Appliances don't work with shore power

[wicked5ltr]

I went to look at a 92 Terry Resort Model 29S, 29ft today and really want to purchase as the price is right, but I want to verify that the appliances all work first. Problem is, with shore power hooked up and no batteries installed (owner hasn't bought new batt yet) and no propane. The only thing I can get to work is a couple of wall lights and the light inside the microwave. The microwave itself doesn't operate, the fridge doesn't work in either mode, the A/C won't turn on nor does the furnace or water heater. I know the water heater and furnace require propane, but shouldn't the fridge and A/C work with just shore power? I checked all fuses and breakers on the distribution panel and all were good. The owner said his brother in law said he blew the transformer when he connected shore power (which I assume he meant converter) but he also says he brother doesn't know much about this stuff. The distribution panel is a Magnatek RV80 with breakers on the left half and fuses on the right half, is the converter built into this or mounted somewhere else? I looked in the compartment behind it which has lots of room and didn't see anything that resembles a converter. I haven't bought the trailer yet as I wan't to confirm everything operates first, any ideas as to where the converter is, or what the real problem is if it's not this? Thanks, Tim

[wicked5ltr]

I went to look at a 92 Terry Resort Model 29S, 29ft today and really want to purchase as the price is right, but I want to verify that the appliances all work first. Problem is, with shore power hooked up and no batteries installed (owner hasn't bought new batt yet) and no propane. The only thing I can get to work is a couple of wall lights and the light inside the microwave. The microwave itself doesn't operate, the fridge doesn't work in either mode, the A/C won't turn on nor does the furnace or water heater. I know the water heater and furnace require propane, but shouldn't the fridge and A/C work with just shore power? I checked all fuses and breakers on the distribution panel and all were good. The owner said his brother in law said he blew the transformer when he connected shore power (which I assume he meant converter) but he also says he brother doesn't know much about this stuff. The distribution panel is a Magnatek RV80 with breakers on the left half and fuses on the right half, is the converter built into this or mounted somewhere else? I looked in the compartment behind it which has lots of room and didn't see anything that resembles a converter. I haven't bought the trailer yet as I wan't to confirm everything operates first, any ideas as to where the converter is, or what the real problem is if it's not this? Thanks, Tim

[Fulltimer]

You need to know if the wall lites run off the battery or not.(look at the lite bulb) If they do then your 12v circut works. If the lite in the M/W comes on, your Ac circut works. The M/W should work. The A/C should also work(at least the fan) as should the fridge if the 12v is working.Electric should work without porpane. Same with the furnace. It will not heat but it should cycle on. You dont want you water heater to come on unless it is full of water.
You can also try your 12v circut by hooking up your TV cable. Be sure the battery cable in the trailer are not shorting.

[Jeff_in_The_Dalles]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">The owner said his brother in law said he blew the transformer when he connected shore power </div></BLOCKQUOTE>

I wonder if that means that they plugged the unit in to a mis-wired RV socket...

People have been known to accidentially wire those to 220v, and then blow up the converter, the 110v element on the fridge, the microwave...

Also, the computer on some fridges are sensitive to clean 12v power, so if the converter on that unit produces some buzz or unsteady voltage (without the battery to kind of attenuate) that could cause problems.

With only the light working on the microwave, though, and his saying something about having blown the converter when hooking up to shore power, I'd suspect it got plugged in to 220...

[wicked5ltr]

The owners just inherited it from her parents, and when the brother in law plugged it in to their house for the first time (110) is when it supposedly blew something. Hopefully they'll get batts and maybe a new converter if that's the problem and everything will start working properly, could a bad converter be the whole problem? Thanks, Tim

[DNR250]

This sounds like a Handyman Special. We see units like this all the time and when we give the repair estimate to the customer, they realize it wasn't such a good deal. If the microwave doesn't work, then it may be damaged beyond repair. As mentioned earlier, you should have 12v, but you should have a battery installed. Unless you are able and willing to go though the unit system by system, it may not be such a good deal.
BTW, the converter is probably under the couch.

