fuse flipping

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RVRAC

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Jun 11, 2012
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The breaker for my AC/Heat pumps is flipping.  When I turn on either one, it works for 5-10 minutes but then flips.. It is a 20 amp.  What can be wrong?
 
Yeah, my 1st guess would be low voltage too. Do you have a power monitor that display's A/C voltage? If you're plugged in at a campground, can you disconnect from shore-power and try running your AC off your generator to see if the breaker holds?

Kev
 
Yeah, I am connected to the campground power.  Sorry but don't know how to check the voltage.  Help please!
 
If you don't have an in-line surge guard/power monitor that displays incoming voltage, or if your coach's energy management system doesn't display A/C voltage, you can use a VOM and (carefully) stick the probes into one of your A/C sockets. I'd recommend measuring the voltage while the A/C (heat pump) is off and then again, while it's running.

Kev
 
RVRAC said:
Yeah, I am connected to the campground power.  Sorry but don't know how to check the voltage.  Help please!

You can either get a surge protector something like Progressive Industries put out, which I highly recommend, or you can get a cheap digital voltmeter to check it. The surge protector monitors and has a display window telling you what the incoming voltage is.. And it will protect all your electronic devices in the RV if you ever have a power surge.
 
Rene, I got a Progressive surge protector.  What should I look at exactly? 
These are the readings I am getting:
Off: L-1, 121, 0A; L-2, 119 4A
ON: L-1, 122, OA, L-2 119, 17A

EO, 60H

I am not sure what to do with these readings.
 
RVRAC said:
Rene, I got a Progressive surge protector.  What should I look at exactly? 
These are the readings I am getting:
Off: L-1, 121, 0A; L-2, 119 4A
ON: L-1, 122, OA, L-2 119, 17A

EO, 60H

I am not sure what to do with these readings.

What do you mean by ON and OFF?
 
At one time or another that has happened on all my Air COnditinoers (Do not have heat pumps) In every case I went up and cleaned the evaporators and all was good.. I started with two Carrier Air V's (Which of course I'll never have avain less I buy a USED RV.. (They no longer make 'em)) replaced one with an ADVDENT air which like the carrier and most all others save Coleman blows,,, Meaning the condenser fan sucks air in from the sides and blows it through the condenser so you have to take it all apart to clean it.

The fan on teh Advent (A product of China) Turned out to be like China Tires.. A BOMB (Blew up) and it was replaced with a Coleman fan, the othe Carrier was replaced with a Coleman so not they SUCK, meaning they pull air in via the condenser and are a WHOLE LOT EASIER TO CLEAN.

But that's what I had to do to make the breakers happy. Clean the beasts.
 
Rene,

I meant off when the AC/Heat pump is off. Likewise On meant when the AC/Heat pump is on.  I am getting different readings depending on whether the unit is on or off.  I don't know if this is correct or not.
 
RVRAC said:
Rene,

I meant off when the AC/Heat pump is off. Likewise On meant when the AC/Heat pump is on.  I am getting different readings depending on whether the unit is on or off.  I don't know if this is correct or not.

OK.
Looking at the readings, you don 't have a power issue. L1 is for one leg of the cord powering your RV and L2 is the other leg powering the RV. You're running between 119 and 122 volts which is great.
The A with the number before it is telling you how many amps you are drawing on that particular leg at that time. You can see that when the heat pumps are on, you are drawing more amps on the L2 leg. 
The EO means everything is fine.

I'm not a electrician but seeing you are drawing 17 Amps on a Circuit with a 20 Amp breaker, maybe the breaker is a little weak.  Others will chime in with much more experience then I have when it comes to electricity.
 
RVRAC said:
Rene, I got a Progressive surge protector.  What should I look at exactly? 
These are the readings I am getting:
Off: L-1, 121, 0A; L-2, 119 4A
ON: L-1, 122, OA, L-2 119, 17A

EO, 60H

I am not sure what to do with these readings.

To add to what Rene said:
  L-1, 121, 0A is Leg 1, 121 volts, 0 amps
  L-2, 119, 4A is Leg 2, 119 volts, 4 amps
similar in "ON"
  E0 is no errors, 60H is 60 Hertz frequency (perfect).
 
What the readings say is leg 2 is pulling 4 amps without the AC running. With it on, it?s pulling 17 amps on leg 2, which means the AC is pulling around 13 amps, well under the 20 amp rating of the breaker that?s tripping. I?m thinking the breaker is bad, or the connection is loose at the breaker which generates heat and can cause the breaker to trip below it?s rating. First thing I would try is turn off that breaker, try tightening the connection at the breaker, then try the AC again. Often you can just feel the breaker and see if it?s hot to the touch, which can be caused by a loose connection.
 
Could still be voltage drop issue.
Your readings show very little or no voltage drop now but you really don?t have a load on the system.
Add the 13A for A/C and you could be much higher
Voltage drop is really only evident when load added.
Check your readings when A/C running and post info.
 
There are many components which run of 110 Volt AC, Electric heater in fireplace, ceiling fan, microwave, water heater, refrigerator (residential or RV), Hair blow dryer, curling iron, toaster, crock pots and toaster ovens. If some of these items are wired to that same circuit and you're running some of those while your running your heat pumps, it will put you over the top of top of the 20 Amp circuit and it will trip. A manufacturer shouldn't wire anything like that but you never know.
On L2, with the heat pumps off, you re still drawing 4 Amps. Could they be wire on the same circuit?  Just wondering.
 
Your readings show very little or no voltage drop now but you really don?t have a load on the system.
Add the 13A for A/C and you could be much higher

Those numbers show no change in voltage (119v) when the 13A load of the a/c is ON, so I doubt if voltage drop is a problem here.

I think Rene has it: Either (1) there is some additional device sharing that breaker and it cycles on (a thermostat?) and causes the trip, or (2) the breaker is a little weak and trips under a continuous 13A load. The rated sustained load for a 20A breaker would be 16A, so 13A is close enough that a weak breaker could do it.

There is a 3rd possibility and that is varying voltage in the campground power. The values listed here are fine, but it's is possible the campground suffers momentary voltage dips that are enough to cause the problem. I rate that as "not very likely" given that the numbers shown here are excellent, but it's a possibility.
 
He said it takes a few minutes.  Just like mine did when in need of cleaning. Here is what happens.

IF the Condenser coil does not have good air flow then it can not shed heat as fast as it should.
As the system heats up the pressures increase. as the pressures inrease the compressor works harder and harder, the harder it works the more amps it draws.. Mine was up to 21 amps when the breaker broke (tripped)  As I said I cleaned it, and suddenly the system was drawing rated amprage again, even after 30 minutes or more of operation (after that I stowed the clamp on meter and closed up the box)

I still vote for a coil  clean.
 
Rene, the L-2 looks like the only leg pulling some amps, as the L-1 is 0 all the time.  Thus, when the AC/Heat pump is on the total drawing of all systems is around 17, and 2-4 when the AC/Heat pump is off.  When the AC/Heat breaker flips nothing else loses power, so I think it is a dedicated braker. Does this make sense?
 
This is a brand new RV so I think cleaning the condensor wouldn't fix it but it's worth a shot. Maybe you got into an area where there was a lot of dust/dirt blowing around. Who knows. If you do try to clean it, be careful with the pressure from the hose. It will bend the aluminum fins.
It also wouldn't take much to change out that breaker.
 

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