Main Power Switch on or off when using shore power?

Keithw · 09-05-2019, 10:49 AM

Sorry if this has been discussed before but I have a question regarding my Raptor and if I should have the master power switch on or off when using shore power. I have read all the info online and yea I get it that it charges my battery and it will be a backup if shore power goes out. My question is when that switch is left on it always runs a fan which woke me up the other night. Not loud but you can hear it run. Then I turned the main power switch off and the fan went out. Everything still seems to work either way. Is this normal or do I have another problem? 2011 300MP Raptor toyhauler.
Thanks,
Keith

Customer1 · 09-05-2019, 11:43 AM

By "main power switch" do you mean what is normally called the battery disconnect?

If so the only time the battery switch should be open (off) is when in storage. You may have heard a fan in the converter as it was charging the batteries. The fan should not run continuously and should shut down after batteries are charged.

travelin texans · 09-05-2019, 11:45 AM

Not sure of the switch you're referring to...
If it's the battery disconnect, with it off nothing should work & the battery will go dead in a few days.
If it's the breaker to your converter, everything should work til the battery is dead, which could be rather quickly.
If you're using the RV not sure why you'd need to/want to turn off either. Once the battery is dead you'll lose all lighting, furnace, fridge, water heater + slides, levelers & awnings won't work.
If storing the RV you're best option is to disconnect either the + or - (or both) battery cable rather than use the disconnect.

Keithw · 09-05-2019, 11:50 AM

Yes, I mean the Battery Disconnect. I plugged it in again yesterday and the fan started again so I pushed the switch in and the fan quit. All seems to be working otherwise. Just don't know why the fan seems to run all the time? Any ideas on what to check? I mostly run on battery and generator. Seldom with shore power other than just getting refrigerator to start up before a trip. Any ideas or seem like should not worry about it?
Thx

Keithw · 09-05-2019, 12:36 PM

The switch I am referring to is right inside the main door on the end of the entertainment center close to the floor. It is a chrome pull switch that is either in or out. It basically shuts off the whole battery power so batteries do not go bad when not using the RV. When dry camping that is where I power up the whole unit. The fan runs when on shore power and switch is on or pulled out.

travelin texans · 09-05-2019, 04:40 PM

Sounds like the cooling fan for the converter which will run when under a load. Some converters may run the fan more than others or yours may be on its way out.
As far as I know the fan should run when on generator power as well if converter is under a load.

**chuckster57** · 09-05-2019, 05:25 PM

I hope your not trying to operate the slides with the battery(s) disconnected. The converter by itself isn’t designed to deliver the power needed to run the slide motors or the hydraulic pump.

ChuckS · 09-06-2019, 05:33 AM

If you want a quieter converter remove the stock WFCO and replace with a Progressive Dynamics converter. The fan will run less and is also much quieter

Keithw · 09-06-2019, 06:35 AM

That is the first I heard of that you need both the battery and the 30 or 50 amp shore power to run the slides. I am kind of new to this but I think I have done it with and without battery. Thoughts?

**JRTJH** · 09-06-2019, 06:44 AM

Quote:

Originally Posted by Keithw

That is the first I heard of that you need both the battery and the 30 or 50 amp shore power to run the slides. I am kind of new to this but I think I have done it with and without battery. Thoughts?

You might want to spend a little time reviewing the FAQ section of the WFCO website: https://wfcoelectronics.com/faq/ There is much more to operating an RV than "plugging it in and cooking a meal before bedtime"...

Operating the slides, landing gear, tongue jack (on some models) can destroy the converter/charger unless a battery is connected...

As for the "fan makes noise and I can't sleep"... The converter/charger produces heat when it converts 120VAC to 12VDC to charge the batteries. That heat shortens the component life. When the fan comes on, it cools the transformer in the converter (during battery charging). It also comes on when more than "somewhere around 5 amps of power consumption" is occurring.

The fan is a protective device built into the converter.

Not leaving your battery connected to the charge circuits will shorten the battery life by drawing it down below the recommended charge level (around 70%). The converter automatically maintains the battery at above 95% charge status, essentially protecting its lifespan.

Disconnecting the battery cutoff switch as a 'regular part of controlling the converter fan" is very likely to damage not only the converter/charger, but probably will shorten the useful life of your battery....

All of that (and much more) is available in the FAQ section and in the description of features on the WFCO website... Easy reading, enlightening information and very useful for any RV'er to know and understand about their travel trailer.

jsmith948 · 09-06-2019, 06:47 AM

Quote:

Originally Posted by Keithw

That is the first I heard of that you need both the battery and the 30 or 50 amp shore power to run the slides. I am kind of new to this but I think I have done it with and without battery. Thoughts?

The slides are 12v. The converter cannot keep up with the amperage draw of the slide/pump motor. At least not for very long. That is why your manual (and the sticker on the switch panel) warn you that a fully charged battery must be connected before using the slides.

Oops - was typing while John was posting.

