Removal of the rear A/C

grozier

Member
Hi all,

As hinted on the Yahoo board, I have removed the rear Kerstner air conditioning unit from the roof. I have driven through and parked in enough rain to be able to recommend this, but as always, your mileage may vary!

This air conditioner was originally designed for delivery vans and thus is not optimized for noise or comfort. Early NAFTA James Cooks apparently came with a smaller unit originally, but these were swapped out in the U.S. at some point before sale. Perhaps that was a quieter air conditioner, but it was apparently outgunned by Texas and Florida heat.

In any case, we had no need for this A/C since we hardly ever used it and, living in Europe, don't have access to 110V shore power. So off it went, all 60 kilograms (~130 pounds), not including the components in the closet.

I was very curious to see how the handling would change after removing the A/C. The improvement was dramatic, and perhaps a better change than switching to the Koni dampers. On undulating roads, there is significantly less "head toss." On the highway, side winds and the bow wave of trucks still push the van around, but there is only the initial movement, easily corrected, instead of the sway, followed by counter sway, etc.

Removal is pretty much as per the manual, with the following additions: (if you don't have the manual, get it, because I do not cover the steps here in sufficient detail to do this job safely without it.)

  • I removed the interior cabinet without an assistant, but I would recommend having one if at all possible.
  • Protect the counter tops in advance. The scratches in our van are clearly from an earlier removal, either to replace the unit or repair the evaporator drain hoses.
  • I removed the "hat box" and the lamps in the cabinet, even though the manual does not call for it.
  • After loosening the six allen bolts (M8, 6 mm head if I recall correctly) I pushed up from below to help loosen the unit before lifting it.
  • Hoisting eyes are provided on the unit. You will need a suitable hoist (ours was rated 500 kg) and a secure anchor (ours was a huge tree). Remember that you need to lift the unit almost two feet higher than its installed position to clear the bath skylight. Then, after driving the van out from underneath, you need to be able to get it down to the ground. It is a long way!
  • The roof is not designed to be stepped on. Be careful.

After removing the A/C, you need to patch the hole. The rough-cut hole is approximately 58x40 cm. It is not perfectly square. The roof is approximately 2" thick. Above this rough cut is a plastic flange that the A/C engages. On our van, a sheet of 8mm polycarbonate, 595mm x 425 mm, with 50 mm radius corners, covers the lip well. It is attached with self-tapping screws and a healthy bead of Sikaflex. The 8mm sheet is overkill in terms of toughness, but you don't want it to bow under the weight of water, snow, or ice!

In retrospect, I might have removed that plastic flange and patched the roof directly, as there are some hairline cracks in the flange that I did not notice until after the repair. Ideally, you will do this operation under a covered spot so you can decide for yourself. If you remove the flange, however, you will have to contend with the slight curvature of the roof.

Inside, I fitted a good chunk of polystyrene insulation, then placed a 3 mm acrylic sheet (63x39 cm) in place with self-tapping screws and duct tape. Note that the rough-cut hole extends slightly under the cabinet, at least in our van. This sheet cannot be much more than 39 cm in the front-back direction without being an interference fit that could cause squeaks. You can see most of this with a good flashlight after removing the vents from the cabinet and peering in through the narrow door in the bathroom.

You will need six plastic bolts (M8x20mm) to replace the metal bolts that held the A/C in place. Out of an abundance of caution, I also covered these with duct tape. Ugly, but on the roof so not visible.

Then there is some housekeeping of the remaining wires to prevent shorts and rattles. Presumably you will not replace the 150 Amp fusible link, but a future owner might, and that cable is hefty enough to be a major hazard if it ever went live. You'll also want to close off the evaporator drain (I made a simple wye with the remaining hose) and, if you're ambitious, you'll fix the air pipe for the exhaust fan. (I did not.) No wonder it does such a poor job, as it is squeezed nearly flat as it comes up behing the pantry!

An additional benefit to this job is you get a nice new linen cabinet!

Here are some photographs.

Next up is to get the other components out and investigate the feasibility of turning the water heater cabinet into a propane locker with the space that becomes available.

Ted
 

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OldWest

2004 T1N Westfalia
Thank you, especially for the photos.

A dilemma--hate driving West in windy conditions but do like AC in hot/humid weather. Europe & Australia have split air systems for RVs so not all weight on top. Also, the American units are 90-100 lbs so slightly lighter. When AC becomes unrepairable, will have to decide.

