a/c install do you need a negitive vac

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Jul 15, 2011 | 08:59 PM

#26

DCFIVER

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From: Looking for SloMofo....

Re: a/c install do you need a negitive vac

Quote:

Originally Posted by dem0nk1d

http://www.harborfreight.com/catalog...?q=vacuum+pump

harbor has a cheap one that you use with your compressor, but i heard you really need a compressor to keep up. **on sale for 12.99**

they also have a more commercial type of pump which is electric for 100 bucks. and with the 20% coupon you can get a great deal i would think....

manifold gauges for 50.00
http://www.harborfreight.com/catalog...result?q=a%2Fc

Those pumps are worthless for an AC system. You need a minimum of 5-7 cfm to properly vacuum down an AC system. Once you get into the 7cfm range you are talking $300-$400 dollar vac pumps. Overkill for one time use i suppose. At the very least you want a 5 cfm pump, then. Still over $200 for a good pump. In the end it would be cheaper to take it to a shop....

Jul 15, 2011 | 09:10 PM

#27

Organization

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Re: a/c install do you need a negitive vac

Quote:

Originally Posted by DCFIVER

Oily flush is very bad. You will never get it all out. The best flush is liquid refrigerant, but that is pricey and most shops wont bother doing it correctly because it is cost prohibitive to the customer. Admittedly, we dont. So the next best alternative is something like this
http://www.4s.com/Problem%20Solving%...I/Content.aspx
it evaporates fairly quickly and only a minute amount will be left over, unfortunately it is corrosive and can damage seals and the orifice tube(doesnt apply to you obviously) it is not common but it CAN happen, however it is a hundred times better than any "oily" flush you may use.

what about brake cleaner

Jul 16, 2011 | 04:54 AM

#28

fcm

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From: kelowna, bc, canada

Re: a/c install do you need a negitive vac

Quote:

Originally Posted by Organization

what about brake cleaner

Absolutely not, can you say hydrocarbon. 94

Jul 16, 2011 | 08:22 AM

#29

Organization

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Re: a/c install do you need a negitive vac

just asking

Jul 16, 2011 | 09:21 AM

#30

fcm

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From: kelowna, bc, canada

Re: a/c install do you need a negitive vac

Just answering. 94

Jul 19, 2011 | 08:44 PM

#31

dem0nk1d

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From: SD Thief KiLLER, ca, thief killer

Re: a/c install do you need a negitive vac

Quote:

Originally Posted by fcm

Yes a vacuum is needed, I would run a vacuum pump for at least 1hr on any A/C system that has been "open", this will insure any moisture in the system is boiled off.

I flush out compressors all the time, pour flush into the suction side, rotate clutch clockwise as you drain the flush, repeat a few times, and make sure all flush is drained when finished.

When reinstalling put 2oz of C4 oil in compressor and split the remaining oil charge, [Ester oil] between the compressor and the filter/dryer, assemble, a nitrogen pressure test @ os should be done at this time, the longer the better, but at least 1 hr.

If pressure holds, 1hr on a vacuum pump, close valves on gauge and let sit for 5min, if vacuum holds recharge system. 94

you state using a mix of C4 oil and ester. i have not seen this c4 compressor oil, only PAG.

Jul 20, 2011 | 06:14 AM

#32

fcm

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From: kelowna, bc, canada

Re: a/c install do you need a negitive vac

http://www.southsidecontrol.com/acat...4_07_6112.html We use 2oz of this on any retrofit, [into compressor] and for lubing O rings and seals.
We use Ester oil because it is compatible with most A/C systems, it will "tolerate" trace amounts of mineral oil left in retrofitted A/C systems, it is less susceptible to air contamination then pag/mineral oils.94

Jul 20, 2011 | 06:20 AM

#33

dem0nk1d

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From: SD Thief KiLLER, ca, thief killer

Re: a/c install do you need a negitive vac

Since the system is a true 134 and really not a retrofit can i just use the ester oil on the o-rings and PAG 46 in the rest of the system? Also looking into the Honda Factory service manual it doesn't have the measurements for R134a system, only R12.

Jul 20, 2011 | 11:48 AM

#34

fcm

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From: kelowna, bc, canada

Re: a/c install do you need a negitive vac

Use Ester oil in the system and to lube the O rings I will get you the oil and refrigerant charge for a 95 Civic as soon as I get back to work from lunch. 94

Jul 20, 2011 | 12:48 PM

#35

fcm

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From: kelowna, bc, canada

Re: a/c install do you need a negitive vac

If you use PAG, use PAG 46 and it is 5oz, [also 5oz if you use Ester oil] the refrigerant charge is 19oz of R134a. 94

Jul 20, 2011 | 12:50 PM

#36

dem0nk1d

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From: SD Thief KiLLER, ca, thief killer

Re: a/c install do you need a negitive vac

thanks very much i'm look forward to having a/c soon. i'm too old now to be driving in the heat.

Jul 21, 2011 | 08:23 PM

#37

dem0nk1d

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From: SD Thief KiLLER, ca, thief killer

Re: a/c install do you need a negitive vac

so epic fail today the lines i got from the junk yard are off a R134A 94-95 Civic, and once i was ready to hook up the Lowside line to the compressor it wouldn't fit. =( So looks like the only solution is head to the junk yard and grab a 92 R12A a/c lowside line and hope everything works afterwards. Sucks! Put so much time.... Also now i can't close the system since that lowside line doesn't bolt into the compressor. Do you think i should be fine once i get the correct line? Or will i have to clean / flush all the current work again?

Jul 21, 2011 | 08:33 PM

#38

dem0nk1d

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From: SD Thief KiLLER, ca, thief killer

Re: a/c install do you need a negitive vac

56221 Suction; OE# 80311-SR1-A12
56222 Suction; OE# 80311-SR3-A02

So it looks like there are two different hoses... This was listed under the 95 civic at 4 Seasons eCatalog. i have both suction hoses, but totally different ends that hook into the L side line, that goes to the EVAP... So i can't even swap the suctions hoses. Dizzle!