Author Topic: calibrated orifice DFS2A  (Read 9342 times)

Offline patvac

  • VIP Member
  • Member Since: May 2009
  • Posts: 18
Re: calibrated orifice
« Reply #15 on: June 05, 2009, 03:22:54 PM »
high       Low

165         40

150          25

150         23    (psi)





Temperature external of evaporator 49.5F at 23 psi   (shoud be -2F)

Temperature external of condenser 97 F at the fan at 150 psi (shoud be -82.5F)



Fitting at the condenser are full of ice and evaporator his starting to fill up too.



Thank you

Offline patvac

  • VIP Member
  • Member Since: May 2009
  • Posts: 18
Re: calibrated orifice
« Reply #16 on: June 05, 2009, 03:25:32 PM »
The top part of the evaporator his freezing faster and with a lot more ice than the bottom one

Offline Icehouse

  • Technician
  • Member Since: Oct 2008
  • Posts: 569
    • hvacbob
Re: calibrated orifice
« Reply #17 on: June 05, 2009, 04:53:51 PM »
high       Low

165         40

150          25

150         23    (psi)





Temperature external of evaporator 49.5F at 23 psi   (shoud be -2F)

Temperature external of condenser 97 F at the fan at 150 psi (shoud be -82.5F)



Fitting at the condenser are full of ice and evaporator his starting to fill up too.



Thank you

Where are you getting your information from ? The evaporator is internal (inside the room) and condenser is external (outside the room)
Those pressures are too low for R22 period
NATE, NCCER, PHCC,HVAC Certified Instructor
Member RSES, US Army Refrigeration Specialist(Retired), Former Refrigeration Teacher NYC Board of Ed.
a tragedy has happen to me : http://web.me.com/zenzoidman/Bobice/

Offline JWWebster

  • Technician
  • Member Since: Jan 2008
  • Posts: 8780
  • Country: us
  • SublimeMasterJW
    • Buy me a beer through paypal
    • JW's Sublime Appliance Advice
Re: calibrated orifice
« Reply #18 on: June 05, 2009, 07:33:06 PM »
Brang yer low side pressure up to 68.5 PSI and see if that don't fugging git it right. verify it by checking the amp draw.
May the hinges of our friendship
        never grow rusty.

About the icons: The beer is tip link, if a tech saves ya some money buy em a 6 pack. The small green square=personal message. The green dot is a link to my web page on appliance repair and other general BS I love to post. The letter sends me email.
I love fan letters! LOL

Offline patvac

  • VIP Member
  • Member Since: May 2009
  • Posts: 18
Re: calibrated orifice
« Reply #19 on: June 14, 2009, 09:54:52 PM »
hi, i have try icehouse method and the result make no sens, ( i am probable not doing it correctly). With the help of a friend i have check where i tough they was a restriction. there is notting. We applied vaccum for 2 hours and charge the unit. The unit said 3.1pounds up to 25 feet of refrigerant lines. Is that combine lines or each one (example 25 suction and 25 pressure would make 50 or 25) Because i have 20 on each side and we consider it would make 40 so we add 0.9 oz per 3 feet of pipping. Problem is still there. My friend doesn't  have the tool for the wet temp bulb ( sorry icehouse). I decided to try something. I have covered the partially the condenser with one of my jackets.because the temperature of the air blown by the condenser was similar to the exterior temp. The air now is hotter( Du to the increase of the pressure ) the unit inside is not freezing up any more ( tested only a couple of hours) evaporator temperature is a bit hotter then it was but no more freezing. It Increase low pressure  like one of you asked me. Is my unit over or under charge thank you

Offline JWWebster

  • Technician
  • Member Since: Jan 2008
  • Posts: 8780
  • Country: us
  • SublimeMasterJW
    • Buy me a beer through paypal
    • JW's Sublime Appliance Advice
Re: calibrated orifice
« Reply #20 on: June 14, 2009, 11:15:41 PM »
What are ya working on is it a walk in cooler or a ice machine or central air? WTF is it you are trying to charge? Get the suction pressure up to 68.5 PSI and that will give you 40 degrees F across the a-coil. that is a good thang. If you think the head pressure is getting too high watch your amp meter. This ain't rocket science. O0
« Last Edit: June 14, 2009, 11:22:54 PM by JWWebster »
May the hinges of our friendship
        never grow rusty.

About the icons: The beer is tip link, if a tech saves ya some money buy em a 6 pack. The small green square=personal message. The green dot is a link to my web page on appliance repair and other general BS I love to post. The letter sends me email.
I love fan letters! LOL

Offline patvac

  • VIP Member
  • Member Since: May 2009
  • Posts: 18
Re: calibrated orifice
« Reply #21 on: June 14, 2009, 11:22:25 PM »
i think you guys call it a mini split. 12000btu a/c unit where the condenser is outside to ground level and the evaporator is on the second floor

