Crazy Air Con Idea????

Ben,
have a search on the Waeco site
they have a roof mounted 12V compressor A/C, pretty reasonable current draw...

Would be simple to beef your Alternator battery capacity to cope...
You may need to strengthen the turret but would be possible.

Or, just toughen up and open the window.

I agree you cant go back from belt driven air!!

Steve

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Originally Posted by taff

i'd not caught any of this thread until i received a pm and thought it would be more relevant to post here than replying to pm as a few seem interested.
i need to be careful but i'll write it as factual as i can

that Kool ideas unit that is pictured earlier in this thread is the exact same unit i tried in the 90. i wasn't that convinced on the unit so i made sure it was returnable before i bought it.
i met terry when he was in perth and had a face to face chat about how best to maximise the results.
i built a cargo barrier behind the front seats (def 90) and put on a perspex screen effectively making a single cab and positioned ther condensor just behind my steering guard with the fans pushing air over the unit and obviously when moving - ram air also doing it's bit.
i got the system all charged to correct levels and for some reason it would only blow 'warm' air. - the day itself if i remember correctly was mid/late 30's
i was able to get hold of terry (through a friend who knows him) on the phone and handed him over to the guy who was charging my system.
on terry's advise we charged in more gas and was able to get 1 corner of the evaporater 'cool'.
got terry on the blower again and was told that it was because "i had the fans pushing air into the condensor as opposed to pulling"
no worries says i and jumped in the car, took it up to 90kph (thinking the ram air + the fans "pushing" would more than compensate for them not "pulling".
unfortunately still no difference.
i've removed the unit from the car - given it back and am still waiting on my cash. - i've been told many times it's coming but hey, we'll see!

when i met terry in perth he did say that he had a few problems on some units fitted into trucks and that it was because of some of the plastic lines and that he was going to replace them with copper lines.
i can't comment on wether this has helped the unit because mine had the plastic lines.
i'd also like to add that i think the unit was designed as a system to keep a cab a comfortable temp when a truckie is bedding down for the night. i'm sure that for this purpose it would be ideal, but as a stand alone unit (from my experience) can't cope.

sorry for the long winded reply

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just read what you've been up to, the relevant site, looked at the setup and cracked the maths on it and without knowing how much it was "overgassed" or when the last calibration was done on the gassing system

ok very roughly based on its advertised cooling ability and its power draw its essentially a very very large engle intended to stay in front of an already cool cabs heat absorbsion from the outside. at 7000BTu its roughly 2hp worth of aircon which is what you get in a small car.

from the sound of it you were loosing too much in the line from the condenser to the evaporator. When you just started to get one side cool you had just about flooded the line from the condensor to the evaporator and the pilot tube.

But I think the biggest killer of it would have been the volume it was trying to draw down. It might have just about worked out for you if you'd set it up and got it running first thing in the morning before everything got hot it should had just about stayed in front of the heat soak for a 90.

And I agree changing the plastic lines over for an insulated copper or ally line would have given a much better result.

The reason Im posting this up is because a pair of those units is on the cards for big red when the conversion work starts.

Why not rig up an ammonia based absorbtion type fed off the exhaust heat?:D

Are you not a process engineer?:angel:

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Originally Posted by Dougal

Why not rig up an ammonia based absorbtion type fed off the exhaust heat?:D

Are you not a process engineer?:angel:

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I am supprised absorbtion refrigeration is not used more often. Im guessing the process may be disturbed by the motion of the vehicle and really only effective for stationary installations, anybody know if this is the reason?

Paul

just another thought, What sort of humidity do you get over in Perth? If the humidity is low, an evaporative cooling system might be the way to go, don't need to worry about massive energy requirments for them either.

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Originally Posted by paulthepilot_5

I am supprised absorbtion refrigeration is not used more often. Im guessing the process may be disturbed by the motion of the vehicle and really only effective for stationary installations, anybody know if this is the reason?

Paul

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Well it's used for lots of caravan/camper van fridges. So it must work while in motion.

its more to do with the total overall efficiency of the systems, that and they are pressurized with hydrogen.

they're not super effecient systems to begin with, they dont scale well and lots of motion does upset them a bit.

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Originally Posted by isuzurover

There is little/no room to fit a 2nd AC compressor to a 4BD1 to run both AC and compressed air.

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I have a single stepped plate almost vertical on the Port side of the 4BD1, Sorry I mean left side of the motor, spending too much time on boat forums .... back to the plate, on the bottom of the plate is the AC compressor, in the middle is the original Rangie alternator, on top is the 4BD1 alternator/oil pump.

All works well, still have to setup the top alternator to charge the second battery circuit, when that is going I will have 24 Volts charging, our Warn High mount is 24 Volt.

Glenn

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Originally Posted by Bush65

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I will see if I can call into CoolDrive through the week and see what they have to say.

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The people at the CoolDrive place near me did not know much about the Kool Truck C307.

The price they gave me was ~ $4500 (don't remember if that included gst), and given what has been discussed above I quickly lost interest.

I did pick up some other pamphlets on another, larger electric driven compressor unit - Rencool RDK4

The price they gave me for the RDK4-30 is $2500 inc. gst. I could plumb this in to use my existing condenser, evaporator etc. But I will look harder at fitting one of the belt driven compressors I have, and only go this way if It can't be done.