Replacing the main 30/20 split breaker in our 2014 27FB

[Rocinante]

Hey, everybody. It's that time: the breaker is still working, but it's gotten warm and popped enough times that I think we should replace it.

I would appreciate any thoughts you may have on the best place to find this odd breaker. It has so far been impossible to locate one. (When I do find one, I'm buying two of them!)

Per the photo, it is the breaker on the left, a Siemens, Type QT, Class CTL, No Common Trip circuit breaker, with Two 1 Pole Units, Issue No. N-20.

Nobody seems to have heard of this beast before.

Here's a photo:

[rmkrum]

From the looks of the panel, you should be able to find a Square D equivalent 30/20 breaker to fit that panel...does not have to be a Siemens...

[uncle_bob]

Hi

Based on this product sheet:

https://www.homedepot.com/catalog/pd...57df839ba0.pdf

It looks like you want a Q2030.

Assuming that looks correct compared to what you have, I'd talk to the big box special order desk and see how that goes. If it gets you nowhere, the local full blown electric supply outfit is the next stop. Standard order quantity appears to be 12 pieces ... sorry about that.

It's not uncommon for these half sized guys to get a bit warm. They also are not quite as rugged as the bigger units. It's worth swapping out. I'd also check the circuit with a clamp amp meter to see how close to limit you are getting.

Bob

[AirstreamJim]

I found the Square D version at a local full-service electrical supply house. Home Depot and Lowes would have ordered it but I wanted it "now." Just bring the old one and they will match it with what they have.

Jim

[DreamStreamr]

One of our local RV parts place carries these, $17 (http://parts.billplemmonsrv.com/20-3...rcuit-breaker/)

I picked up one of the split breakers years ago, still carry it in my "stuff" box. Bought it at the Airstream factory store in Jackson Center. Haven't needed to replace any breakers so far (4,000+ nights in this Airstream).

Have you figured out why you're tripping the breaker? Friends in our local Unit also trip theirs. They have an electric coffee pot and an electric water heater. We sometimes use the microwave at the same time as the roof air/heat and fridge so it would seem like we'd overload the 30 amp breaker enough to trip, but nope. I guess we've just lucked out so far.

These are my actual readings:
Roof air 15 amps (resistance coil, not a heat pump)
Microwave 16 amps
Fridge 3 amps
Intellipower 2-8 amps

[AtomicNo13]

It's a common square D split breaker. Common at Ace, true value, and other box stores.

[Rocinante]

Thanks for the replies!

AtomicNo13: The 30/20 split breaker is *not* a Square D split breaker. The other split breakers with 20/20 are indeed Square D, but this one is not.

Looks like Uncle Bob hit the nail on the head, I do indeed appear to have a Siemens Q2030 breaker.

Per a couple of suggestions above, I will look for an equivalent Square D in case I can find one.

My current theory on why the breaker gets warm and pops is that Airstream did a silly thing, putting the heat pump on the 20 of this split breaker. That means the heaviest possible long-time draw comes in and out of the two switches on this one split breaker.

As a result, I am also considering swapping the microwave oven circuit with the AC circuit to reduce the potential for heat buildup caused by those two simultaneous heavy draws on the same pair of breakers over an extended period of time. The microwave isn’t used as often, nor is it used as long as the heat pump, so that might help too.

If we use the heat pump, we make sure the water heater is off, and we don’t operate the microwave. One possibility, however, is that the Progressive Dynamics 4650 will periodically put itself into bulk mode, which generates a heavy draw. One other thought is that on warm days, the Dometic fridge draws more current than usual in an effort to keep the contents cold.

I have noted on our surge protector that it indicates we are drawing 19 amps when the heat pump is running. That suggests some of the other items I have mentioned above (aside from the water heater) must also be operating while the heat pump is on. Even so, 19 amps should not be enough current to pop a 30 amp breaker. (Sigh)

I have a clamp meter, and if I can figure out how to get it back there while current is running (without zapping myself!), I would love to measure some amperages.

