2007 Thor Mandalay electrical problem

[djcobraman427]

New member here, Hi to everyone.  Now, my problem:  I lost all of the 115Vt power in the cabin.  I had just had an issue with a defective circuit breaker and while waiting for the replacement, I went out today and found the cabin lights and water pump weren't working.  They worked yesterday, not today.  I checked all of the fuses and breakers in the cabin and everything was fine.  It acts like one of the circuit breakers in the battery box had blown.  But they seem to be OK.

The coach was in out storage building, with a surge protector installed, and hooked to 110 volt.  I am not reading any shore voltage above the door at the remote control to the power inverter.  So, am I missing a breaker somewhere along the way.  There are 3 in the battery box, the one that blew first was for the computer leveling system, and it would not reset.  The other 2 seem to be fine.

I'm wondering if there is something wrong with the storage building electrical.  But shouldn't the 50 amp surge protector save the breakers?  I had one other issue where the storage building power kicked off and drained my batteries.  Normally, when I am out on the road, everything has been fine.

What should I be looking for.  Confused in Wilbur, Oregon.

 

[John From Detroit]

Well you said you have a surge protector plugged in, Is it one with an LED or LCD display that tells you voltage and current and other stuff or just indicator lights.  IS IT DARK, or lit up?  (Dark = Building issue, not RV issue)

Then since you said "Coach" I am assuming a Motor home .. If not leave out "Auto Transfer Switch"

IN linier order.. Bad outlet, bad plug (Optional bad outlet on detachable cord, bad inlet) Bad auto transfer switch  main breaker inside RV

Now.. I've found many RVers have a few Screws loose.. Specifically the screws in the assorted plugs, sockets, ASTS and circuit breakers and bus bars.

Since 120 vac is missing, check the "House style" breakers,  12 volt breakers (Found in the battery bay) and fuses are likely not suspect.

For outlets you may have one or more GFCI (Does the Air conditioner fan work,, just fan in storage, anmd the A/C not the fantastic Fan or bathroom fan (Exhauxst fans)  Is the microwave "lit" or dark (open door if needed)

GFCI's often power all the outlets and it can trip for various reasons inclujding a nearby radio transmission.

 

[Gary RV_Wizard]

It sounds as though the problem is either the building power outlet, or possibly the surge protector and/or shore power connection. If no power is getting to, or through, the surge protector, nothing else in the coach is going to work on 120v power. However, 12v (battery) power items should still work unless perhaps the batteries went dead before you noticed the power loss.

What make/model surge protector do you have and does its indicators show?  It could well be that it has detected a power fault and shut off the shore power to protect the coach.

 

[Kevin Means]

I'm not sure I understand exactly where the A/C power is being interrupted, but it's not uncommon at all for the shore-power cord itself to develop problems - especially in the plug. I'd (carefully) start testing the electrical path with a VOM, starting with the power cord.

Your water pump and house lights are obviously D/C items, but from what I can tell, it sounds like they stopped working after the A/C problem started. That might indicate dead house batteries, due to an inoperative charger/converter, which needs A/C power to function. Have you measured the voltage of your batteries?

Kev

 

[djcobraman427]

Surge protector is lit up, saying its working. No problem with the A/c, only the coach lights and plugs, water pump , etc.  Lights for the step and porch lights work.

It acts like there is an interruption from the shore power into the coach.  Since I have had one prior issue with the shore power, I have unhooked that power.  I finally received the circuit breaker for the leveling system and will call the Thor help line tomorrow for their suggestions. 

Thanks everyone, but keep sending your ideas.

 

[John From Detroit]

Ah,now we know. Converter not converting (or inverter not charging if you have one.) those are all 12 volt systems.

Depending on your RV you have either a CONVERTER. this is a device that makes battery voltage out of Shore power (or generator) on an inverter/converter  (This can go both ways)

Now if you have TWO air conditinoers and both work (This is important) this means your shore cords and Auto Transfer switch3es and such are good.  Check your circuit breakers, Epically the mains (YES JUST one of the ganged breakers can be tripped without both being trippee Seen it a few times)  And the one marked CONV

THen you need test equipment after that.. A Voltmeter,  We can talk you thorugh it.