Solar panel would be easy to out in that location. Run wires down corner where kitchen fan duct is. Could even hinge panel and have a second skylight.

Eternabond tape is not too bad to patch holes (used small pieces to cover TV antenna mounting holes until glued solar panel on top. Vinyl plasticky part of tape may release from sticky stuff though--that is what happened to take around Fantastic Fan.
 

OldWest

2004 T1N Westfalia
Was that a wood frame inside opening for ac or just some type of insulation? Was there access with ac unit removed to add insulation in rest of area between fiberglass top and inner ceiling?

Fred had laminated his upper cabinet white to cover holes. Could also use the self-adhesive stainless steel stuff for appliances. Also saw some self-adhesive metal tiles at Home Depot but heavy. If tall, could put an erasable writable strip to cover vents.
 

512Westy

Member
Nice job with the write up and useful information. Very interesting comments on the handling improvements. Hope it doesn't get too hot over there this summer! :)
The pictures are a real aid if any of us need to tear into ours in the future. I noticed that your unit has the cut off shielded cable where the drain hose, power cables, and exhaust duct drop down next to the cabinet. I had just run a thermostat cable through that area a few weeks ago when I added a digital thermostat, and had stuck my I-phone into the chase and took pictures to confirm what opening space was available. I guess that made it an eye-phone. I'm sorry, i couldn't resist. Anyway, I saw that cable and have no idea why it's there. Anyone know what that abandoned cable is from? It is visible in "to clean up" picture.
 

onemanvan

Member
Ted,

Many thanks for the excellent/detailed write up on A/C removal.

I have been toying with the idea of swapping out that heavy beast (Kerstner) with a swamp cooler. I mostly travel out west ( where the humidity is typically low [hence good swamp cooler country]). Armed with your pictures and dimensions I am more confident than ever that the Solar Chill Truck Cool might drop right in as a replacement. The base of the Truck Cool is about 20" wide and the length is about 15 1/2" ( the fan shrouds poke out an additional 2 1/2"). I'm thinking about just dropping the base of the swamp cooler into the hole and then add a couple of those swivel ducts to get the cool air down through the roof and into the van. I'm also thinking about yanking out the generator and putting a 20 to 30 gallon water tank in it's place (swamp coolers are thirsty). I would probably only fill the tank up when I get to a destination campsite so I'm not carrying around unnecessary weight.

If any of this makes any sense I'd appreciate your opinion as to whether or not you think this sounds like it might work?

John...

http://www.southwest-solar.com/productcatalog/item.nhtml?profile=productcatalog&UID=145

 

OldWest

2004 T1N Westfalia
As apparently many Westies have this piece of cable, would guess that maybe was intended for something. Other end dangles down behind black tank.

If only in the first few Westies, would have guessed that Airstream put in for the TV or antenna, but then changed their mind and routed wires differently.

But as apparently pops up on later numbered Westies, maybe an option for antenna, cable, TV? Looks like that kind of cable but don't know.
 

OldWest

2004 T1N Westfalia
Not answering for Ted but just chiming in.

1. Price as compared to American ac unit.
2. Power usage is considerably lower but still maybe too much of a drain on batteries alone (and if need to plug in, why not go for ac unit). Or if delete generator then need more batteries?
3. Weight advantage? If lighter on top, then great but if need a source of water (gallon per hour?) Then maybe consider type of camping.
4. Type of camping. If plugged in and water source, then pros of evap cooler would be less weight on top? Energy savings would not matter as plugged in.

If dry camping a lot, pros would be less power usage (but still maybe too much for batteries) and still need water?
 