Offline Icehouse

  • Technician
  • Member Since: Oct 2008
  • Posts: 569
    • hvacbob
Re: calibrated orifice
« Reply #22 on: June 15, 2009, 01:29:21 PM »
When evacuating the system with both high and low side hoses connected to the compressor,
1.Open high side hand wheel on gauge manifold.
2.Leave low side hand wheel closed on gauge manifold. Start vacuum pump.
3.Observe low side gauge (should go into vacuum).
4.If it does not go into a vacuum reading, you have a restriction.
5.Continue operating till you have reached 29" hg. vacuum although using a micron gauge is the proper way (500 microns).
6.Let unit stand for 5 minutes, should be no change.
7.A slow rise indicates moisture (longer evacuation time).
8.Rapid rise, you got a leak.
NATE, NCCER, PHCC,HVAC Certified Instructor
Member RSES, US Army Refrigeration Specialist(Retired), Former Refrigeration Teacher NYC Board of Ed.
a tragedy has happen to me : http://web.me.com/zenzoidman/Bobice/

Offline JWWebster

  • Technician
  • Member Since: Jan 2008
  • Posts: 8780
  • Country: us
  • SublimeMasterJW
    • Buy me a beer through paypal
    • JW's Sublime Appliance Advice
Re: calibrated orifice
« Reply #23 on: June 15, 2009, 02:27:30 PM »
I bet it has something to do with how the pipes connect from the evaporator to the outside condenser. How did you make up the connections?
May the hinges of our friendship
        never grow rusty.

About the icons: The beer is tip link, if a tech saves ya some money buy em a 6 pack. The small green square=personal message. The green dot is a link to my web page on appliance repair and other general BS I love to post. The letter sends me email.
I love fan letters! LOL

Offline Icehouse

  • Technician
  • Member Since: Oct 2008
  • Posts: 569
    • hvacbob
Re: calibrated orifice
« Reply #24 on: June 15, 2009, 03:32:19 PM »
I bet it has something to do with how the pipes connect from the evaporator to the outside condenser. How did you make up the connections?
>:( He mentioned that at the start. :tickedoff:
NATE, NCCER, PHCC,HVAC Certified Instructor
Member RSES, US Army Refrigeration Specialist(Retired), Former Refrigeration Teacher NYC Board of Ed.
a tragedy has happen to me : http://web.me.com/zenzoidman/Bobice/

Offline patvac

  • VIP Member
  • Member Since: May 2009
  • Posts: 18
Re: calibrated orifice
« Reply #25 on: June 15, 2009, 09:43:01 PM »
1/4 size pipe for pressure(copper)
1/2 for succion (copper)
they are shape like an Z but on the side

Sorry if i misconduct you
If needed i can add a picture

Offline JWWebster

  • Technician
  • Member Since: Jan 2008
  • Posts: 8780
  • Country: us
  • SublimeMasterJW
    • Buy me a beer through paypal
    • JW's Sublime Appliance Advice
Re: calibrated orifice
« Reply #26 on: June 15, 2009, 09:55:30 PM »
Please add a pic because this is all becoming perfectly clear now. Your tubing is too small. The minimum is 3/8ths tubing for the hi side and 5/8th for suction.
« Last Edit: June 15, 2009, 09:59:06 PM by JWWebster »
May the hinges of our friendship
        never grow rusty.

About the icons: The beer is tip link, if a tech saves ya some money buy em a 6 pack. The small green square=personal message. The green dot is a link to my web page on appliance repair and other general BS I love to post. The letter sends me email.
I love fan letters! LOL

Offline Icehouse

  • Technician
  • Member Since: Oct 2008
  • Posts: 569
    • hvacbob
Re: calibrated orifice
« Reply #27 on: June 16, 2009, 04:37:41 AM »
Please add a pic because this is all becoming perfectly clear now. Your tubing is too small. The minimum is 3/8ths tubing for the hi side and 5/8th for suction.
  :) JW, he is giving "Nominal" size which is inside diameter. Air Conditioning uses outside diameter  which is larger by (1/8). Therefore 1/4" ID is 3/8" OD and 1/2" ID is 5/8" OD.
NATE, NCCER, PHCC,HVAC Certified Instructor
Member RSES, US Army Refrigeration Specialist(Retired), Former Refrigeration Teacher NYC Board of Ed.
a tragedy has happen to me : http://web.me.com/zenzoidman/Bobice/

Offline Icehouse

  • Technician
  • Member Since: Oct 2008
  • Posts: 569
    • hvacbob
Re: calibrated orifice
« Reply #28 on: June 16, 2009, 05:05:51 AM »
Let's look at "old school" charging. That is "Ambient Temperature" plus 30. Convert this reading using a "Pressure-Temperature" chart to pressure. Example 80*F + 30 = 110* F. Assuming the refrigerant is R-22, you will read 225# (actually 226.4).
Low side reading should be equivalent to 40* F evaporator temperature, in this case 69# (actually68.5).  O0
NATE, NCCER, PHCC,HVAC Certified Instructor
Member RSES, US Army Refrigeration Specialist(Retired), Former Refrigeration Teacher NYC Board of Ed.
a tragedy has happen to me : http://web.me.com/zenzoidman/Bobice/

Offline Repair-man

  • Technician
  • Member Since: Feb 2008
  • Posts: 3020
  • Country: us
  • The Virtual Repairman
    • The Virtual Repairmans Appliance Help
Re: calibrated orifice
« Reply #29 on: June 16, 2009, 05:20:28 AM »
Since he is dealing with very low ambient temps, this system may not operate correctly under 68 degrees outside. He really needs a heat pump capable of defrosting itself.
"It's only expensive if someone else fixes it for you" -
The Virtual Repairman   www.repair2000.com