[AtomicNo13]

My 91 has all square d breakers.
One is a gfi breaker, one a split and the other 2 single gang breakers.
Given the somewhat weaker nature if these split breaker, I find it odd they use one as the master breaker.

[Rocinante]

Originally Posted by AtomicNo13

...
Given the somewhat weaker nature if these split breaker, I find it odd they use one as the master breaker.

I agree with your observation 150%. It makes no sense at all to me that they did this. In fact, I might argue that it's something of a safety issue.

They should have had a single 30 amp breaker into the trailer, and then they could have split the rest. Must have saved a couple of bucks by doing it this way.

Meanwhile, we're in Myrtle Beach, SC, right now, and given the huge volume of RV traffic here in summer, I'm going to check out a few local RV dealers for parts as well as any home improvement stores and hardware stores. Maybe I'll get lucky.

Oh, this cool 55 degree morning I watched our surge protector while starting the heat pump in both heat and cool settings. Turned off all other breakers to be sure there would be no confusion. In both modes the heat pump draws around 14-15 amps to start and then 12-13 to run. So, there's nothing wrong with our heat pump. The larger 19 amp draw I mentioned above was on a hot afternoon, though I'm not sure what else was drawing at the time. At that moment it didn't occur to me to shut off all other breakers to see what would happen to the draw.

(The low amperage to start is probably due to the EasyStart gadget we installed earlier this year, and the fact that the display on the surge protector probably doesn't update fast enough to truly capture peak draw when starting the heat pump.)

[DreamStreamr]

When I replied to you last night my EMS was reading 33amps. If my PDI Intellipower had kicked into bulk mode then yep, the extra 5-7amps would have probably tripped the 30a breaker. So being lucky is okay for now.

The only 120v circuit realignment I did was to move microwave (pretty sure it was) off the PDI breaker so I could switch the PDI easily. Granted, we're not supposed to use breakers as switch devices. But we're not switching a loaded circuit, doing it once a week or so. And it allows the solar charging to stay in control of the batteries for most all the summer.

[Rocinante]

Thanks, Jim.

Looks like I may have found a parts supplier here in Myrtle Beach who has these breakers in stock. If they do, I will buy a couple just to have one "in case" for the future.

Then I'll try out my wiring theory above, as I don't like the possibility of continuously pulling a combination of up to 25+ amps on the 30-amp split as well as 13-20 on the 20-amp split, all in the same little split-breaker case. It just seems silly to wire it that way when I could put the microwave there instead. I know a microwave can pull some big amperage as well, but it's for just a few minutes at a time because we don't try to cook anything big in there. That should help reduce the heat dispersion issue on the 30 amp breaker and keep that split breaker cooler overall.

I pulled off the cover for the breakers to take a look in there and found that they did not leave room for more than three breakers. By splitting each one, they got six breakers. They could have made room for another just for the 30 amps coming into the trailer because there is enough space, but they mounted a bus bar across the top of the remaining space which prevents mounting anymore breakers unless I find a new home for the bus bar. Maybe someday, but not today. For now, we'll just try a new breaker in that spot and a minor wiring change to see what happens.

[uncle_bob]

Hi

If you happen to be wandering around on the roof of the trailer with nothing much to do .... pop the cover on the AC and check the capacitors. They do wear out. It would be really odd for one to go in 4 years or so. It does happen. As they wear out the max current can climb a bit. They are cheap enough that the replacement cost is not a big deal.

If you don't already have a meter that will check motor capacitors, this is a great excuse to put one on your Christmas list My latest "do it all" gizmo is a Fluke 325. There are a *lot* of alternatives.

Bob

[Rocinante]

Here's an update and (hopefully!) final chapter on this issue.

This afternoon, when I got ready to start the planned work, I found something I had missed before. The 10 gauge white wire that connects to the AC power bus, obviously part of the 30 amp circuit, had clearly become very hot in the past: the insulation was bubbled / charred for an inch from that connection. When I inspected the connection, it seemed less than ideal. The wire actually wiggled a bit!

This poor connection and resultant hot wire must be what was causing the 30 amp breaker to get so warm, as opposed to my previous theories.

