Roof vs Cruise air

[flloyd]

I've looked into adding a couple of electric radiator fans to the front of my Liberty. 2 of the CA units are behind the front bumper. The grille behind the bumper lets fresh air into the compartment, except when the air operated shutters are closed. Normally, the shutters are open whenever the coach is parked. This seems like a perfect place to mount a couple of radiator fans and a baffle to pressurize the entire compartment and hence the two CA units inside which both exhaust downward.

There is some debate about the purpose of the front shutters and some folks (e.g. Doug at Excalibur) told me that he routinely rips them out altogether. Liberty told me that they were designed to be closed while the coach was in motion to prevent debris from getting into the compartment, and to relieve a situation whereby hot or cold ram air could come into the passenger compartment around the driver's area.

Still, it looks like it would be pretty easy to mount a pair of 12" radiator fans with a cut-out baffle on the inside, behind the shutter assembly. I measured the area and it's a good fit for a pair of them.

I didn't get to start this project but one thing I did notice was that the sealing boot around the steering rod is torn as the rod exits the compartment. It doesn't look easy to replace and so I might suffer some loss of compartment pressurization there.

Overall it looks like a fairly easy project that I may still try next winter when the weather in Arizona is more suited to performing repairs and mods.

Meanwhile, my number 1 problem with running my 4 CA's is the power consumption. With all four of them turned on, it is a near certainty that the 50A breakers in the park pedestal will trip. My inside ammeters are usually reading about 35-40 Amps each in this mode and so we've learned that 2 CA's are safe, 3 are a maybe, and 4 are impossible unless we're running off the generator.

A good workaround has been to install a small portable fan outside that aims into the breaker box, allowing us to be fairly safe on 3 units in hot weather. It's frustrating.

[Jon Wehrenberg]

Fred,

Power management as you know is required to run all 4 CAs. When I want to beat the heat I use all 4 but turn off the HW tank and make sure I don't use any high amp loads like a coffee maker or the microwave. When all 4 are running and I have some lights on and the TV my current draw is around 32 to 33 amps. I have my inverters set at the lowest charge rate so they are not a factor even if I turn on all the lights. In the morning when it is cool I can make coffee, use the dryer or turn on the HW tank because I only have to run two CAs.

Any 50 amp service should easily handle those amperage loads and if the shore power breaker trips it is likely a bad circuit breaker or the connections are loose.

[Kenneth Brewer]

Fred,

Power management as you know is required to run all 4 CAs. When I want to beat the heat I use all 4 but turn off the HW tank and make sure I don't use any high amp loads like a coffee maker or the microwave. When all 4 are running and I have some lights on and the TV my current draw is around 32 to 33 amps. I have my inverters set at the lowest charge rate so they are not a factor even if I turn on all the lights. In the morning when it is cool I can make coffee, use the dryer or turn on the HW tank because I only have to run two CAs.

Any 50 amp service should easily handle those amperage loads and if the shore power breaker trips it is likely a bad circuit breaker or the connections are loose.

My experience is the same: any good park electrical system/pedestal handled all 4 CAs, even here in Texas, NM. AZ, and even Indio or Phoenix, if the HW heater is up to temp prior, and only one inverter charger is set to low amps (>10) and the other turned off. The microwave, rangetop or curling iron would sometimes trip the pole breaker, and an argument would also occasionally arise when one person forgot or ignored previous instructions.

[gmcbuffalo]

Fred why try to pressurize the compartment why not just put the fans blowing into the each CA units compressor coils?

[GDeen]

Fred,
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Why are you not using the OTR on that bus? Screw cruiseairs for cooling while in motion....fire that big boy up! We were in hours of 106° F + on our first day of this trip, and the coach interior was comfortable in the high 60's running the bus air.

[flloyd]

Fred,
-
Why are you not using the OTR on that bus? Screw cruiseairs for cooling while in motion....fire that big boy up! We were in hours of 106° F + on our first day of this trip, and the coach interior was comfortable in the high 60's running the bus air.

Oh yes, I do use OTR whenever possible, or when I need to hang beef. My discussion here is only about park operations.

[flloyd]

Fred why try to pressurize the compartment why not just put the fans blowing into the each CA units compressor coils?

It's an ease of installation issue. I don't really want to pull the compressor units, and there's not much room to work down there.

[flloyd]

My experience is the same: any good park electrical system/pedestal handled all 4 CAs, even here in Texas, NM. AZ, and even Indio or Phoenix, if the HW heater is up to temp prior, and only one inverter charger is set to low amps (>10) and the other turned off. The microwave, rangetop or curling iron would sometimes trip the pole breaker, and an argument would also occasionally arise when one person forgot or ignored previous instructions.

Speaking of which, I swear that my wife's hair dryer draws more current than a single CA! It's about 1500W

[Jon Wehrenberg]

That's where power managment comes into play. She has the power to decide when she will use her hair dryer and you have to manage the circuit breakers so the shore power doesn't trip.

[Jerry Winchester]

If I over amp at a park, 90% of the time it can be traced to a hair dryer or flat iron. A hair dryer must be akin to a dead short.