Update: May 2023
The Enviro-Safe product has done a great job plugging the leak as the dash AC still works fine. I do start the Dash AC on Max cool for ~15 minutes but after it is outputting very cold air, than I can just operate it normally. See article below…
August 2022: It’s strange, but all the times I’ve worked on the Dash A/C, I’ve not published a specific article about it. Probably just put it in a general travel section article. I’m just as surprised as you are. Probably. This article corrects that issue, puts it in the repair section and covers from around Spring of ’18 to ’22.
The dash air worked fine for almost the first 2 years I owned this Journey, February 2016 to 2018, but then I am a snow bird now and try to time my trips so that I don’t need A/C or heat while traveling. Doesn’t always work out that way though and in July 2018 I did notice that the dash air wasn’t as cold as normal. Ambient temps played a roll in the confusion about proper operation the previous months, but this time I was sure it wasn’t working right. Was arrived at and was staying in Wendell, Idaho at the time so checked with a local automotive shop.
They do work on RV’s so drove the RV over there. The tech hooked his machine up to my system and judged it to just be low on Freon, after it running for 30 minutes.
I saw the gauges and they stayed in the ‘normal’ zone for the entire time after he had topped it off. I paid, and off I went just 3 miles to the RV park to park. So that short trip wasn’t much of a first test.
A week later, it was time to head south, and when I turn it on during that trip in the late afternoon it worked well. But the next day, not as well. Then day after that, pretty obvious that it wasn’t working right. By then I was down in Parker Arizona and I know that it’s not good to run the compressor with the Freon level low, so I cautiously avoided turning it on during my travel to Mexico and down to Mazatlan. And then one day after returning to the US, I wasn’t paying attention, and accidentally switched it on. Quickly turned it back off several minutes later when I noticed. Dammit.
Anyway, heading back north around March 2019, the serpentine belt breaks, (the link will take you to my article about it) and it’s because of a frozen compressor idler pulley. GAH! I don’t know if running it with low/no Freon caused that but…
So I had that all repaired in Parker Arizona with a new compressor installed. The shop that I was at doesn’t have the AC equipment needed, so I just had some oil put inside the compressor before the tech installed it on the engine. And I had them leave the electrical connection unconnected so the compressor would never run until I was ready. Then I was very careful to not switch the controls to AC (even though the electrical connection was disconnected) while I delayed adding Freon until the shop in Wendell.
It was cool weather, I had other stuff to work on so it wasn’t until July of 2019 that I’m back in Wendell and I have the same shop I was at the last time here in town check things out for me. Explained about the bad compressor replacement. Reconnected the wire, they went to work, filled it with Freon but it wasn’t working correctly, and they suspected a bad expansion valve (shown below), and they did a full purge of the system. And got 1/3 teaspoon of black carbon granules out of the system. They do this purge by creating a vacuum in the system and then forcing fresh clean flushing liquid throughout it. Rinses out the bad stuff. We could not find a new dryer canister at the nearby Freightliner so he cleaned and flushed my old one and put it back into the system. Later I found online ‘generic’ dryers that would have worked. Checked the condenser fans and they are good. Filled it up with Freon, and off I went to spend the night at the RV park nearby. He put in a can of disclosure juice but we didn’t see any stains that indicate a leak the next day. It’s the kind of juice that stains things that can be seen with a black light to tell you where a leak is. But as I said, he couldn’t see any purple stains. Ha! Get it? Purple Rain, Purple Stains? Prince reference there.
Even so, after I left Wendell and started on the journey south with the system all recharged with Freon, didn’t take long driving in the heat to find that there was still a slow leak in the system because the cooling didn’t last long. Maybe worked well 200 miles. Then sorta okay another 200. I trusted his work in Wendell, but his machine is older and probably not as sensitive as a new machine and didn’t show any leak that was obviously there. I had watched the process and the gauges and I agreed. The UV juice ‘should’ have shown something but it must have been the kind of leak that vibration of running on the road and the engine running for hours would show it up. But this RV is a big machine, and he could have just missed it under there when he tried to track the system. Just sitting at the shop running it wouldn’t leak. And he’d flushed the system so there shouldn’t be any carbon granules blocking things.
I was a little worried about things because of those carbon granules the shop had pushed out. The reason goes back to the days when I was a Service Manager at Montgomery Ward. I had the techs tell me about the ‘black death’ when a compressor died, it could put these black granules of carbon into the system which could ruin the entire system by plugging it and the plug could be very difficult to find, so cost prohibitive. If the shop tech had not gotten most of them out of this system, they could easily block a port or connection or even ruin the compressor again. So had my fingers crossed.
