A/C Size for a B

[Toyman]

I have a new Travato, with a 13.5K A/C unit.This A/C makes so much noise that it makes the van unlivable, unless you can turn it on after you go to sleep - neat trick huh. When I bought this I questioned the 13.5K size, my 2 other B's were Sprinter based, one had a 9K, the other had a 11K. I want to change the A/C for 2 reasons, the NOISE, and I don’t feel that the compressor runs enough for dehumidification. What size is in your van, are you satisfied with the NOISE level, cooling & dehumidification ? I’m looking at the Penguin II as a replacement 11K BTU.

[avanti]

Originally Posted by Toyman

I have a new Travato, with a 13.5K A/C unit.This A/C makes so much noise that it makes the van unlivable, unless you can turn it on after you go to sleep - neat trick huh. When I bought this I questioned the 13.5K size, my 2 other B's were Sprinter based, one had a 9K, the other had a 11K. I want to change the A/C for 2 reasons, the NOISE, and I don’t feel that the compressor runs enough for dehumidification. What size is in your van, are you satisfied with the NOISE level, cooling & dehumidification ? I’m looking at the Penguin II as a replacement 11K BTU.

Your complaint is a common one. Most RV roof air conditioners are practically unusable due to the noise. My understanding is that this is largely due to crude air-path and fan designs. Sadly, I don't think you will find an 11K unit much better. Ducted A/C setups are better, but are difficult to accomplish in a B-van.

You really have only a couple of alternatives:
1) Install a split system, with much of the mechanism outside the van. Some people have done this successfully, but others report that it is problematic, especially with under-vehicle installs.
2) Advanced RV imports a high-end rooftop replacement unit that by all accounts is much quieter than a typical RV A/C. They will install it in their Ohio factory, or ship one to you for a self-install. Pricy, though.

[Bud]

avanti, the newer Coachmen 12 volt ac system is suppose to be quiet, FIT RV?

https://www.youtube.com/watch?v=4T3vTdoKBiA

And this:

"This was pretty interesting. Coachmen is now installing 12-volt air conditioning units in their Class B motorhomes. The unit they are using is by ProAir, and it’s a roof mount unit, not an undermount. It’s got a claimed 20,000 BTU rating, which is considerably bigger than your typical RV air conditioner. Those of you who were at the Tampa RV show recently got the chance to hear one of these running in the Coachmen display, and it was pretty quiet.

But the big deal about the 12 volt air conditioning is that it will allow you to run the AC without needing a generator or inverter. For those of you who choose coaches without lithium battery systems, you would even be able to run this air conditioner while driving – again, without a generator. The thickness of wiring to the unit was not too bad (I asked), at only 2ga. In an informal test, I saw the unit pulling amps in the 50-60 range, which isn’t too bad at 12 volts (but granted, this wasn’t in summer). I suppose we’ll have to wait to see what people say about the performance, but I like that they’re trying new things like this at Coachmen."

Bud

[booster]

50-60 amps of 12v power for a 20K btu AC, so too good to be true. That is not even 750 watts. If that is real, it is very impressive.

[markopolo]

http://www.classbforum.com/forums/f5...html#post88095

[booster]

The forum link talks about variable speed DC compressor which are really DC converted to variable frequency drive like the Danfoss cooled frigs. Certainly makes sense.

Does anyone know what they are controlling the speed off of? I suppose it could be as simple as outside temp or maybe inside/outside differential or maybe based on evaporator temp to optimize cooling and dehumidification. It would be slick if it looked at the amount the indoor temp was off of thermostat setpoint and adjusted the speed to get the best recovery/efficiency balance to get to setpoint.

[markopolo]

Originally Posted by booster

50-60 amps of 12v power for a 20K btu AC, so too good to be true. That is not even 750 watts. If that is real, it is very impressive.

From the datasheet sheet photo I posted above you have to anticipate closer to 90 to 100 amps which is very similar to what I see with the 13.5K btu A/C on my motorhome running off the inverter. I think Avanti has sees about the same with with his setup.

I don't know if the 20K btu vs 13.5K btu matters of not in typical usage. It likely would help when in really hot/humid places.

As for quiet, as Avanti noted, a ducted installation makes a real difference. I would have though Advanced RV would have pursued this by now, maybe they have. A ducted installation seems to help performance also. I've had no trouble keeping the 34' motorhome comfortable throughout with the single rooftop A/C. A lot of rigs this size have two A/C's but I suspect part of that reason is that it costs less to install two rooftop units rather than a well designed ducted installation.

[booster]

Originally Posted by markopolo

From the datasheet sheet photo I posted above you have to anticipate closer to 90 to 100 amps which is very similar to what I see with the 13.5K btu A/C on my motorhome running off the inverter. I think Avanti has sees about the same with with his setup.

I don't know if the 20K btu vs 13.5K btu matters of not in typical usage. It likely would help when in really hot/humid places.