To resolve the situation, I cut back the 10 gauge white wire to where it was good, stripped about 1/4", smeared some Ox Guard on the clean wire, shoved it into a wire butt designed for 10 gauge, and crimped it. Then I took another fresh length of white 10 gauge wire, stripped 1/4" of that, smeared Ox Guard on that, shoved it into the other end of the butt, and crimped it. Lastly, I took the end of that new wire, stripped 1/2", smeared it with Ox Guard, put it back into the bus, and screwed it down tight.

Next, as planned, I replaced the now clearly compromised 30/20 breaker that got me started on this whole project. The old breaker looked fine, but all that heat has to have caused some damage, and I had the new breaker, so I swapped it out.

Lastly, I tested everything, running each high-draw appliance while keeping a sharp eye on the new wire and the new breaker. No heat, no issues, everything looks good!

I did not move circuits around as I had previously intended, because the overheated white wire and poor connection to the bus bar were pretty obviously the cause of all the problems I had seen.

So, the lesson in all this? Every now and then, it's clearly worth my while to disconnect my RV from power, open up the power center, and check / tighten up all the screws that hold those wires in place!

[A W Warn]

I do not think it is proper that Simens and Square D breakers are used together in the same control panel box. The breaker should be the same type and brand as the control panel box, so that there is proper contact surface between the conductor and the breaker. Maybe that is why it is overheating and tripping.

[Rocinante]

Originally Posted by A W Warn

I suggest that the breakers and control panel box should be made by the same manufacturer. I do not think it is proper that Simens and Square D breakers are used together in the same control panel. The breaker should be the same type and brand as the control panel, so that there is proper contact surface between the conductor and the breaker. Maybe that is why it is overheating and tripping.

Pretty sure it was the poor contact between the white 10 gauge wire and the bus that I mentioned above. However, if the problem re-surfaces, I will either look for a Square D breaker for the 30/20 switch, or replace the two Square D 20/20 split breakers with Siemens 20/20 split breakers.

[A W Warn]

Originally Posted by Rocinante

Pretty sure it was the poor contact between the white 10 gauge wire and the bus that I mentioned above. However, if the problem re-surfaces, I will either look for a Square D breaker for the 30/20 switch, or replace the two Square D 20/20 split breakers with Siemens 20/20 split breakers.

It is not an either or choice. Breakers should be the same brand as the box, so that they will fit correctly onto the conductors, those metal buss bars that the breaker snaps onto.
There should be a label on the box itself or on the inside the cover that says what brand and type it is.

add edit:
some additional information/WARNINGS on this subject
https://inspectapedia.com/electric/C...er_Warning.php

[Rocinante]

Ah, ok. Then I'll check for a brand on the box. Thanks.

Anybody wanna bet that it's a third unrelated brand?

[Jammer]

Originally Posted by A W Warn

I do not think it is proper that Simens and Square D breakers are used together in the same control panel box. The breaker should be the same type and brand as the control panel box, so that there is proper contact surface between the conductor and the breaker. Maybe that is why it is overheating and tripping.

It is common for 3rd party breakers to have a supplemental label for the panel box authorizing their use. Whether the supplemental label supplied with the breaker was actually placed on the panel box by airstream is another question I guess, but I would be very surprised if there is a compatibility problem.

It is a good idea to tighten the screw connections in the breaker box every once in a while. They come loose with heat cycling and vibration. This should also be done on the DC side.

[AtomicNo13]

Good electrical grease and frequent tightening if breaker logs is very important.
Loose conditions lead to poor contact which equals heat.
Same goes for oxidized connections.

[guskmg]

If you want to reduce the heat, but still use the split 20 breaker, consider the MicroAir SoftStart. It cleans up the AC characteristics and reduces starting load. Also, swapping the microwave and A/C loads sound like a low cost solution. I agree the terminal connections should be dielectrically greased as well as tightened. I have found plenty of heat related electrical problems due to loose terminals. Some have cost big bucks in damage before detection and correction.
guskmg