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Dash Air

Since I am thinking about ac these days...
Wonder what BTU's the dash air puts out when they work properly? Craneman, do you know?
Had issues with it the last trip. If I can't get it working without spending a lot of money, I might just put in a third atwood ductless ac in the front to replace it. Read thru a lot of back posts on this but did not find the btu rating, but someone said it puts out more than the roof top ones. That got me thinking.....
'99 U320 40 WTFE
Build #5462,
1500 Watts Solar 600 amp Victron lithium
2012 Jeep Grand Cherokee Overland Hemi
Instagram bobfnbw
Retired

Re: Dash Air

Reply #1 –
Quote from: Bob and Julie –
Since I am thinking about ac these days...
Wonder what BTU's the dash air puts out when they work properly? Craneman, do you know?
Had issues with it the last trip. If I can't get it working without spending a lot of money, I might just put in a third atwood ductless ac in the front to replace it. Read thru a lot of back posts on this but did not find the btu rating, but someone said it puts out more than the roof top ones. That got me thinking.....
22000 btu's
1999  Foretravel U320  Specifications
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.

Re: Dash Air

Reply #3 –
IMHO many of those BTUs are spent cooling the dash ducts and the front end of the firewall.    A 12000 firewall mounted or minisplit would at least equal the  cool total value .  IMHO  .

Re: Dash Air

Reply #4 –
Quote from: Protech Racing –
IMHO many of those BTUs are spent cooling the dash ducts and the front end of the firewall.    A 12000 firewall mounted or minisplit would at least equal the  cool total value .  IMHO  .
Where would you put the compressor and condenser?
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.

Re: Dash Air

Reply #5 –
Any place that has room .  I dont know what the nose of your bus looks like , but anywhere that you could get some air. 

Re: Dash Air

Reply #6 –
Quote from: Protech Racing –
Any place that has room .  I dont know what the nose of your bus looks like , but anywhere that you could get some air. 
Maybe  easier with a GV, but in the OP's  coach, no room, maybe with a coach that has the radiator attached to the generator, but not on his coach.
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.

Re: Dash Air

Reply #7 –
Might consider one of the floorstanding units that contains both condensor and evaporator, vent it out the small kitchen sliding window.  Nice thing is you can remove and store it seasonally and zero installation hassles or footprint.  They actually work far better than expected.  Often available deeply discounted.  A minisplit installation will be very complex....and limited in BTU capability if 120 Volt.

Amazon.com: floor standing ac unit
"Not so  long ago we were a nation of risk takers, riding five million pounds of  thrust straight into space."  Joe Gresh
Chuck Pearson
1996 U295
2018 Can Am X3 TurboRS

Re: Dash Air

Reply #8 –
Bob, the dash air works great on my coach. I have read all the negative posts about coaches that owners spend money on and still don't have it working. These coaches came from the factory with working air and they can be made to work again. The physics of them is no different than an automobile. I fought mine at first and threw a couple  of expansion valves at it to try to get the pressures to match what automobiles have. Finally just accepted the fact that I only needed the dash registers to be cold. I had already put a new compressor on when I first got the coach home as the old one was toast. After removing the second expansion valve, I flushed the system, put a new receiver dryer on and charged it slowly watching the dash register temp. when it dropped to 40 deg. stopped adding Freon. That is the way it still is now, but if I put gauges on the low pressure reads less than 30 psi. It should be around 60 psi but that makes the high side too high. Logic tells me there is a restriction in my system but at this time I  am happy to just have cold dash air. Some time in the future I will evacuate the system again and look for the restriction and eliminate it.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Dash Air

Reply #9 –
A large majority of Coach air conditioning problems may well boil down to you a poorly sealing or open outside air damper for the defrost function. This will be more evident in areas with high humidity. I may well lock mine closed. Coach probably leaks more than enough air for 95% of the time because i don't do much traveling in cold climates. First clue to look for is excessive condensate from the coach. This also applies to the roof a/c units, if you have a steady stream of condensate you are using a boatload of energy unless you are showering or cooking. Vents or windows should be closed, and  most air leaks sealed. Use exhaust fans to take 
Care of this then than shut them off..
Old Phart Phred, EIEIO
89 GV ored 36' #3405 300 hp cat 3208 ATAAC side radiator, mountain tamer exhaust brake

Re: Dash Air

Reply #10 –
Phred, I live in Corpus Christi Texas. Very high humidity here. Doesn't matter what I do, the moisture is there. But you're right about air infiltration. Need to get that better. PO took out the propane fridge but didn't seal up the vents well. Plus the exhaust fan in the kitchen let's in air too. ...
'99 U320 40 WTFE
Build #5462,
1500 Watts Solar 600 amp Victron lithium
2012 Jeep Grand Cherokee Overland Hemi
Instagram bobfnbw
Retired