As for quiet, as Avanti noted, a ducted installation makes a real difference. I would have though Advanced RV would have pursued this by now, maybe they have. A ducted installation seems to help performance also. I've had no trouble keeping the 34' motorhome comfortable throughout with the single rooftop A/C. A lot of rigs this size have two A/C's but I suspect part of that reason is that it costs less to install two rooftop units rather than a well designed ducted installation.

We see similar amps from our 12K btu Coolcat non rooftop unit, although it would be nice to see in the spec sheet what they actually used for voltage (actual input voltage) for the testing. The current on the Coolcat goes up quite a bit as the voltage drops from full batteries to 50% full. If those amps they list are at actual 12.0v in, they might be considered better by some amount.

[avanti]

Originally Posted by markopolo

As for quiet, as Avanti noted, a ducted installation makes a real difference. I would have though Advanced RV would have pursued this by now, maybe they have.

ARV has built at least one ducted system as part of their "super-tall" project (i.e., a Sprinter with the extra-high factory fiberglass cap). Looked really nice. I don't know if they every replicated the design. As I said, it is difficult to pull off in a B without the super-high roof.

[rowiebowie]

Originally Posted by Toyman

I have a new Travato, with a 13.5K A/C unit.This A/C makes so much noise that it makes the van unlivable, unless you can turn it on after you go to sleep - neat trick huh. When I bought this I questioned the 13.5K size, my 2 other B's were Sprinter based, one had a 9K, the other had a 11K. I want to change the A/C for 2 reasons, the NOISE, and I don’t feel that the compressor runs enough for dehumidification. What size is in your van, are you satisfied with the NOISE level, cooling & dehumidification ? I’m looking at the Penguin II as a replacement 11K BTU.

Does your current a/c have a true low or medium fan speed? I ask because my 6yr. old Coleman had two blower speeds, high and higher, which made it loud, regardess.

My new Coleman Mach 8 Plus (low profile) has a true medium speed along with high. While I'd say on high it is about the same noise level as the old one, it is significantly quieter on medium than the old unit (subjective, no decibel readings). So fan speed can make a huge difference.

Good luck.
.

[avanti]

Originally Posted by rowiebowie

Does your current a/c have a true low or medium fan speed? I ask because my 6yr. old Coleman had two blower speeds, high and higher, which made it loud, regardess.

My new Coleman Mach 8 Plus (low profile) has a true medium speed along with high. While I'd say on high it is about the same noise level as the old one, it is significantly quieter on medium than the old unit (subjective, no decibel readings). So fan speed can make a huge difference.

Good point. I have had good luck modifying a too-fast blower motor in our Rixen's Espar hydronic liquid to air heat exchanger using a cheap PCM fan controller from eBay. I have been thinking of trying the same thing in our Dometic A/C. I don't know if this would lead to ice formation, though.

[jon]

Originally Posted by rowiebowie

Does your current a/c have a true low or medium fan speed? I ask because my 6yr. old Coleman had two blower speeds, high and higher, which made it loud, regardess.

My new Coleman Mach 8 Plus (low profile) has a true medium speed along with high. While I'd say on high it is about the same noise level as the old one, it is significantly quieter on medium than the old unit (subjective, no decibel readings). So fan speed can make a huge difference.

Good luck.
.

I too have a new Coleman Mach low profile. Mine is the 9200 BTU one and i was reading on low cool it reduced the outside unit fan as well as the inside fan. It is far less noisy than i thought it would be. I previously had a 12 volt system that didn't work that well.
I wanted a rooftop unit for the superior air flow and i think 9200 BTU would help dehumidifie the van.

[JohnnyFry]

A couple of developments have me curious about improving the AC systems in class Bs. First, several vehicles, Suburbans for example, offer a second evaporator/fancoil unit in the back to cover the back seat passengers. Secondly, all the electric vehicles (Tesla, Leaf, BMW i3) have electrically based AC systems which, presumably, use 3 phase inverter driven compressors) Why can't that second fan coil unit be used in a class B along with a DC inverter driven compressor mounted under the hood and a fan cooled condenser in the normal location in front of the radiator. Having both the dash mounted and rear ceiling mounted AC units would give much more even cooling...something sorely lacking in my RT 210P where the rear ices down and the front is broiling. These automotive (dash and ceiling) units running on low fan would be much quieter than what we have now and, I am told, quieter than the split underfloor units offered now. A variable speed compressor (a reality with inverter driven compressors) could reduce power consumption and lower noise levels further.

