Dash Air not Cool

[mypopslou]

On my 2016 Tuscany Coach with Cummins 450, the dash air has never really been too cold, actually more cool than cold. I just added Freon to the system. I put about 16 oz in, with the capacity being 2.5lbs or 40 oz. Gauge I used to insert Freon has the green area which ranges from 25 to 50. When I finished adding what I did the air coming out of the dash was colder than it has ever been and the gauge was reading about 33, 34 in the green. 

Did I put enough in or should I add some additional. I saw the warnings about not overcharging the system.

Any help would be appreciated

[wolfe10]

At what ambient temperature,  and verify that the condenser fan was running? Low side PSI (what you are reading) IS temperature dependent.

What was temperature at the return (inside coach) and what was temperature at the center vent with the fan on high, engine at 1,200-1,300 RPM?

[mypopslou]

Brett, temperature here in Florida is 88, condenser fan was not running when I first started adding Freon but did come on and was running through the remainder of this process. I believe the low side (blue cap) is where I connected hose and gauge and after adding 16 oz it was reading 33 in the green on the gauge. I do not know the exact temperature coming out of the returns but the engine was idling most of the time, I did increase the rpm for less than a minute and the air coming out was significantly cooler than when I started.  

Obviously I have no idea how much was in the system when I started which has lead to my question about 33 on the gauge and did I do enough.

First time I have tried this with my motorhome, have done it with my wifes car in the past.

Thank you

[txiceman]

Mypopslou, I recommend you get professional help rather than depend on the internet.  You can easily do more damage that will cost you more than a certified A/C tech.

Ken

[rayin]

FWIW, I had the same problem when we bought this MH in 2013. I bought a large can of refrigerant that has the gauge showing low/OK/high. I  added refrigerant until the gauge was in the middle of the green/OK. Ever since the dash air has measured about 40-45°F, regardless of outside temperature.

I can't ever recall reading about someone ruining their auto air conditioner with the self-use containers.

Edit: This utube video tutorial was informative to me.

 

[wayne77590]

Listen to TXicman. He is a certified refrigeration guy.  What chassis do you have. I have Freightliner so I took mine to the Freighliner place. They determined it was a leak. Replaced what had to be replaced and the problem was solved.  Prior to that I took it to two garage (mechanics) and the fix they did, did not last.

[dickandlois]

The low pressure side should be no higher then 30 to 35 lbs. on the low side of the gauge set.  To high and one gets into high pressure issues that can get real expensive quickly.

Rich.

[wildebill308]

Rich, the problem is he isn't using "real gages" he has one of those charge kits with just a color coded gage. If it is in the middle of the green and cooling ok he should be ok. When it leaks down again I would take it to someone who can do a proper leak check.

Bill

[rayin]

A reference for auto-type air conditioning and using refrigeration gauge set: : https://www.btrac.com/documents/svc-manual-revision-i-feb-2011.pdf

[dickandlois]

On 5/24/2020 at 4:30 PM, WILDEBILL308 said:

Rich, the problem is he isn't using "real gages" he has one of those charge kits with just a color coded gage. If it is in the middle of the green and cooling ok he should be ok. When it leaks down again I would take it to someone who can do a proper leak check.

Bill

Bill, Sniffers and UV dye work will when looking for those nasty little leaks!

Rich.

[txiceman]

The worst leaks to find are the evaporator cores.  You have to use a sniffer at the air outlets on the dash.

Ken

[wildebill308]

8 hours ago, DickandLois said:

Bill, Sniffers and UV dye work will when looking for those nasty little leaks!

Rich.

When you need to know, use a helium leak detector. 

https://heliumleakdetection.net/what-is-helium-leak-detection/

I use to have one at work. 

The OP may be lucky as the stuff he used has a sealer in it and it might fix the problem for the season. 

Bill

[huffypuff]

2016 hmmm  Did you put R134a into a R1234yf  system?  Also where is the condenser.  If in the rear 40 feet away the efficiency is loss from that distance.  If you got cold air while driving, consider yourself lucky.   

[mypopslou]

Thank you for all your help, I put R134A in the system as that is the type of refrigerant listed on system. The gauge read 33 when I was finished and I had cold air coming into coach. I have not driven it yet but hope that it is better than it was.

Thanks for all of your help 

[dickandlois]

1 hour ago, huffypuff said:

2016 hmmm  Did you put R134a into a R1234yf  system?  Also where is the condenser.  If in the rear 40 feet away the efficiency is loss from that distance.  If you got cold air while driving, consider yourself lucky.   

Ray, The 2 Freon's are compatible. The difference is price and 1234yf is flammable. Because of the molecular structure the compressors tend to run cooler, but a spark can light the 1234yf. Not much of an issue in Diesel coaches, but I do wonder about gas powered vehicles as the ignition systems age. There is a flammability warning in the safety data sheet. Some AC Compressor builders are using a different PAG oil for the 1234yf.

