Date: Sat, 4 Jun 2016 01:03:43 -0400
Reply-To: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Subject: Re: Road Trip problems
In-Reply-To: <25533221.564443.1464994271286.JavaMail.root@tvweb133088.mailsrvcs.net>
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The radiator fan is operated in a medium speed when the Condenser pressure is too high and needs to be brought down. This is controlled by a pressure switch on the AC that operates a relay on the fuse box. During hot weather especially with low speeds it is normal for this switch to increase the speed of the radiator fan. The problem is worsened by a system that is overcharged. It is normal for the fan to run at this speed for some time after the AC or the engine is shut down, especially if the radiator is hot as that heat will soak into the AC condenser and keep the refrigerant at the higher pressure. 5 to 20 minute fan after runs are not cause for concern during these conditions.
Some things that can help include having all the deflectors in place for the radiator to make sure air is forced through. This includes the cardboard pieces on the grill. Make sure the AC is properly charged. The system has to be filled by weight and especially with R134a you can’t top it off only using gauge pressures. You need the tools to calculate charge based on superheat and even that changes with inside and outside temperature. Proper charging requires full evacuation (recovery) and refill by weight. ~1,300 grams. Turning off the AC just before reaching your destination will allow the condenser to cool off with the help of the sir being pushed through while driving. It is also helpful for the engine and cooling system to let the engine idle down for a minute or so before turning it off to reduce the heat soak boiling the coolant in the engine.
Dennis
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of David Bjorkman
Sent: Friday, June 3, 2016 6:51 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Road Trip problems
Hi All;
Having a great time crossing the country on Rt. 66. But now I'm stuck in Holbrook AZ. On the way back from the Painted Desert/Petrified Forest Nat. Park, it got hot out,so I decided to try the A/C. Don't use it much-very rarely, in the Northeast. Before leaving I put some ProSeal in it and had it charged. Well it worked fine. Cooled down as much as a Westie does, the bus didn't seem to mind, temp gauge steady on LED, but when we got back to the motel (laundry day) the fan seemed to be stuck on high. I am somewhat aware of the switch that does that when A/C on. Stuck on not for a few minutes, but about 20 minutes. During which time (worried about battery discharge) I started and ran the bus a couple of times and turned the A/C on and off. Nothing worked. So I decided to pull the #1, 30 amp radiator fan fuse. It was a melted mess. While contemplating disconnecting the battery, the fan shut off. Currently, I've picked out the plastic parts of the fuse, but the metal parts are stuck in there. I have power to both sides of the fuse, ignition on or off. The fuse and holder next to it seems to have no damage. Here is the question. Affordable German in Phoenix, 100+ miles away, will take a look tomorrow. I have power to both sides of the (gone) fuse, will the fan work properly (no A/C) so that we can get up real early and drive there, or should I leave it to a tow (AAA). Maybe that's a dumb question, but I would like to know what thoughts anyone has.
Dave B.
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