| Author | Message | ||
| Henry 96A3 (Hank)
Registered Member Username: Hank Post Number: 81 Registered: 11-2005 Posted From: 69.129.126.133 Rating: N/A |
My factory OTR AC has given up the ghost. I bought a nice basement heatpump and will probably end up gutting the stock AC when I install it. It does seems kind of silly to run a generator to run the AC while driving but from all the stuff I've read it sounds like keeping your factory AC alive is a lot more expensive in the long run. My question is, how do I get AC for the defrost? I was thinking about keeping the stock evaporator that's up front and maybe plumb a small compressor off the engine to run it? Anyone done that? Is there a better way of doing it? Thanks, Hank | ||
| Chris Peters (Chris_85_rts)
Registered Member Username: Chris_85_rts Post Number: 20 Registered: 11-2006 Posted From: 66.194.150.45 Rating: N/A |
I am often surprised how people will pay thousands of dollars for a genset, and then use it as little as possible. I do believe it is true that unless you are an A/C guy, it is better to scrap the OTR A/C. I have two roof airs, and having a big enough inverter to run both would have cost as much or more then the genset, that was going to buy anyway, so why not run the genset. As for the defrost, my bus has a heater upfront that blows on the windows, but my front A/C also can blow directly on the windows, so for now, I did not need additional A/C up front. I think one problem with using the stock evap up front and new compressor in the back, is matching the system components and running the lines. Probably better off buying a completely matched system from a place like Cruise Air and then running lines of a size they recommend. | ||
| George M. Todd (George_mc6)
Registered Member Username: George_mc6 Post Number: 158 Registered: 8-2006 Posted From: 207.231.81.59 Rating: N/A |
Hank, I am an A/C guy, and I have done it. It is actually fairly easy, and well worth the effort to have driver's air, not to mention dry defrost. I am puzzled by the "running the lines" post, as they are already there, as is the front evaporator, and all the controls, etc. If your bus is using R22, I would NOT change to R134a. Instead, I would get a replacement compressor for an older car or truck that used R12, and use "Hot Shot" replacement refrigerant, swap the TXV, and enjoy. This stuff is EPA legal, and uses the same oil as 22, which is important. Also, this stuff has larger molecules, and won't permeate old refrigeration hoses, o-rings, etc. All of the commercial refrigeration dealers use it, or one of the other R12 replacements. If your bus uses 134a now, no brainer, stay with it, the hose and o-ring material is made for small molecules, and the oil is right. George | ||
| doug yes (Dougg)
Registered Member Username: Dougg Post Number: 19 Registered: 1-2007 Posted From: 71.29.142.20 Rating: N/A |
Where can Hot Shot be bought at a good price? | ||
| David Hartley (Drdave)
Registered Member Username: Drdave Post Number: 774 Registered: 5-2005 Posted From: 72.189.203.211 Rating: N/A |
Defrosters use heat, no a/c ( generally ). ( late model cars & trucks use heat/a-c to dehumify the defroster air ) Keep your drivers heater and defroster. You can remove the a/c coils from under the dash. They are usually separately installed with a common fan system for both. Just box the heat coils. Dave.... | ||
| Nick Badame Refrigeration Co. (Dnick85)
Registered Member Username: Dnick85 Post Number: 111 Registered: 2-2006 Posted From: 68.45.178.44 Rating: N/A |
Hi Hank, I personally am a favorite in keeping the OTR air. Theese systems are built to last a long time and if you are in need of repairs, then there alot of us that can help you out. Just like all other parts on a bus, they will cost you a bit for repairs but, they will well outlast the type system you want to install now. If you decide to gut it, then George Todd has given you good advice already. Good Luck Nick- | ||
| Henry 96A3 (Hank)
Registered Member Username: Hank Post Number: 82 Registered: 11-2005 Posted From: 69.129.126.133 Rating: N/A |