Rich.  

[huffypuff]

4 hours ago, DickandLois said:

Ray, The 2 Freon's are compatible. The difference is price and 1234yf is flammable. Because of the molecular structure the compressors tend to run cooler, but a spark can light the 1234yf. Not much of an issue in Diesel coaches, but I do wonder about gas powered vehicles as the ignition systems age. There is a flammability warning in the safety data sheet. Some AC Compressor builders are using a different PAG oil for the 1234yf.

Rich.  

When I got certified on the new refrigerant we also had a class and a test to be certified.    If you top off a A/C unit with r134a  in a r1234yf  unit you contaminate the system which is illegal.  

Please read number 6 in the link.  

https://macsworldwide.wordpress.com/2016/10/24/keeping-the-facts-straight-on-r-1234yf/

[rayin]

On 5/27/2020 at 12:53 PM, DickandLois said:

Ray, The 2 Freon's are compatible. The difference is price and 1234yf is flammable. Because of the molecular structure the compressors tend to run cooler, but a spark can light the 1234yf. Not much of an issue in Diesel coaches, but I do wonder about gas powered vehicles as the ignition systems age. There is a flammability warning in the safety data sheet. Some AC Compressor builders are using a different PAG oil for the 1234yf.

Rich.  

Speaking of flammable, the ideal refrigerant would be propane-if one could live with the obvious drawback.(pun intended)

[mypopslou]

HuffyPuff, there is a label on the front of my system which states it uses R134A, so I did not mix the two

[huffypuff]

8 hours ago, Mypopslou said:

HuffyPuff, there is a label on the front of my system which states it uses R134A, so I did not mix the two

Good deal, if it was a car or light truck 1234yf would be what it have.  

On 5/28/2020 at 12:13 PM, RayIN said:

Speaking of flammable, the ideal refrigerant would be propane-if one could live with the obvious drawback.(pun intended)

Yes it would work but lots of cars would have flaming crashes.  

[dickandlois]

2 hours ago, huffypuff said:

Good deal, if it was a car or light truck 1234yf would be what it have.  

Yes it would work but lots of cars would have flaming crashes.  

That is what concerns me about adding more flammable items to a hot closed area. Seeing more vehicle fires in the  years sense high pressure  fuel injector systems where installed and a lot of low quality fuel lines to save every dime from the base cost. Add all the touch screen controls, that take ones eyes off the road and they are more dangerous then cellphone detraction's. IMHO ! A number of the touch screens have a message that using them could cause an accident and if the information is true and one taps the message so you can make adjustments to any of the setting. All that that action does is make the driver accept all legal actions and protects the manufactures from liability.

Rich.

[manholt]

Rich.

I have "Trip Tek".   When you turn on the back camera, the computer comes on and it has a disclaimer on the screen, then you have a check list of everything from disconnect coach to TPMS.  Takes about 5 minutes to scroll thru everything, then the cameras come on...all 11 of them, including 4 radar's, that's the VORAD anti collision system!  Then you can put it in Drive and go!

Where the danger comes in, is while your driving an alarm goes off, 99% of the time it's been high temp on TPMS,  2 choices....pull over, scroll to TPMS and hit reset, that kills the alarm or do it while driving!  Most would not pull over!!!  I have found that the TPMS is pre set by the manufacturer, I can reset the P but not the T, the T is set at Ambient temp of 85 +/- 20!  I guess the 25 year old nerds, forgot to enter road heat/cold! 

I have contacted Newmar  and got the cost for upgrading system to 2019.  The VORAD will be replaced with one that I have the choice of on/off...TPMS will be PMS.  The new Trip Tek, is user friendly, you get an alarm it switches to that screen so you don't have to find it and Linda can take care of it or me if she is driving!  Lot's of other things will also be taken care of on their dime!   

The 2012 Silver leaf system was replaced by a 2017 System by previous owner and we love it. 

[rls7201]

The ignition point of 1234yf is over 700°F

 

Richard

[mypopslou]

Thank you for all of your responses on my question. We left home on June 1 and the dash air has been working great, almost 4,000 miles so far and it is blowing cold so the amount I put into the system must have been acceptable. As we continue our journey I will let you know if anything changes but again thanks for your help and support.

[rayin]

5 hours ago, Mypopslou said:

Thank you for all of your responses on my question. We left home on June 1 and the dash air has been working great, almost 4,000 miles so far and it is blowing cold so the amount I put into the system must have been acceptable. As we continue our journey I will let you know if anything changes but again thanks for your help and support.

I'm glad you are cool again and hope it continues for a long-long time.