[booster]

Originally Posted by JohnnyFry

A couple of developments have me curious about improving the AC systems in class Bs. First, several vehicles, Suburbans for example, offer a second evaporator/fancoil unit in the back to cover the back seat passengers. Secondly, all the electric vehicles (Tesla, Leaf, BMW i3) have electrically based AC systems which, presumably, use 3 phase inverter driven compressors) Why can't that second fan coil unit be used in a class B along with a DC inverter driven compressor mounted under the hood and a fan cooled condenser in the normal location in front of the radiator. Having both the dash mounted and rear ceiling mounted AC units would give much more even cooling...something sorely lacking in my RT 210P where the rear ices down and the front is broiling. These automotive (dash and ceiling) units running on low fan would be much quieter than what we have now and, I am told, quieter than the split underfloor units offered now. A variable speed compressor (a reality with inverter driven compressors) could reduce power consumption and lower noise levels further.

Similar ideas have been discussed here recently on another thread. Basically it was about having an electric drive to turn the existing vehicle compressor to run the dash AC. IIRC there are worries about also needing to run the radiator fan if electric or adding one if not and also the dash fan. You should be able to find that discussion with a search, it was not very long ago.

[Bud]

Just returned from sitting, listening.... PleasureWay Lexor, Travato and Beyond (Crossfit).

The Lexor onan was the best I've heard inside and out, BUT the a/c is too Loud. Did not listen to the Travato. The Beyond a/c was very quiet with the fan speed infinitely variable, I suppose that will work with an app on your phone too. Again, very quiet, compressor running on the agm batteries! I also listened to onan, seemed louder than the Lexor onan. The Proair is expensive, worth every penny depending on your pocketbook. If buying new and the person is going to really use the a/c, the Proair or ARV is a no brainer, imo

Does Coachmen have an advantage here with the 12 volt a/c (no inverter). Me, always thought of lithium as in a/c. Now 1 or 2 agm's could be added for a reasonable? amount of time and used with alternator and shore power as Mike described some, or just the 2 std agm's. That ac is quiet.

The seats: I did not like the seat or seating position of the Promaster's (Lexor or Travato) compared to the Beyond Ford Transit or Sprinter or Express Van.

I might talk with Coachmen next week about proair on batteries only. Then I'm heading to a mental health care professional to ask why the heck I'm doing this? Habitat for Humanity could/can spend the $'s more productively, and I keep the present B.

[Bud]

Originally Posted by Bud

Just returned from sitting, listening.... PleasureWay Lexor, Travato and Beyond (Crossfit).

The Lexor onan was the best I've heard inside and out, BUT the a/c is too Loud. Did not listen to the Travato. The Beyond a/c was very quiet with the fan speed infinitely variable, I suppose that will work with an app on your phone too. Again, very quiet, compressor running on the agm batteries! I also listened to onan, seemed louder than the Lexor onan. The Proair is expensive, worth every penny depending on your pocketbook. If buying new and the person is going to really use the a/c, the Proair or ARV is a no brainer, imo

Does Coachmen have an advantage here with the 12 volt a/c (no inverter). Me, always thought of lithium as in a/c. Now 1 or 2 agm's could be added for a reasonable? amount of time and used with alternator and shore power as Mike described some, or just the 2 std agm's. That ac is quiet.

The seats: I did not like the seat or seating position of the Promaster's (Lexor or Travato) compared to the Beyond Ford Transit or Sprinter or Express Van.

I might talk with Coachmen next week about proair on batteries only. Then I'm heading to a mental health care professional to ask why the heck I'm doing this? Habitat for Humanity could/can spend the $'s more productively, and I keep the present B.

It may not have been clear above. There was no Li3 system with the Beyond.

[Boxster1971]

Originally Posted by markopolo

... As for quiet, as Avanti noted, a ducted installation makes a real difference. I would have though Advanced RV would have pursued this by now, maybe they have. A ducted installation seems to help performance also. I've had no trouble keeping the 34' motorhome comfortable throughout with the single rooftop A/C. A lot of rigs this size have two A/C's but I suspect part of that reason is that it costs less to install two rooftop units rather than a well designed ducted installation.

As avanti mentioned - Advanced RV did make a ducted A/C installation on the super-high roof Sprinters. They had enough ceiling height for the ducting.

https://advanced-rv.com/escape/

[rowiebowie]

Originally Posted by Bud

Just returned from sitting, listening.... PleasureWay Lexor, Travato and Beyond (Crossfit).

I might talk with Coachmen next week about proair on batteries only. Then I'm heading to a mental health care professional to ask why the heck I'm doing this? Habitat for Humanity could/can spend the $'s more productively, and I keep the present B.

Think of all the good people at Coachmen you'll be employing while they build your new Beyond. Somebody besides me has to keep the economy humming.

Thanks for your quick review of those models.
.

[Roadtech]

Originally Posted by Boxster1971

As avanti mentioned - Advanced RV did make a ducted A/C installation on the super-high roof Sprinters. They had enough ceiling height for the ducting.

Coach House has ducted air conditioning in their Arriva Class B in a standard height (9' 8" incl. A/C) Sprinter with 6' 2" interior headroom. So it can be done.

[Boxster1971]

If this new compact window A/C ever becomes available it could be used as a portable unit installed in one of the cab windows when parked.

https://www.kapsulair.com/pre-order