Keithw · 09-06-2019, 07:11 AM

Ok, back to my original question is it normal to have the converter fan run nonstop when hooked to shore power? My batteries are good and fully charged. The only thing powered is the refrigerator and the LED lights on the three TV's. Thoughts?

**JRTJH** · 09-06-2019, 07:34 AM

Quote:

Originally Posted by Keithw

Ok, back to my original question is it normal to have the converter fan run nonstop when hooked to shore power? My batteries are good and fully charged. The only thing powered is the refrigerator and the LED lights on the three TV's. Thoughts?

Depending on the "hidden current draw" that you don't mention, yes, it's normal for the converter fan to run. If you want to find out what is running that you haven't mentioned, things like the refrigerator control board, TV amplifier system, water heater control board, LPG leak detector, CO monitor, remote control (In Command system), charging circuit for the battery among some of them, then start pulling the 12VDC fuses one at a time. You'll find the "large amp draws" that way. As you pull the fuses, you'll disable things that you may not even realize are drawing power. Replace each fuse after "taking inventory" of what's not running, move to the next fuse and do the same. Not only will you become more familiar with your trailer and "what does what" you'll also become more aware of all the things you never realized are powered up and using battery juice when you're camping.

As you pull the fuses, one (or maybe more than one) will cause the fan to stop running. That's the fuse which controls the "heavy use item" and will help you understand why the fan runs... It's a thermostatically controlled variable speed fan and as you turn 12VDC items on, at around 5 or 6 amps of converter draw, the fan will start slowly and increase the speed as the demand increases.

When you consider that the battery typically draws 15-45 amps (all available spare energy) from the converter/charger when it's being charged, you'll understand that the fan running is a good indicator that the battery "needs power". Once the battery is nearly charged, the amperage will automatically decrease and as long as you don't have "too much other stuff turned on" the fan will stop running as the battery goes into "trickle charge status"....

Keithw · 09-06-2019, 07:44 AM

Thanks for all the good info. I will get used to the fan when I am plugged in. I normally dry camp so the unit is really quiet. Always listening for new noises. Guess that is the Army in me.
Thanks again and have a great weekend!
Keith

Customer1 · 09-06-2019, 04:47 PM

Are you pulling the pin from the breakaway? That will put a good load on the converter.

Keithw · 09-09-2019, 06:58 AM

So run the rig all weekend and the converter fan seemed to run for a long time and then shut off. Seems like it worked fine. The weekend previous it seemed like the fan never shut off. Maybe it was that I just happened to be in the rig every time it was cycling to cool. I am interested what you mean by pulling the in on the breakaway. Could you please explain that. Are you talking about the saftey cable that I unhook from the 5th wheel hitch? I never do anything more than unhook it? Please clarify.
Thx,
Keith

**JRTJH** · 09-09-2019, 07:09 AM

Keith,

Some "noobies" have the mistaken idea that pulling the pin on the breakaway switch (on the fifth wheel pinbox or A-frame on travel trailers) thinking that it will act as a "parking brake" to help secure their trailer when not hitched to the truck.

Pulling that pin applies "full battery power" to the brake magnets (one in each trailer hub) and will draw a significant amperage. If left in the "pulled condition" not only will you discharge your battery in a relatively short time, if connected to shore power, you'll "over-burden" your converter/charger in the power center. That doesn't even address that you're overheating the electro-magnets and could either burn them up or melt the wiring under the trailer from the break-away switch to the axle hubs......

I think customer1 was asking if, by chance, you might be pulling the break-away pin when unhitching. If you were, that would explain the "significantly increased draw" on the converter and would likely be the reason for the cooling fan to run all the time.

Keithw · 09-09-2019, 07:22 AM

Thanks for the clarification. I am new the 5th wheeler but that idea never crossed my mind. Thanks for the info!

Customer1 · 09-09-2019, 05:34 PM

Quote:

Originally Posted by JRTJH

Keith,

Some "noobies" have the mistaken idea that pulling the pin on the breakaway switch (on the fifth wheel pinbox or A-frame on travel trailers) thinking that it will act as a "parking brake" to help secure their trailer when not hitched to the truck.

Pulling that pin applies "full battery power" to the brake magnets (one in each trailer hub) and will draw a significant amperage. If left in the "pulled condition" not only will you discharge your battery in a relatively short time, if connected to shore power, you'll "over-burden" your converter/charger in the power center. That doesn't even address that you're overheating the electro-magnets and could either burn them up or melt the wiring under the trailer from the break-away switch to the axle hubs......

I think customer1 was asking if, by chance, you might be pulling the break-away pin when unhitching. If you were, that would explain the "significantly increased draw" on the converter and would likely be the reason for the cooling fan to run all the time.

What he said.

Callie Spillane · 09-12-2019, 10:55 AM

The problem could be your battery and or the connections to the battery are corroded so the power supply is working hard to charge a bad battery. If you disconnect the plus side and isolate it then turn on the power supply see if the fan runs? If not its the battery. I use a separate battery charger a few times a summer to get a good charge on the battery. Unplug from shore power disconnect the battery from the trailer and isolate the battery wires then charge the battery over night then put it back together.

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