Perfect explaination . most of the time we no need adjust the differential of the pressure switch , just get the cut in pressure will do . and most people don't know actually the pressure switch it's just like our car , you not necessary to hit all the gas , just set higher than other equipment if you need to set primary ( jockey ) , secondary ( duty ) or 3rd cut in equipment (standby ) etc..
Thank you for the video, would you tell me that when the pressure reaches the threshold e.g 75 and the switch trips, The compressor gets off?? and what happens to the pressure. does it increases or decreases. I have "Johnson Controls P77AAW-9350" pressure switch installed on outdoor unit (condnsor) but i dont't know how to adjust it. kindly guide me @JDNelRefrigeration
The colder your fridge the lower the pressure. The warmer your fridge the higher the pressure. Different gasses work at different pressures. There are 2 ways to find out what pressure to adjust your pressure to, to make your fridge function optimal. 1. If you know what gas your fridge operates on, you can find the pressure and temperature equivilent online. 2. Bypass the pressure switch so that your compressor runs continuously , put a thermometer in your fridge and monitor the temperature. If you reach your desired temperature make a note of your gas pressure. Switch the compressor off. When your fridge has warmed up to the temperature that you want it to start up at make a note of the gas pressure. Now you have your 2 pressures to adjust your pressure switch.
Yes MR J iwas gonna ask you as a qualified refrigeration mechanic on that same question ive asked you what if there is no thermostat at all can i use the low pressure switch to maintain that inside temperature and compare my pressures to my degrees celcius or Fahrenheit just to clear that im new on this field im stil learning iwill be doing my big course soon .im saving money for my trade but ido have the basics as well
@@JDNelRefrigeration Should that not be cut in at 38 psi and cut off at 12 psi or am I missing something. Good video, I never seen a pressure switch adjusted like that with a refrigerant tank.
Hi sir i have a question for you im littlebit lost .so if temperature decreases is it decreases on the pressure gauge too can you clearify me on that .because sometimes youwill find that the suction is low not because of the shord of gas please if you find this
How would you go about adjusting when it is already installed on the refrigerator? Same process but using the compressor to add pressure to the switch?
On some of the compressors you have a service valve with 2 connections and on some of them the pressure switch is mounted to one of the 2connections. If so put your gauge on the 2nd connection and close the service valve but not all the way. Once the compressor starts up the suction pressure will drop very quickly because of the service valve being almost closed and it's easy to see the lower pressure that way. While the compressor is off the pressure will increase then you will just have to wait for the pressure to increase to check the higher pressure setting on your pressure switch.
ok. Thank you very much for your quick response and great description. I believe that is what I have. I will give it a try next week and see how it goes..
On a pressure switch there are 3 contacts which comes from a switch that has a common connection a normally open and normally closed connection. You normally put the AC power on the common connection. On the normally open connection you connect your compressor and the normally closed you can connect a crank case heater or a pilot light which is optional.
You need to have a Test Gauge to set a pressure switch the gauge under use is not calibrated having no validation for accuracy tag on it. Second thing is always set operating pressure with all pressure released. Each time you test start from Zero pressure to desired/ trip pressure and always make settings with out pressure. Use Air as media for setting and not Cylider gas as a media. Ihope you will add my comments please to your method.
You are correct except for the suggestion to use air as the pressure media. Air is full of moisture and can contaminate the system. Nitrogen would be the correct choice
Thank you for keeping us old-hands grounded in the basics. Always good to do that from time to time
Perfect explaination . most of the time we no need adjust the differential of the pressure switch , just get the cut in pressure will do . and most people don't know actually the pressure switch it's just like our car , you not necessary to hit all the gas , just set higher than other equipment if you need to set primary ( jockey ) , secondary ( duty ) or 3rd cut in equipment (standby ) etc..
Thank you for the video, would you tell me that when the pressure reaches the threshold e.g 75 and the switch trips, The compressor gets off?? and what happens to the pressure. does it increases or decreases.
I have "Johnson Controls P77AAW-9350" pressure switch installed on outdoor unit (condnsor) but i dont't know how to adjust it.
kindly guide me @JDNelRefrigeration
The colder your fridge the lower the pressure. The warmer your fridge the higher the pressure. Different gasses work at different pressures. There are 2 ways to find out what pressure to adjust your pressure to, to make your fridge function optimal. 1. If you know what gas your fridge operates on, you can find the pressure and temperature equivilent online. 2. Bypass the pressure switch so that your compressor runs continuously , put a thermometer in your fridge and monitor the temperature. If you reach your desired temperature make a note of your gas pressure. Switch the compressor off. When your fridge has warmed up to the temperature that you want it to start up at make a note of the gas pressure. Now you have your 2 pressures to adjust your pressure switch.
Thanks friend!.....That Helped me out!
Great video. Thank you for showing us.
Thank you for the tip. However, my switch adjustment screws have a safety lock. Soon is I remove the locking plate, I was able to adjust the pressure.