Oh and the make and model of the Converter or Inverter and if you can not find them the make and model of the power distribution panel. (Breaker and fuse box) espicelly if the breaker box and fuse box are the same box.

 

[JoelP]

You might want to check to see if things now not working will work off generator power. That would isolate any issue with the shore cord or plug.

 

[djcobraman427]

OK, update.  I put in a new circuit breaker, as per Thors instructions.  Now, I have coach lights, power to the water pump, but no microwave, ceiling fans, and the computer controlled leveling system still doesn't work.  But, if I power up the generator, I get power to the microwave and the plug ins under the cabinets, which I didn't have without the generator.

This is a Thor Mandalay motor coach with about every option possible.

I'm getting really tired of "camping" when I cant get the electrical to operate correctly.  And I was a missile electronics tech in the Army, so I think I know the basics.  But maybe not the RV basics.  I really hate feeling stupid.

 

[Gary RV_Wizard]

You stated a new circuit breaker for the leveling system, but after replacing it, the leveling system still doesn't work but some other things did begin to work. Either that breaker was not for the levelers, or you inadvertently  fixed something else. And now you have no 120vac power to a/c and microwave,so something else changed as well.  The conflicting information makes it difficult to give meaningful help.

Here are some basics you need to understand: The genset and shore power feed an auto-transfer switch, which connects either shore cord or genset to the load center (breaker box) but never both at the same time. That's you source of 120vac power and 120vac powers a/c, microwave, wall outlets, etc. 120vac also powers an inverter/converter/charger, which in turn produces 12vdc power for things like lighting, water pump, battery charging, and the many control circuit boards in the RV. The inverter will also produce 120vac for selected circuits IF neither shore or genset power is present. The inverter uses battery power when doing that.
120vac power to many items will flow through the inverter, even when the source is shore or genset. That enables the inverter to substitute its 120v for other sources. The inverter has its own circuit breaker and if that trips, you have no power to things like microwave.  The a/c, however, is NOT powered through the inverter, so that should work as long as shore/genset power is active.

The multiple power sources for various things makes troubleshooting complex and requires rigorous technique to isolate what works and what does not.

 

[djcobraman427]

I tried to make it clear that the a/c system was not the issue.  I'm not sure how it got injected into the forum.

I talked to Thor this morning and they said to check the GFI plug ins from the bathroom forward.  Apparently, everything is connected in series, both ceiling fans, then the under cabinet plug in, then the microwave.  That is one problem.  The other is the leveler control panel, which Thor said powers off the front fuse panel under the dash cover.  I will open that up when I get back home in a couple of days.  They said there is only one power lead going to the control panel.

 

[Gary RV_Wizard]

First terminology problem is whether "a/c" is 'air conditioning' or 'alternating current'.

In any case, it appears you have some 120vac components/subsystems working and others not.  It is crucial to keep in mind that there are both direct and alternating current systems involved and there are multiple power sources for both 120vac and 12dc.  If you don't know which items have a 12vdc dependency and which are 120vac only, you will get terribly confused trying to diagnose.

 

[JoelP]

Is it possible that you are only getting one phase of power from the shore line?  That would power some 120 and not others and would prevent operation of any 240V items like air conditioning.  If the Genset operates these items and the shore power does not it may be possible that one phase is not getting through from shore power.

 

[Alfa38User]

Except.... the RV air conditions are normally 120V BUT, on a 50 amp coach, if there is more than one air conditioner, one would operate from a C/B on one side of the panel and the other from a C/B on the other side of the panel, in order to spread the load over the two "phases" supplied. But the operation or non-operation would be exactly as you said: some stuff would work others wouldn't!! Basement air is similar except that they are divided as compressors 1 and 2 on either side. They are simply two air conditioners in one big box.

(Either left/right sides or upper/lower sides of the breaker panel, depending on its orientation.)

 

[JoelP]

I ran into having half of my outlets working and no 240 when I inadvertently stepped on the shore line one day as I was hurrying to set up in the rain.  It took me a little bit to figure out that I was only getting one phase.  For me it was a matter of pushing the plug in the rest of the way, but for the OP it seems that it is more than that.