Re: Dash Air

Reply #11 –
I just went through this with my 97.  We picked up the coach ten days ago.  I ended up replacing the compressor, condenser, condenser fan, receiver/dryer, two sensors, and some lines that were twisted.  They messed up the wiring on the sensors, so I still have to work through that.  On a 30 mile drive last weekend in central Texas, I still needed to run the roof units, but it was nice to have a little cooling coming off the dash.  My brochure rating of 17,250 btus seems optimistic.  Maybe it'll be easier to tell on a longer trip.  I should be able to get by without running the generator nine months of the year and just start it up the last 30 minutes before arrival to get things cooled off for when we get there.

Unfortunately, humidity is a fact of life for central and south Texas.  The moisture gets into everything (cabinets, carpet, clothes, etc.) in between trips and it takes about 24 hours to get it from 90 degrees 80% humidity down to 75 and 50%.  The rear air ran from 3PM until 3AM without stopping.  The dash air just can't fight all that on it's own.  The trip home was much better than the trip there because the 40' column of air behind the driver was much drier after a weekend of air conditioning.

The jury's still out on having the resonator located closer than I'd like to the condenser.  Hopefully, with a resonator, it's evacuating the heat faster than the old muffler did.  The exhaust has to go somewhere and I'd rather it be on the a/c condenser side than the radiator side.

I'm not at the point where I would recommend fixing up the dash air yet, but give me a year and I'll get back to you.
Rick and Donna
1997 U320 4000 WTBI Build 5152 "Molesley"

Re: Dash Air

Reply #12 –
As long as your condenser fan is running your exhaust heat won't bother the condensing temp because you are pulling outside air, however I highly recommend you insulate your receiver/drier and the engine compartment liquid line heading to the evaporator. There isn't much airflow over the receiver so you will lose some BTU's from the exhaust heat that is really needeed at the dash.  Other note is that humidity doesn't affect the condenser but does cause major issues with the evaporator (water/icing).
I've done a lot of work in Corpus Christi for a grocery store and I'm very in the aware of the high humidity with designing their refrigeration systems. I remember last August I drove to Corpus Christi from Houston and when I got out of the car my glasses fog up!
Steve
2001 U320 40' IF$ Build #5798
2018 Jeep Grand Cherokee Trailhawk Toad
2015 GMC Duramax HD2500 Toad
2014 Polaris RZR 1000
Litchfield Park, AZ- Soon to be Paulden, AZ

Re: Dash Air

Reply #13 –
Rick, with the resonator if you will put a couple of layers of fiberglass wrap around it the condenser should not have a problem  ours has worked out fine
Chris
1999 U 320 DGFE
Build Number 5523
Chris & Elka Lang
In the field, Lonoke AR

Re: Dash Air

Reply #14 –
One thing I will add to this topic... Get the 3m clear UV protectant tint (its clear so calm down)

I put it on all the windows in the coach .. wow what a difference ^.^d ..

Re: Dash Air

Reply #15 –
I drove a 280 for 11 years without dash air..My 270 blows air in the 30's and when it quits I will do what ever it takes to fix it.. Once you know how well one can work I wouldn't want to be without it.. I live in a hot and humid climate and travel a lot in the same... Much cold air is a beautiful thang.
Dub McBride 1996 270
 

Re: Dash Air

Reply #16 –
Quote from: Bob and Julie –
Phred, I live in Corpus Christi Texas. Very high humidity here. Doesn't matter what I do, the moisture is there. But you're right about air infiltration. Need to get that better. PO took out the propane fridge but didn't seal up the vents well. Plus the exhaust fan in the kitchen let's in air too. ...

So my fridge has been having a lot of condensation lately. Its a 12 volt marine fridge put in by Paul Smith, 2 previous owners ago. Noticed some black mold at the base, so decided to take it out and clean under and around it, cause I just don't have enough to do.... and found that there is a ton of wet warm air coming in behind it. Glad I pulled it out. Will have to do a better job of sealing it up. The fridge uses a danforth compressor which is remotely mounted on a shelf next to it. Need to get better air flow to the compressor and less air out, since there is no propane there anymore.
'99 U320 40 WTFE
Build #5462,
1500 Watts Solar 600 amp Victron lithium
2012 Jeep Grand Cherokee Overland Hemi
Instagram bobfnbw
Retired