Excavator a/c

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Al9
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Joined: Tue Mar 10, 2020 3:26 am

Re: Excavator a/c

Postby Al9 » Thu Apr 09, 2020 4:54 am

Good to know. Mine came from a Kia car. Hyundai part number 97604-17001. Manufactured by Daehan Koki. Delphi SP10 fixed displacement swashplate compressor. The orifice's diameter makes me think of a 1.5 TR rated valve. The fact that it's still open a little once the disc is like -22F, on the default setting, makes me think that it's cross charged.

Never pressure tested or equipped one of my valves on an actual system so i can't tell you if the o-ring will still be good or not once you tamper with the nut.
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bohica2xo
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Location: Las Vegas, NV

Re: Excavator a/c

Postby bohica2xo » Thu Apr 09, 2020 6:59 am

Since the manufacturers make hundreds of different valves from that same piece of aluminum extrusion, it can be very easy mix them up.

For instance the Denso 4752004 looks like that. Used in Acura, Cadillac and Honda, common in the UA. While Toyota used the Denso 4750107 valve in nearly everything from the little MR2 to the Land Cruiser. Yet the Denso 4750511 only fits 2 years of Scion Xa /Xb.

Is there a part number stamped on the original valve anywhere?

Sounds like the CV on the valve is too small. It can regulate properly only at low compressor rpm.
H8theheat
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Joined: Fri Apr 03, 2020 3:37 pm

Re: Excavator a/c

Postby H8theheat » Thu Apr 09, 2020 7:02 am

This valve has a part number E41620-0222 from doosan. It's $40 I'm tempted to just replace it...there is ALOT of crap behind the seat you have to take apart to get to it, it is about a 5-6 hour job start to finish.
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bohica2xo
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Re: Excavator a/c

Postby bohica2xo » Thu Apr 09, 2020 8:33 am

Sorry to hear about the labor on that one. Heavy equipment is never easy.

Interesting. That part number takes me back to a 2003 - 2006 Kia Sorrento.

Which would make sense, given the common country of origin, and probably a similar cabin volume.
H8theheat
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Joined: Fri Apr 03, 2020 3:37 pm

Re: Excavator a/c

Postby H8theheat » Thu Apr 09, 2020 1:29 pm

Just out of curiosity what would be an acceptable vent temp it's 85 or so right now and I just want it to be able to keep up when it's 95.
Al9
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Joined: Tue Mar 10, 2020 3:26 am

Re: Excavator a/c

Postby Al9 » Thu Apr 09, 2020 1:56 pm

I'd say 41F, or 42F at most. Above that, it's highly likely you've got a problem somewhere (mostly either a ridiculously low refrigerant charge or a worn compressor), even though it will still appear to provide some cooling (but 46F at vent tends to feel rather warm in my experience). Get below that, and things may become uncomfortably cold, even if the evaporator fins manage to not clog up with ice. In 100F weather, my car manages to bring interior down to a comfortable 72F on full recirc, 41F at vent. Cooking thermometer (never use IR thermometers for vent temperature).
H8theheat
Posts: 9
Joined: Fri Apr 03, 2020 3:37 pm

Re: Excavator a/c

Postby H8theheat » Thu Apr 09, 2020 2:54 pm

Thank you for all of the help
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bohica2xo
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Location: Las Vegas, NV

Re: Excavator a/c

Postby bohica2xo » Thu Apr 09, 2020 8:16 pm

In any mobile system anything above 33f is good for discharge air. As long as you can keep the evaporator from building up ice you are good.

Here in the dry air of Las Vegas I run a second switch with a very low setpoint for quick cooldown. Evaporator temps fall below 30f, but at 8% humidity & 115f ambient this is not a problem.

With the hysteresis in CCOT systems you can run an average evaporator temperature of 33f without ice buildup. With a TXV system the evaporator temperature sensor handles the job. Just make sure that at it's lowest setting, with the cabin fan on lowest speed that ice formation is not an issue.

A19 apparently is an HVAC guy. This is MVAC. If you can hold your hand in front of a vent and make your knuckles hurt the system is working well. That is why there is a temperature dial and fan speeds.
Al9
Posts: 77
Joined: Tue Mar 10, 2020 3:26 am

Re: Excavator a/c

Postby Al9 » Fri Apr 10, 2020 1:40 am

I described how my car's VDC+TXV system works. That's the most it will attain with a blue (42+-1 psi) MCV fitted inside. It will never give you vent air that is colder than 41F. And it will sense discharge pressure, use it to control how cold the evaporator will get and give you 41F at vent only in really hot weather even though you still have a good charge, will basically act like you flipped your second switch on. Likely set up that way to account for Euro weather, which can get really cold and humid in the winter and will be much more humid than Las Vegas in the summer, likely leading to a frozen evaporator. When that one failed and started starving the evaporator up, needing a replacement, i wanted to try fitting a lower setting purple or yellow control valve instead of the original blue one (now uniformed to an even warmer brown one at OEM for some reason), but since i don't have the equipment i would've had to pay someone again to professionally recover and recharge the system in case it led to a frozen evaporator in milder weather. That said, i feel comfortable enough with my car's AC at the moment. OP basically wanted to know what is a comfortable temp.
H8theheat
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Joined: Fri Apr 03, 2020 3:37 pm

Re: Excavator a/c

Postby H8theheat » Wed May 06, 2020 11:52 am

Alright I'm back and I have the same problem. I have replaced the expansion valve again and I still cannot get colder than 49-52 out of the vent..I cleaned the evaporator again so air flow is not an issue...one thing I am wondering about is the little sensor on the evaporator I think it is called a frost sensor or an evaporator sensor, what exactly does it do and where on the evaporator should it mount ?

Things done so far

Heater valves are shut
Ac lines Flushed
New compressor with right amount of correct oil and weight of refrigerant (30 oz )

New drier
Expansion valve replaced twice
Evaporator fins cleaned and installed new filter
Condenser fins cleaned


It's 87 outside and in the cab it's 78-80

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