1. External Power 2. Inverter

[ue40hole5]

We recently acquired a 1997 Fleetwood Tioga Montera 24'.

Questions (2):

1. Does everything, including the 12v stuff (lights, water pump, etc.) run off external power (shore power) when it in connected? And, should the coach battery be charging when plugged into external power?

2. A former owner installed a household refrigerator that only runs when connected to external power. I was investigating getting a 2 or 3 way refrigerator, very expensive. It was suggested that I might get an inverter and at least run it on 12v when going down the road charging the battery. Does this make sense?

 

[Larry N.]

1. The items that use 120V AC power will run off the shore power (microwave, etc.), but the stuff that runs from 12V DC still runs off the batteries/converter, and the house batteries should be charging when you're plugged in to the shore.

2. Indeed it does. Many coaches today come with a residential fridge and an inverter to feed it when on battery power. You'll need the inverter connected directly to the batteries, in most cases, since you'll need something bigger and more powerful than those they advertise for a lighter plug. And, unless your battery capacity is rather small, you can also run it for a while when parked, not just when going down the road. Details depend on exactly how your rig is configured.

 

[Isaac-1]

1, If everything is working right, your Converter should handle recharging your batteries as well as supplying power to all the 12V loads (lights, control board for water heater, furnace blower etc., though if it is still the original converter you may want to upgrade to a modern 3 or 4 stage unit which will extend the life of your deep cycle batteries, such as ones that are built by Progressive Dynamics.  This does depend on the model of converter installed in your coach, being a 1997 it may already be a 3 stage unit, though that is a dice roll.

2,You will need some hefty deep cycle batteries to power a residential refrigerator for any length of time on inverter power, something that may not be within your cargo carrying capacity (weight limit) on a class C, unless you opt for very expensive lithium ion batteries.

 

[grashley]

The RV has two (almost) independent power systems.  Three is you count the chassis (truck) system.  The battery (12 V system) supplies power for almost all lights, slides, steps, levelers, furnace and control circuits for the water heater.  When 120 V is supplied from shore power or a generator, it will run A/C, microwave, fridge and all 120 V outlets.  It also powers the converter, which charges the battery, which powers the 12 V systems.  One can debate if the 12 V comes from the battery, which is then charged, or if the converter provides the 12 V power, or some of both.
Yes, the battery should be charging when on shore power.  It should also be receiving some charge while driving, from the truck alternator.

Residential fridge is preferred by many who do not boon dock.  They will hold temperature for some time while traveling IF the door is NOT opened.  An inverter can power the fridge while traveling or when stopped without shore power.  It takes 12 VDC power from the battery and inverts to 120 VAC.  Some inverters have built in ATS or Automatic Transfer Switch. Both 12VDC and 120VAC are wired into the inverter.  When 120V is present, it passes through the inverter to power whatever is connected to it.  When 120V is absent, the ATS switches to the inverter  mode (12VDC --> 120VAC) supplying power to the output.  The amount of 120V power available from the converter is dependent entirely on how much battery power is available.

 

[IBTripping]

Gary the RV Wizard has been schooling me on my converter-charger in my 1996 TT. He also schooled me on inverters so I can install a residential refrigerator. I found that I need to upgrade my obsolete converter-charger because it has a lousy charging function that will shorten the life of my batteries. Not as big a deal to upgrade as I first thought.

As for installing an inverter for the residential refrigerator and my CPAP, that also is not going to be as difficult as I thought. Here is a link to our current discussion: http://www.rvforum.net/SMF_forum/index.php/topic,118895.msg1080447.html#msg1080447

Also, I found that spending some time researching about batteries and battery management in the Library section of the forum gave me a much better understanding the dc (battery) electrical system in my TT. I also did a key word search on the forum discussions to also get some good info.

FYI - The reasons I decided to install a residential refrigerator is that an RV refrig does not always cool and freeze as well as a residential, the RV refrig needs to be defrosted, and the RV refrig uses more electricity than a residential. You've already found out that an RV refrig is very expensive.

I suggest you open the converter charger panel and get the brand and model number. Then do a google search of that brand & model to see is it provides good charging management for your batteries. Deep cycle RV batteries are expensive, but will last a long time if charged and maintained properly.

 

[John From Detroit]

Re the cost.. Last time I priced RESIDENTIAL fridges I needed to change underwear as it were (Expensive applies to those as well)

Defrosting.. I think there may be a way to control that.. I put two 4" fans one is normal computer type fan the other is much slower turning (not nearly the air flow) the high side is frost free. the low side is about 1/2 what it would normally be this far down teh defrost cycle. (Been a long time since derfrosting)

THere is a dual or triple fan product that mounts to the top of the fridge  includes lights. it costs about 100 buck but I'm guessing it will make the fridge part frost free.. The freezer I'll have to defrost a couple times a year but no problem there way easier than defrosting the larger fridge.

 

[Larry N.]

Re the cost.. Last time I priced RESIDENTIAL fridges I needed to change underwear as it were (Expensive applies to those as well)

Yes, if you want all the fancy electronics, a residential fridge can be pricy. But you can also get one for under $1000 if you don't need all the goodies. Sears (for example) even has a French door model listed at $999.99. And here's a fridge for $597.60, though less fancy.

 

[docj]

Re the cost.. Last time I priced RESIDENTIAL fridges I needed to change underwear as it were (Expensive applies to those as well)

The Samsung RF18, counter depth 30" French Door fridge which is popular for RVs is ~$1350 (AJ Madison).

The Norcold 1210LR, which used to be popular in high end MH's and fifth wheels, is currently on sale for $3018 at PPL.

From those prices it appears that you could buy a Samsung PLUS a Magnum pure sine wave inverter/converter for the cost of the Norcold.  (And you wouldn't have to buy a fire suppression system to go with the Norcold!  ;D)

 

[Gary RV_Wizard]

Most RV fridges are 8, 10 or 12 cu ft in size, and you can buy a similar size residential fridge for a fraction of the price of an RV fridge.  An 8 cu ft residential runs around $250, a 10 cu ft around $450, and a 12 cu ft around $500.