OldWest

2004 T1N Westfalia
The photo of ac flange reminds me of the flange for the big skylight. If the flange were in good condition,, wonder if a skylight cover might fit over the flange--and either figure out hinges or some other method to keep in place. Add gaskets. The skylight cover would overlap flange so no leaks as long as flange doesn't lrak. Same with a metal framed solar panel where metal frame would overlap flange. Just idle thoughts.
 

grozier

Member
  • I have no experience with swamp coolers, but interesting that the unit in the link was designed for Big Rigs. The 15 1/2" dimension will be tight if you want to retain the original cabinet and not create new holes.
  • As for the vestigial vents and metal grate in the existing cabinet, I think they do a nice job of providing cross-through ventilation in the linen cabinet. We can also open the bath vent to its "latched" position, then leave the narrow door open. On the road, with cab A/C going, the drying line in the bath should be more effective with its new "breeze" going by. In the past, we have had to prop the whole bath door open for this.
  • I looked for some time for a "lid" to mate with that flange. Unfortunately I came up short. I also wrote Kerstner to see if it was their part but got no response. I think the optional Euro kitchen skylight was further forward and the same 40x40 as the bath. The rectangular Heki Midi is too big to fit the hole: http://www.dometic.com/enuk/Europe/...cles/Rooflights/products/?productdataid=69742 . Perhaps a Fantastic Fan would work well?
  • Yes, there seemed to be wood bracing all sides of the hole, if I recall correctly, and limited, if any, access to the top to add insulation. I think the air gap probably provides very good insulation for the size. Additional material might conduct more heat and/or retain condensation?
  • That cut off cord is indeed a mystery. The TV antenna is the most plausible answer. A long shot is that it was intended for the original FM antenna or optional phone antenna. Early Westy prototypes seem to have one integrated into the high roof. See below. In any case, it's worth keeping there if only to make chasing a future wire easier! This was certainly the case with the phone jack and the rear fog light I had to add per German rules.

Ted
 

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grozier

Member
Almost a year later, I finally got around to removing the related equipment below the closet.

The twin Mean Well converters, Kissling relay, cooling fan, case, and other hardware total 22 kg, just shy of 50 pounds. This doesn't count the wiring from cabinet to roof and cabinet to front of van. I these in place in case we ever want to add a 110- or 220V air conditioner; having the 12V back there for an inverter would be useful, and the 12V to the roof should make for a good chase line...

It is good to be able to finally seal that big hole in the floor and hopefully reduce the dust entry into the van!

I will put the converters on eBay because they seem to have a commodity value. Is anyone interested in the other items before I chuck them out? If so, please make a reasonable offer by PM and don't forget $$$ shipping from Germany!

Best regards,

Ted
 

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GA Westy
A magnum inverter fits nicely in that space. I have an ms2812 and I pulled the 2/0 wire from the rooftop and dropped it into the house battery bank. Then I installed a battery switch beside the inverter. It works well.


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GA Westy


A tight squeeze but definitely doable. Save the cooling fan. You can use that to vent the space and keep the inverter from overheating.


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grozier

Member
Nice setup. Have you wired the inverter into the main 110V system?

Why Westfalia/Airstream didn't do the following, I have no idea: (would have been cheaper, easier, lighter, more reliable than the factory system)

- High idle kit instead of generator (keep spare wheel)
- Big sine wave inverter like yours instead of tandem 12V converter
- Same ATS30 line/generator switch
- Generic 110V-12V battery charger with proper load curves (unlike custom Cherokee unit)
- 110V Dometic or equivalent A/C unit on roof (cut a hole further forward and reinforce roof; preserve towel storage cabinet with access from bath)

With this setup, you would have all the same functionality as the version we got, plus:

- Much longer off-grid runtime
- An air conditioner designed for sleeping people, not fresh fish
- A system that US techs would be able to understand and repair if needed
- 110V when driving down the road (for charging cameras, laptops, etc.)

Ted
 

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GA Westy
I have it wired into the main breaker. Then did a dedicated ac wire to the kitchen cabinet and put in double outlets.

I don't have high idle in place yet but the system does work on generator, alternator and shore power.

I installed a dometic penguin 2 11000 btu, heat strip and digital thermostat that has cool, heat and furnace. Planning on wiring the furnace wire to the espar.


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GA Westy
Grozier, the magnum actually has a great battery charger built in. I already disconnected the Cherokee charger.


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GA Westy
We just dismantled a Kerstner A.C. From another westy today. Anyone need Parts?




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grozier

Member
Great. Is that one of the earlier vans? I notice that it doesn't have the (ill-fitting) black metal shield above the hob.

Did the white A/C surround crack during removal? Perhaps we were lucky that ours didn't. It meant we could cap the hole with a flat polycarbonate sheet instead of having to match the contour of the roof.

Ted
 

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