Community Forums

Rhobson · 06-22-2021, 10:35 AM

I recently bought a 2008 Allegro Bus 43 QRP and where I bought it said that it had 3 AC units but that on shore power I could only run 2 at a time but if using the generator I could run all 3. Is this right? It doesn't make sense to me but I am new to motor coaching. Here in AZ it is 🔥 HOT 🔥 and it doesn't keep up with the heat when I run 2. I am plugged in to a good 50 amp 220v receptacle and want to run all 3 units. Can this be done safely? Or was the guy at the stealership correct?

wolfe10 · 06-22-2021, 10:42 AM

Quote:

Originally Posted by Rhobson

I recently bought a 2008 Allegro Bus 43 QRP and where I bought it said that it had 3 AC units but that on shore power I could only run 2 at a time but if using the generator I could run all 3. Is this right? It doesn't make sense to me but I am new to motor coaching. Here in AZ it is �� HOT �� and it doesn't keep up with the heat when I run 2. I am plugged in to a good 50 amp 220v receptacle and want to run all 3 units. Can this be done safely? Or was the guy at the stealership correct?

If the three are wired correctly (two to one hot and the other to the other hot along with all other high-amp loads) I see absolutely no reason you can do it on 50 amp shore power.

Said another way, I can't see a way either L1 or L2 load could exceed 50 amps.

96 Wideglide · 06-22-2021, 10:50 AM

What size gen do you have? If less than 12.5KW, it makes less power than a 50A shore connection!

I have 2 15k and 1 13.5k btu heat pumps and frequently run all three on a good shore connection.

Old-Biscuit · 06-22-2021, 11:01 AM

Quote:

Originally Posted by Rhobson

I recently bought a 2008 Allegro Bus 43 QRP and where I bought it said that it had 3 AC units but that on shore power I could only run 2 at a time but if using the generator I could run all 3. Is this right? It doesn't make sense to me but I am new to motor coaching. Here in AZ it is 🔥 HOT 🔥 and it doesn't keep up with the heat when I run 2. I am plugged in to a good 50 amp 220v receptacle and want to run all 3 units. Can this be done safely? Or was the guy at the stealership correct?

So turn them ON......

**Lt Dan** · 06-22-2021, 12:46 PM

I run three all the time on both shore power and generator. Each one draws about 12 amps so 100amps (two legs of 50) is more than adequate. He may have been referring to 30amp service where you would only be able to run two but not much of anything else.

garykk · 06-22-2021, 01:16 PM

First thing is to be sure you have a 50 amp service and not a 30 amp. Some older units did require the genset to be running to operate the ACS. Make sure all the AC breakers are set, throw them and reset. Make sure you are getting 50 amps out of the pedestal, 50 amps on each leg. If that’s good, check the power at the breaker box for power on each leg. If not then it’s the transfer switch.

Old-Biscuit · 06-22-2021, 03:05 PM

Quote:

Originally Posted by garykk

First thing is to be sure you have a 50 amp service and not a 30 amp. Some older units did require the genset to be running to operate the ACS. Make sure all the AC breakers are set, throw them and reset. Make sure you are getting 50 amps out of the pedestal, 50 amps on each leg. If that’s good, check the power at the breaker box for power on each leg. If not then it’s the transfer switch.

OP was 'told' ...no actual issue

wolfe10 · 06-22-2021, 03:12 PM

Quote:

Originally Posted by Old-Biscuit

OP was 'told' ...no actual issue

Told by someone who does NOT know electricity or "read on the internet"-- kind of peas in a pod.

Agree, he needs to determine the FACTS by DOING IT.

And, if a problem, let us know under WHAT CONDITIONS.

Rhobson · 06-22-2021, 10:23 PM

Thank you for the responses. It didn't make sense to me since the generator is only 10kw. I will try it and see if I can cool off a bit.

SargeW · 06-22-2021, 10:48 PM

My Bus has a 10KW gen, and it will run all 3 AC's at one time. My gen puts out 45 amps on each line, but a true 50 amp shore power should do 50 amp on each line. I was just a campground in So Cal on a 110 degree day. Although the pedestal was 50 amp, the voltage was a bit low mid day, in the 106 volt range. So for the 3rd middle AC I switched the fan to Low speed, which dropped the amp draw. All 3 AC's ran without a hitch.