Foretravel Owners' Forum For owners and Fans of Foretravel Motorcoaches September 10, 2025 ...

I have the inverter in the bay with the compressor.

The INVERTER uses battery power to provide 110V power to the coach when it is not plugged into shore power or when the generator is not running.  When using the inverter, you must monitor the voltage on your "combined" battery bank so that it does not drop too low.

The biggest problem with having all three of your batteries tied together is that it is possible for them to be depleted to a point where you cannot start the big engine or the generator.  To avoid this situation, your coach was originally equipped with the battery isolator which separated the two battery circuits.

It is not "wrong" to have all three batteries tied together, but it requires additional vigilance on the part of the owner.  If your coach will be plugged into shore power most of the time, it probably won't be a problem.

That coach originally had 2 house batteries 8D and 1 engine battery 8D in the same compartment. Someone apparently tied them all together. Not a good idea as that is a single bank so if one goes down they will all be down. I would figure out how it was originally wired and then correct the wiring. There should be a battery isolator located on the frame behind the left rear wheel accessible through the small door behind the left rear wheel.

So in reality the inverter would be seldom used maybe for lights in an emergency.

I removed the OEM Taytronics MSW inverter a few months ago and installed my old Trace inverter and a new pure sine wave inverter. I did have to modify the wiring at the changeover box because of the Taytronics switch. Saying that because you can't just install a new inverter where the old one was and have it work correctly.

The OEM inverter worked flawlessly since the coach was built but used a lot of juice at idle. As soon as it was powered on, the voltmeter took a dive. The new sine wave inverter goes just to the microwave and the big wall TV with the Trace powering everything else. Both are much more efficient. The Trace surprisingly so since I purchased it in 1989. It pulses ever second to see if anything is on and then turns itself on. Even when on. it does not draw much current. I still have more wiring to do.

REMOTE SWITCH FOR INVERTERS WITHOUT A PORT: If you buy or have most any inverter without a remote switch, I found a trick to run a telephone type wire and turn the inverter on or off from most anywhere in the coach. It even works on the '89 Trace inverter. Your inverter does NOT have to have a port for a plug but you will need to pull the cover to connect a set of wires to the on/off switch. I can post a DIY for inverters without a port for a remote switch. With a port, it's a no brainer plug and play.

Pierce

What size inverter should I look for?

Then back to the FT.

Before you spend a bunch of money (and time and effort) replacing your old inverter, it would be a good idea to think about how you will use your coach.  With your coach in stock factory configuration, you will only NEED to use your inverter if you do not have a shore power hookup AND you do not want to run the generator.  How often will you be in that situation?

If, when traveling, you spend most or all nights at campgrounds with 30 or 50 amp shore power connections, then you won't need a new inverter.  If you tend to camp mostly in the HOT summer months, and you don't have shore power hookups, you will be running your generator to power the roof air conditioners.  In that case, you won't need to use the inverter.

The most likely time that you would want the inverter is when boondocking in cool weather conditions where the roof air is not needed.  THAT is when you will appreciate a good inverter, AND a large capacity battery bank.  Using the inverter to power ac loads avoids having to listen to the irritating (to you and other campers) racket made by the generator.  Of course, there is no free lunch.  If you deplete your batteries running the inverter, you will eventually need to recharge them.  If you are driving every day, you can let the alternator do the recharge work.  If camped in one spot for multiple days, you'll probably need to run the generator for several hours each day, but you can do it in the middle of the day when the noise will be less annoying to everyone.

Of course, as Pierce suggests, you can always add solar to supplement the generator, but that is another subject entirely.

All I'm saying is think about how you will use your coach, come up with a long-term plan, and then spend your upgrade money where it will do you the most good.

Many of the good modern inverters also have a built in multi-stage battery charger. If you are considering upgrading the existing converter/charger (which you should do because they are battery cookers) and are also wanting a pure sine wave inverter (many modern electronics require that) then you have the option of replacing those two units with a single inverter/charger...I have one and it works perfectly...this is my third project vehicle that I've used AIMS inverter chargers on and haven't had a single failure..

I did order a smart charge adapter...

Wait until you get the Charge Wizard - try it - see how it works.  The charger you have will probably work just fine.

Are your 3 new batteries AGM or are they traditional "flooded" wet cells (the kind with removable caps so you can add water)?

They are old style flooded with removable caps.

Your coach came originally with a battery box, the lower portion in your picture has deteriorated somewhat. Do you still have the top section? When covered the top portion has a vent hole which a 2" pipe  attaches to vent wet cell batteries. Pretty easy to rebuild bottom section with fiberglass but will have to be taken out to repair.

Was it hard to combine all wiring into one location? Or did you have to?

.......The one bit of rewiring I did do was to put the refrigerator on one of the circuits that the inverter supplies (I have no idea why Foretravel didn't do that) as I always use the inverter to run my fridge while driving (unless I have the generator fired up to run roof air cond.).