Proper way to Jump Start discussion.

[Kevin Clark]

We’ve been remodeling a new to us 2003 Windsor. the coach has been sitting at someone else’s house for the past month while the cabinets have been getting painted.

I went to start the coach, and both the chassis and the house batteries are completely dead. The person doing the work must have turned something on and drained it.

How should I go about getting this thing started again?

I did plug the coach in but the inverter did not come on. A couple of the 110 V systems inside came on like the microwave but none of the 12 V systems. Is this because the house batteries are so thoroughly drained it’s going to take a while before they will come on?

I did not have any tools with me, so we have to go back tomorrow to get the coach running. I did leave the coach plugged in.

All systems were working when it was parked last month. Lesson learned, use the disconnect switch next time!

[timaz996]

You can jump start the chassis battery but you most likely will have to let your car run at fast idle connected to the chassis battery for a while before you try it. 

[vito.a]

Is it plugged into a 50 amp RV outlet? 

If not, the best method would be to remove the chassis batteries and have them charged and tested.   

Then hopefully you can get your generator started and the inverter online to charge the house batteries.  Depending on how your generator is wired (house or chassis battery) you may have to use the boost switch next to the driver.  

Good luck!

 

[Kevin Clark]

2 hours ago, timaz996 said:

You can jump start the chassis battery but you most likely will have to let your car run at fast idle connected to the chassis battery for a while before you try it. 

Is the chassis battery the one in the compartment next to the water heater? That has to be opened by removing the screw at the bottom?

I have a 3/4 diesel. I was planning to jump it from that if I can do it without damaging anything.

2 hours ago, vito.a said:

Is it plugged into a 50 amp RV outlet? 

If not, the best method would be to remove the chassis batteries and have them charged and tested.   

Then hopefully you can get your generator started and the inverter online to charge the house batteries.  Depending on how your generator is wired (house or chassis battery) you may have to use the boost switch next to the driver.  

Good luck!

 

It is not.  It's curbside at someone else's house. Only 15-amp available.

[vito.a]

With it only plugged into a 15 amp outlet I doubt you'll get it started. 

You could hook your truck up with jumper cables and try charging for a couple of hours.  But you would still be better off trying to start the generator first.  The generator will provide full power to the entire system and allow your inverter to charge your house batteries. 

The problem here is the inverter charges the house batteries first.  Then after the house batteries reach a preset voltage, it will charge the chassis batteries.  

[Kevin Clark]

Thanks, this is helpful info.  I thought about hooking a battery charger directly to the batteries for a more efficient charge.

[Jdw12345]

How old are the batteries? If they are close to being replaced I wouldn’t spend any time trying to charge them, I’d just replace them with new and get the coach back home and then proceed accordingly. You could also remove the batteries from you pickup and use them provided you have wheels to do so. JMO.

[Kevin Clark]

2 minutes ago, Jdw12345 said:

How old are the batteries? If they are close to being replaced I wouldn’t spend any time trying to charge them, I’d just replace them with new and get the coach back home and then proceed accordingly. You could also remove the batteries from you pickup and use them provided you have wheels to do so. JMO.

Batteries were new in July 2023.

[Craggar]

If you have a good set of booster cables you should be able to jump it with your truck, just let them charge for 15 or 20 mins first. I have jumped 930 loaders with my pickup a few times.

[Ivylog]

Need to jump to the 2 engine batteries for 10+ minutes or connect a 10 amp charger to them overnight. Once the engine is running the alternator should start charging the house batteries and once they get above 11.8 V the inverter/charger should start charging them.

Edited April 1 by Ivylog

[Tom Cherry]

My recommendation….  Jump Start Genny.  Then hook up fhe Chassis….let the Genny via the Inverter Charger do the rest….you can also run the engine and supplement.  Be AWARE….follow the protocols…. It is DANGEROUS, as in a stray spike….to just “Jump ‘Er OFF”. Here is the recommended procedure.

NOW…this is based on suspecting (knowing) that the Windsor has the Genny on the House….

Turn OFF both banks.  Hook up a normal set of Automotive cables to the vehicle….idling will be fine.  You are starting a SMALL engine….not the main engine.

Hook up the cables to the House.  Crank the genny.  Let it run for maybe 20 minutes….that will more than restore a cranking charge to the House. OK…inverter is charging the House….

Remove (quickly) the Negative jumper….vehicle or MH….whichever is easier.  Squeeze and disconnect. Remember the inverter should be pumping out maybe 100 Amps….to the House bank. 

NOW….remember the Positive is still hooked up.  Remove the Positive from the Vehicle.  Put it on the chassis bank. You ONLY need one jumper now…as the grounds or negative are bonded. 

NOW….turn on the Chassis BANK.  The Inverter is NOW (regardless of the BIRD or dual charging system) charging both banks.  That is GREAT.  Let that run for maybe 30 minutes.  That will reatore the Surface Charge on the Chassis….  

NOW….crank the engine.  If there is hesitation….STOP.  Don’t drain it.  ODDS ARE….VROOM.  

NOW….you can do nothing except let it run.  Odds are….within an hour….both banks will be back … enough to reatart.  I personally would STOP the engine.  Turn OFF the Chassis….and the  disconnect from the Chassis….put the end on the ground.  Turn on the Chassis…..fire that sucker up.  Let it run for maybe 15 minutes….

NOW….depends on your situaion.  If you have 50 Amp service….Turn OFF the Engine.  Turn off the disconnect.  Hook BACK up the Jumper between the two banks….Chassis Battery ON.  The Genny or your shore will recharge BOTH ( the Jumper is like a TEMPORARY BOOST.  Overnight…..all will be well.

The main thing is to ISOLATE each bank….by turning OFF a bank ar the disconnect switch. That prevents a stray current…or arcing.  

This will accomplish the goal….get both banks recharged….and no need to pull or run temporary chargers.  Since you do NOT know how low or how “Dead” a bsnk it, putting a charger….one that is NOT a 3 phase….is ill advised.  If the batteries were just barely down and you keep pumping in juice…you can drop or lower the electrolyte level.  PROBABLY should have refilled the House Bank at the beginning.

Safer and also protects the MH.

 

 

[Benjamin]

I'm guessing the inverter did not come on because it's controls work off 12V.  So I'd put the jumper cables, or a battery charger on the house batteries until the inverter comes on, then plug it in and remove the jumper cables, then see if you're getting charging voltage from the inverter.  May need to use the positive jumper cable between house and chassis banks if the chassis is not charged automatically. 

[Kevin Clark]

8 hours ago, Benjamin said:

I'm guessing the inverter did not come on because it's controls work off 12V.  So I'd put the jumper cables, or a battery charger on the house batteries until the inverter comes on, then plug it in and remove the jumper cables, then see if you're getting charging voltage from the inverter.  May need to use the positive jumper cable between house and chassis banks if the chassis is not charged automatically. 

Very helpful info, thanks!