Still, while driving and despite all the work the shop had done, there was still a leak and soon I didn’t have dash AC. Oh, I should mention that the shop also added a can of stop leak which didn’t seem to have any effect. So I disconnected the power wire to the compressor again.
Didn’t want to keep throwing money at this problem so I did some research and discovered that there is a Butane/Propane mixture that can be used in AC systems to replace Freon. Okay! I’m on board with this. It’s not a hazard to the environment either. In fact, the name is Enviro-Safe. I’ll call it ES from here on out. AND, because I’m a private party, not an automotive shop or AC business, I can legally exhaust any left over Freon from my private vehicle to the atmosphere. It looked perfect for the job because the molecules are larger then Freon gas so they don’t leak out as readily so they might just plug that slow leak that even a can of Stop Leak didn’t seal. And you don’t need a vacuum pump! How cool is that?
So I bought the kit with the Brass 134a Gauge Set, several 8 oz cans of juice, a can of oil, and eventually an adapter because their gauge kit setup didn’t match the ports in my RV. They might have fixed that problem by now. Here’s a shot of my old bad compressor on the left, and the new one that wasn’t an exact replacement. I did get an exact replacement from O’Reilly’s a couple days later and took the wrong one back to Napa.
Here’s the condenser under that grill. On the drivers side at the rear of the RV. Many RVs have a similar setup. This keeps the condenser close to the AC compressor on the engine so that the run of hoses from the compressor to the condenser can be shorter. A condenser is just a small radiator like item. The fans blow cooling air over the radiator and that causes the Freon (or in my case now, the propane/butane fuel mixture) to change from a gas to a liquid. There is also a drier attached near this radiator, behind it on this Freightliner chassis. There are generics available too. The two fans are controlled by a thermal sensing device up in front of the RV under the hood on the evaporator.
And backing off a bit…you can see this condenser is under the bedroom closet slide on my rig.
Here’s a link to one of the many pages of automotive AC information that’s available: Understanding automobile AC systems.
And below is a shot of where the ES product is introduced to the system. Using the connector under the red cap. This is way up front of my diesel pusher under the small hood that’s there directly under the front windows. The evaporator is under that plastic cover shown in the next picture and the condenser with the drier is back behind the driver’s side dual tires as mentioned earlier. The compressor is attached to the engine of course and the hoses that snake up to and back from the dash are like 50 feet in total. So it uses a lot of Freon or ES compared to a car. The adapter provided by ES is screwed onto that connector and then the ES is sucked into the system by the compressor. There’s no need to evacuate the system.
This is how the setup looked before they replaced that aluminum block, called the expansion valve, and then they also replaced that pressure switch that controls the fans back at the rear of the RV. Here’s the ports under the hood at the front of the RV. On the passenger side firewall. All those aluminum parts, and the two black hoses connected to the pipes are part of the AC system.
The blue and red caps are access to the high side and low side ports. The black plastic cover behind is where the evaporator and the heating system radiator both reside.
This is the setup after installing the new expansion valve and that switch.
Anyway, I attached the gauge and hose assembly that comes with the ES kit, put in a can of oil, and then started adding the 8 oz cans of juice. One of the cans in the kit said it contained Stop Leak and I used it. Each 8 oz can of juice is equivalent (larger molecules) of 21 oz of Freon. And I added enough to equal just shy of 44 oz. I’ve forgotten all the details but the kit comes with instructions and I followed them.
I did NOT need to evacuate the system according to the instructions. First removed the Schrader valve and let it exhaust. Didn’t take long probably due to the slow leak. Then replaced the valve and hooked up the fill hose and gauge, allowed a can of ES to work it’s way into the system, started the engine and set the AC to MAX. The compressor will draw the ES juice into the system just fine that way. I was tempted to drive to a shop and have them reclaim the Freon first but I knew because of the leak there wouldn’t be much anyway so I just exhausted it to atmosphere.
What I found was that my system started to cool down after the cans were added but seemed a bit below optimum temp so I added one more partial can after the first two. This was a couple years ago so I’ve forgotten some of the details so be sure to carefully read your instructions that come with the ES. And keep any open flame away at all costs.