Another option would be to locate a mobile RV service tech to perform a complete system check (often refered to as a mini prep or presale inspection). It'll cost a few bucks, but at least you'll know what shape the unit is in.
D

[wicked5ltr]

I think I'll ask the owner to at least replace the converter to see how much that fixes, If I only have to replace the micro, then that's fine, but if I have to replace a fridge or furnace, etc. then I'll pass, those are big bucks, unless I can get the owner to subtract the cost of those items for the sale. Thanks for the help, any other suggestions would be great!! Thanks, Tim

[Frank P. Martin]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">The owner said his brother in law said he blew the transformer when he connected shore power (which I assume he meant converter) </div></BLOCKQUOTE>

You say the battery isn't in the trailer. Is it possible that the positive battery wire accidentally either became grounded to the frame or touched the negative battery wire? If this occurred and you plugged into shore power, a short would have occurred. The minimal damage would be blown fuse(s) or tripped breaker(s); the maximum damage would be a fried converter and/or possible damage to any number of appliances that run off the 12v power.

Every microwave I've ever seen in an RV is strictly "house current" AC. Being that you're seeing the light come on inside the microwave (and this should only happen when plugged into shore power unless your rig is equipped with a DC to AC inverter that the microwave's wired into), the microwave itself should work too. If not, I would have to think the microwave is broke. It's obviously not a tripped breaker/blown fuse because the light inside the microwave wouldn't come on if that were the case.

[wicked5ltr]

Well, I went back over there today to look at the converter, sure enough, it was disconnected. The owner had a borrowed battery and propane for temp use. We connected the converter and as soon as he plugged in the cord, I heard a quick faint sizzle sound from the converter and the breaker in the house tripped, and continued to trip after a few reset attempts. We did get the everything 12V/propane to work: fridge, water htr, furnace, lights, water pump. The only thing I can't verify is the A/C, fridge in 110, and the microwave. I can deal with a bad micro, but want working A/C and fridge in 110. Now does it sound like it is most likely only a bad converter (minus the micro)? Thanks, Tim

[450Donn]

Really sounds like you need someone with electrical knowledge to go with you to check things out. You should be able to turn off the breaker for the converter and then if it is bad the 120vac should hold. Then you could test the micro. Unless you have at least 20 amps the ac will probably not run.

[Frank P. Martin]

Tim:

Based on the test results in your posting, this is what I would do to test the A/C and refrigerator on shore power:
<UL TYPE=SQUARE>
<LI> Disconnect the Trailer's battery.
<LI> Disconnect whatever you connected on the converter so there's no AC going into it. If you can disconnect it from the DC side, I'd do that too as this will ensure the failing converter is totally isolated from the electrical system.
<LI> Reconnect the trailer's battery.
<LI> Most RVs have a control panel to check water/waste tank levels and condition of the battery. If this trailer has one, check the battery. I would recommend that the battery be at least 3/4 charged. Most likely, you'll still be OK even if it's less than 3/4. However, the 12v control circuit in some refrigerators (like my Norcold's) can "get finicky" and may not work properly when the voltage is too low.
<LI> Plug in to the shore power. The breaker shouldn't trip unless the converter wasn't disconnected correctly or there's a problem with the wiring somewhere else.
<LI> Try starting the refrigerator on AC and air conditioner. Do these separately if you are plugged into a 20A receptacle [/list]
RVupgrades.com sells converters. Prices vary depending on the amperage of the converter. You can see what they have to offer from this link:

RVupgrades.com -- Converters

Good Luck! Hope you have a winner.

[Ray,IN]

Unless you are getting it for a steal, its time to accept DNR250's suggestion and hire a RV technician to perform a check of everything. Let's see, A/C unit replace= at least $490, frig= at least $1,800, well- you get the theme here. Spend $200 on the RV tech and you may save a couple thousand. Keep in mind, when money is involved, friends and family are often the first to take advantage of you.