Thanks for the input everyone. The more I think about it the more I agree with Nick about keeping the OTR air. I've read the archive wars on the topic. It really did work great when it worked. It is a R134a system and the charter service I bought the bus from said the compressor was fairly new. The other thing is that I hope to have my AC certification in a few years. I'm going to diesel mechanic's school this fall for a two year program and the AC training is part of the curriculum (mainly for reefer service). If I can nurse it along I will hopefully know how to maintain and fix the darn thing pretty soon. The main condenser coil located on the driver side just in front of the front luggage bay has some bad corrosion on the fins. And, is that wet area a leak?  Replacement condenser coils are ridiculously expensive new. Is this bad enough to warrant replacement? Thanks, Hank | ||
| Chuck Newman (Chuck_newman)
Registered Member Username: Chuck_newman Post Number: 195 Registered: 1-2005 Posted From: 63.145.177.245 Rating: N/A |
Henry, I have a '90 102A3 that I'm going to pull the entire OTR AC system later this year. And it works. The condenser is corrosion free. When finished, I'll post all on WOBN'S THE FLEA MARKET. Free to anyone who picks it up. All leftovers go to the dump. | ||
| Henry 96A3 (Hank)
Registered Member Username: Hank Post Number: 84 Registered: 11-2005 Posted From: 69.129.126.133 Rating: N/A |
Chuck, Thanks for the heads up. I'll keep my eyes open for that. Hank | ||
| George M. Todd (George_mc6)
Registered Member Username: George_mc6 Post Number: 159 Registered: 8-2006 Posted From: 207.231.81.59 Rating: N/A |
Hank, I should have said that I too am in favor of OTR air, and I'm glad you have decided to keep it. Oil travels with the refrigerant, so a leak will look dirty and or oily most of the time. The oil will gather dust, and the leak usually doesn't look wet. Does your bus have an ac HI/LO light? If it is not on, and the bulb is good, you may be just low on charge, and not enough low to trip the pressure switch. Your bus should have a clutch type compressor? Check for 24V at the coil, if the clutch is not engaged. If the clutch engages, does the suction (large) line on the comp get cool? Thats a start, tell us what you find, and we'll help you through it! George | ||
| George M. Todd (George_mc6)
Registered Member Username: George_mc6 Post Number: 160 Registered: 8-2006 Posted From: 207.231.81.59 Rating: N/A |
Chuck, I'm right down 65/70 in Auburn, just off of Wise, and if I can't talk you out of keeping the otr air, I will gladly help you take it out carefully. Hopefully your condenser and Hank's are the same shape, and would fit, if thats his problem. Anyhow, would you either e or phone please, when you want to do it, or before to say hi. George Todd 530 823-7913, C 916 257-0279, toddelec@psyber.com | ||
| Henry 96A3 (Hank)
Registered Member Username: Hank Post Number: 85 Registered: 11-2005 Posted From: 69.129.126.133 Rating: N/A |
George, Well, the AC idiot lite was burned out and once I replaced the bulb, it came on. The compressor clutch does not kick in either so it seems like I might be low on freon. The compressor oil level is okay. It's been raining today so I haven't had much time to fool around with it but I'll see what I can find tomorrow. Hank | ||
| Nick Badame Refrigeration Co. (Dnick85)
Registered Member Username: Dnick85 Post Number: 112 Registered: 2-2006 Posted From: 70.208.72.114 Rating: N/A |
Hi Hank, Glad to hear that you are concidering leaving the OTR Air. Sounds like a pretty simple fix so far. [small leak, low on refrigerant] Maybe you might know someone with a leak detector or mix up a solution of bubble soap to test that condencer. The rotted fins are not as critical on a bus as they are on a home system. The condencers are much heavier guage copper. If you do locate a leak, you can even scrape away fins and have the condencer coil brazed. Let us know what you find, I'm sure between George and myself, we can get you up and running. Nick Badame- | ||
| George M. Todd (George_mc6)
Registered Member Username: George_mc6 Post Number: 165 Registered: 8-2006 Posted From: 207.231.81.59 Rating: N/A |
Hank, With the light on, the clutch will not engage, as the system is locked out, almost certainly for low freon. So, ignore all the rest of my advice, you have a leak. From what Nick says, he must have brazed as many coils as I have, and its not a big deal. George |