Danfoss tends to do that
Very nice video, this way is much easier that after installing the pressure switch thank you...
Good job
Sir great information which you provided us.thanks for it.
Do you have normally open and normally closed contacts that are exchanged according to the pressure in the system?
Yes you do get pressure switches that are manufactured with normally open and normally closed contacts.
very good explication, the chile instruments tech we appreciate it!
Very informative
Great video
Your video is very interesting. keep it up.
Jd can you assist me with R22 refrigerant cut in 6 degrees cut out 4 degrees the range an differential settings please
I need to know what type of refrigerator this is for? And does the evaporator coil have to defrost all the ice each cycle?
Thank you very good explanation
Yes MR J iwas gonna ask you as a qualified refrigeration mechanic on that same question ive asked you what if there is no thermostat at all can i use the low pressure switch to maintain that inside temperature and compare my pressures to my degrees celcius or Fahrenheit just to clear that im new on this field im stil learning iwill be doing my big course soon .im saving money for my trade but ido have the basics as well
Yes you can use a low pressure switch, Good luck with your course.
What's the setting on the pressure switch for 134a , 17/35 or ?
It depends on what temperature you want & how long of a defrost period you want. For a normal cold room I use cut in 38psi, cut out 12psi
@@JDNelRefrigeration Should that not be cut in at 38 psi and cut off at 12 psi or am I missing something. Good video, I never seen a pressure switch adjusted like that with a refrigerant tank.
@@jimdefilippis9630 yes you are right
Thank you!!! Much Appreciated
Very well explained, thanks
Hi sir i have a question for you im littlebit lost .so if temperature decreases is it decreases on the pressure gauge too can you clearify me on that .because sometimes youwill find that the suction is low not because of the shord of gas please if you find this
A pressure switch is used on a system which has an expansion valve and a receiver tank. Systems with capillarys do not use pressure switches.
Great video sir! Very helpful!
Thanks for the excellent explanation - from India
thanks for the information, what is the appropriate pressure for a walk-in refrigerator and walk-in freezer?
It depends on what type of gas you use and what type of temperatures you require.
Please tell me how to use lp and hp switches in cold room electrical connection
You break the compressor or the relay that controls the compressor through the switch in the pressure switch.
How would you go about adjusting when it is already installed on the refrigerator? Same process but using the compressor to add pressure to the switch?
On some of the compressors you have a service valve with 2 connections and on some of them the pressure switch is mounted to one of the 2connections. If so put your gauge on the 2nd connection and close the service valve but not all the way. Once the compressor starts up the suction pressure will drop very quickly because of the service valve being almost closed and it's easy to see the lower pressure that way. While the compressor is off the pressure will increase then you will just have to wait for the pressure to increase to check the higher pressure setting on your pressure switch.
ok. Thank you very much for your quick response and great description. I believe that is what I have. I will give it a try next week and see how it goes..
How do you wire a pressure switch?
On a pressure switch there are 3 contacts which comes from a switch that has a common connection a normally open and normally closed connection. You normally put the AC power on the common connection. On the normally open connection you connect your compressor and the normally closed you can connect a crank case heater or a pilot light which is optional.
Does this turn on at high pressure and off at low pressure?
It depends on how you wire the connections. This pressure switch can be wired either way.
thank you.
Sir what is problem for my pressure pump my pressure pump is not stop automatically
To test whether the pressure switch is the problem disconnect one of the terminals from the switch and see whether your pressure pump stops.
Thank you for your time.
Thanks for your help i appreciate it
So thnxs
Can i adjust water pressure on that switch??
That switch is designed for gas. There are water pressure switches that are designed for water. Rather use the correct pressure switch.
Goeie video. Baie dankie.
Very good explanation.
Thanks, from João Pessoa, Brazil.
Thanks
thanks dost, really helpful...
every good explanation sir thanks you sir
Thank u...
super
Thank you gentlemen
Seems you got good experience but you should have done it with OFN not refrigerant.
Please correct your video as we can not release refrigerant.
You need to have a Test Gauge to set a pressure switch the gauge under use is not calibrated having no validation for accuracy tag on it.
Second thing is always set operating pressure with all pressure released. Each time you test start from Zero pressure to desired/ trip pressure and always make settings with out pressure.
Use Air as media for setting and not Cylider gas as a media.
Ihope you will add my comments please to your method.
You are correct except for the suggestion to use air as the pressure media. Air is full of moisture and can contaminate the system. Nitrogen would be the correct choice
Thank you, sir
Very helpful.
🙏🙏❤️
Thank you
Good explained
za ok ijrutjf
Amazing
Thanks
Thank you sir.....
Thank you sir
perfect
nice
Nice..Ur demonetisation
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Naand jammer om te pla kan ek asb jou Email adres kry en jou jou foon nommer ek is Pieter Bosch
jdnelrefrigeration@gmail.com 0117824387
too much emotional in face
thank you
Thanks