm then noticed the heater not working around 4am when I noticed the battery was dead or nearly dead because I could still turn on the coach lights. When I started the engine the heater came back on with no problem.

Thanks for the explanations everyone, at least now I know I should at least have the battery fully charged before leaving the house even for a one nighter.

I may have missed something here. But you say you didn't charge the battery before leaving, well it should be being charged by the alternator when you were driving including the house battery's as well. The same should be happening when you are running your generator.

 

[John From Detroit]

Regarding a battery at 75%,,, if you have a single 12 volt Marine/Deep cycle battery, you really should maintain it at a higher charge level,  Marine/Deep cycle are starting batteries with lip service to Deep Cycle needs, they really like to be 75% or better.

TRUE deep cycle change that to 50%    Some special and far more expensive types claim they can go far lower... but I tend to disbelive thoe claims as they are made by salesmen and you know how to tell when a salesman is exaggerating the abilities of his product right. (Hint, he is telling you about it).

Many folks go with a pair of GC-2 Golf Car batteries in series, these are six volt batteries but when you put them in series they become a 12 volt battery bank.

230 amp hours

That is more than 3 Group 24, More than 2 Group 29 or 29, Slightly less than 2 Group 31, roughly one 8-D.

And they are TRUE deep cycle batteries.  They do need care and watering however. (Distilled water only) Watered mine... Sunday.