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Drcool, HVAC Technician
Category: HVAC
Satisfied Customers: 2086
Experience:  i have been an A/C tech for the past 12 Years. working on window types, split type, and package
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I repaired a leak on a unit model AS18AORCF I hadded the 40

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I repaired a leak on a unit model AS18AORCF I hadded the 40 ounces that they were recommending BUT the low side pressures were close to the freezing temperatures of R 22 which was arround 60 PSIG I do have about 16feet line which is what they say is standard The other thing that I found different then the LG systems that I am use to is the condensers fan never really went fast. I had a delt t of about 40 on condenser is this ok. Another situation was that the compressors suddenly stopped the service manual tell me this is to stop the inside coil from freezing . Should I force charge until temp/pressure on low,side gives me 40'F ( 69 PSIG withe refrigerant 22) or shoul I just let it go. Sorry about all the question
Hello.Sorry you are having problems. My name is XXXXX XXXXX I will do my best to help.Please wait to leave rating until we are finished.Is the unit icing at the 60psig and what is the indoor temp and outdoor temp when you have the 60 psig?
Customer: replied 3 years ago.
First are you familiar with these units. If you are is it abnormal for the condenser fan to run at a low speed . The delt T outside was 40 I.e. 75 ambient and 115 coming out by fan. Temperature inside was 49. But if you are familiar with these units you will know that the condenser will stop so no freezing happens at coil so to answer your question there was no freezing. So the basic question is should I put more refrigerant into the system even thoug I weight in the required ounces by the specs and is it normal for condenser fan to run slow I.e. is there a delt range in which the condenser fan will speed up
I have not worked on this particular model Samsung mini split. I have seen some that the condensing fan runs slower than what we are used to seeing. I am going to open to other experts who may know the Samsung model a little better. Please wait to leave rating until you receive a satisfactory answer.

Before you charged the unit, did you evacuate the system, did you use a vacuum meter and how low were you able to measure the microns before charging it up?

Did you replace the bullet type filter stainer?

Those answers affect the outcome of your unit.

115 F is almost the upper limit as a discharge temp so I am thinking, there could be air left on the system and the filter strainer could be a little bit clogged that is why the suction pressure is just 60 psi.

Do you have the port to measure the discharge pressure?

If the unit would trip off on a freezing evaporator coil, it should indicate an alarm if there is a digital display at the front of the unit.

By the way, where did you get the 49F reading inside? Was it the output air of the unit?
If it is then it is just fine.

Now, to test if the anti freeze is the one triggering the condenser to stop, then you can temporarily remove it from the copper pipe where it is inserted. You have to remove the stainless clip first and please do not pull from the wires of the sensor.

Leave it off the copper tube and observe if it would still cut out or continue to run.

In some models I have seen, the condenser fan is dual speed and the speed is controlled by a temperature sensor located in the condenser coil. If the ambient is cold, it would run the low speed and if it is warm, it would use the high speed of the condenser fan.

Double check the capacitor of the fan too, it could also be leaky that would contribute for the slowing down in case you have a single speed motor.

Customer: replied 3 years ago.
So that you have a better understanding I want you to know that I am a refrigeration air condition mechanic have been doing it for 20 years . What I have not done is Samsung units I do a lot of L G. So what I am looking for is some one that actually has worked with these units especially this older,model to let me known that yes /no it's not write for condenser fan to run slow I.e. is there a delta which fan goes to hi .As you said 115'F is top limit does that mean if goes higher will condenser fan come on OR should it be on at this temp. As for condenser shutting of well evaporator stays on service manual says its o.k. Its to help with inside coils not freezing . The question then is maybe I don't have enough refrigerant even though I put in the required ounces to rating plate using a scale Now my gages shows 60psig in some units that is ok others need to add to bring it up to proper pressure/temperature .THAT IS WHY I NEED ADVICE FROM SOME ONE WHO ACTUALLY HAS WORKED WITH THESE UNITS TO LET ME KNOW,FROM EXPERIENCE THAT MAYBE THERE IS NOTTING WRONG AND THAT IT IS DOING WHAT IT NEEDS TO DO .

I asked those questions just to be sure that you did the required procedure before charging the system.

Since you are an HVAC tech, then I would assume you know what you are doing.

I have seen the electrical schematics of your unit and seems the condenser fan is dual speed but controlled by the indoor unit.

I have installed a couple of Samsung unit, can not remember anymore if it includes this model that you are working on.

I would say there is nothing wrong with your unit. At 60 psi, the evaporator coil would not freeze at all.

Just observe the unit further until it cools the room, or until you observe that the unit is reaching temperature, shutting the outdoor unit off, and would not start to freeze the starting pipe of the evaporator coil.

Regarding the condenser fan speed, I would say it is all fine with an ambient of 75F.

Customer: replied 3 years ago.
Thank you for taking the extra effort. Let me know how I can rate you and give you a bonus for your good work

Just click the accept button after this reply of mine.

Thank you again for always using this service.

Drcool, HVAC Technician
Category: HVAC
Satisfied Customers: 2086
Experience: i have been an A/C tech for the past 12 Years. working on window types, split type, and package
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