After the ES was fully installed, I’ve had several occasions to use the AC for hours at a time on the road. And since install, the system has maintained the perfect amount of cooling at the dash. And I’ve not had to add any more ES. Even on the trip from Tucson to Pahrump it was cooling fine. Check out the outside temp on the road from Tucson to Quartzsite in mid-May of ’22. I had it on Max AC and fan setting of 2 and was very comfortable. It got so hot in the house portion behind me that I started and ran the genset for a couple hours for the heatpump to cool it, but near the dash with the dash AC running, temperature was comfortable. Very comfortable in fact. Wow though, it was 110 F in Quartzsite. I only stayed one night, then used the AC nearly all the next day on the way up to Las Vegas then over to Pahrump where it was cooler, down in the high 80’s. So I’m convinced that the leak isn’t a problem now, and that the ES works great!
ES is a fine product IMO that is both safe for the environment AND plugs up any fine holes you might have in your system (and the Stop Leak they provide probably helps too). With all the trips I’ve taken with it in the system, if it had been Freon it would have leaked out leading to a yearly or twice yearly expense to top it off…but with the ES juice, cooling is fine and has stayed the same for me over time since installation. They say it’s perfectly safe for any and all AC components too. So the next time you think you need Freon, consider changing your AC system over to ES instead.
Note that the Freon in your RV’s system is non-flammable but can still explode if the engine catches fire (engine fires are the most common RV fires and that’s where the AC compressor is). Yes, the ES is flammable, but it’s no less safe then having a propane tank aboard. You know there are certain safety measures you take with your on-board propane system, it’s the same with the ES. It’s not really any more dangerous then your stove, gas fired heaters, or external BBQ grill. Don’t smoke around it when you’re installing it in your automotive AC system and you’ll be fine. Be sure to use the can of Stop Leak too. Try to have your system pressurized and checked for leaks first at a friendly shop where they can evacuate the Freon. Don’t want a big leak wreaking havoc. Check that there’s no AC hose near the exhaust system. Just common sense stuff.
There is some push back with using a flammable compound mixture in an automotive AC system but note these reasons to not be all that concerned:
- You use gas in your engines and it is pressurized at the tank, pushed through rubber hoses from the tank through plastic filters to the engine in 100’s of millions of cars. Often near hot engine components. Yes, it’s highly explosive, but it’s manageable with good practices. Using propane/butane in AC systems is really no different and since the mixture isn’t highly pressurized for AC use, it might even be safer than a gas automobile system.
- RVs often use diesel fuel pressurized from a pump in the front tank, and routed way back to the rear engine, pumped by the lift pump or HEUI to a much higher pressure before injecting into the engine. Then the overage of fuel heads back to the tank. Over 50 feet of hose carrying diesel fuel under pressure. Most salvage yard RVs totaled by insurance companies are there because of engine fires. MOST. (2nd most common reason used to be refer fires, not sure that’s still true in 2022). So to me, using Propane/Butane in the AC system isn’t any more unsafe than using gas or diesel.
- RV’s already have a propane system on board. Routed through copper pipes and rubber hoses from the tank to the stove, backside of the refer, to 1 or 2 floor furnaces, and to the water heater. RV’ers seldom if ever shut off the propane at the tank when they travel, if they did, the refer wouldn’t keep things cool.
- Modern automotive AC systems are highly engineered to prevent leaks of the small molecules of Freon liquid and gas. So it’s made with gas tight fittings, hoses that are thick and impervious to many chemicals and don’t easily leak gases, radiators and condensers designed for Freon, and so on. Propane/butane is actually easier to contain than Freon because of the larger molecules. AC system fittings can leak as much as 1/4 oz per fitting every 2 years. I doubt that Enviro-Safe or similar compound will leak near that much. Calculations suggest no more than 0.095 oz per connection per 2 years. Far to low a concentration to be a concern.
- The Propane/Butane mix is environmentally safe. It won’t cause environmental damage like Freon is known to do.
- Here’s some additional info: Important Info!
- Here’s an older white paper on the subject with historical info on the use of flammable mixtures in AC systems: Performance and Safety of LPG Refrigerants.
So that’s it. Taken as a whole, I don’t see any more safety concerns using LPG in the AC system on an RV then I see from having propane tank and appliances on board, or having super high pressure diesel fuel in pipes on top of a really hot engine. Installing and using Enviro-Safe Freon replacement mixture in an RV’s AC system is low cost, simple to install, and doesn’t require any fancy equipment, like a gauge set or vacuum pump.
I like it, will keep using it, and have put warning labels on the system here and there, for any shops I might happen to go to or for future owners of this rig.