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Tips on changing orifice size on AC or heatpump

Tips on changing orifice size on air conditioners and heat pumps.
A smaller orifice will create these changes
1 - Takes more refrigerant charge to get the same superheat
2 - Increases capacity
3 - Decreases Energy Efficiency Ratio
4 - Increases Head pressure
5 - Increases sub cooling
6 - Reduces suction pressure
7 - Increases Watts and Amps
A Larger orifice will create these changes
1 - Takes less refrigerant charge to get the same superheat
2 - Decreases Capacity
3 - Increases Energy Efficiency Ratio
4 - Decreases head pressure
5 - Decrease Sub cooling
6 - Increases suction pressure
7 - Reduces Watts and Amps

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1 Answer

How the air conditioners give us cool air and how it works?

I am not sure what you are asking, but AC works via physics. There is a refrigerant, that is pumped under pressure until it becomes a liquid, and during that step it gets quite hot. Like when you use a bicycle pump, the bottom of the pump gets hot where the air compressed.
So, this liquid is run through a condenser, and is much hotter than ambient air, so it gives off heat. On a car, on front of the radiator, on a window unit, outside.

Then this refrigerant is routed through an expansion valve or orifice. This reduces the pressure and the liquid changes into a vapor and is MUCH cooler. Similar to discharging an aerosol can, it becomes cold. So then the refrigerant is routed through an evaporator, similar to a heater core in a car (location wise). Then air is blown through this evaporator and temperature is transferred to the refrigerant.
Then it gets compressed and the cycle continues.

Dec 07, 2010 | Whirlpool ACQ062XJ Air Conditioner

1 Answer

How to add Freon to a Air Conditioner or Refrigeration System

I disagree with your stament "Heat Pumps are very sensitive to either under or over charging. The only correct way to charge a heat pump is to evacuate the system and weigh in the correct charge." weighing it in is not the best way to make it perfect on a heat pump system (weighing in method is for sealed small refrigeration), superheat and subcooling with a manufacturers charging chart displaying wetbulb or drybulb relationship to charge, some manufactures even specify the use of the approach method. Charging should always be done in cooling and line sets must be dead on right size and never exceed 50 ft in length. Charging mainly just needs to be done by a professional never ever anyone without experience or knowledge, its a dangerous chemical (any of them) that can cause injury, also important is making sure you have the correct metering device and that all heat pump systems are an ahri match.

Aug 18, 2010 | Refrigerators

1 Answer

furnace ices up,lines ice up,water condensation leaking in to duct work

1.check filter if really dirty change
2. check Refrigerant if low get charged by a tech
3. check the evaporator coil if dirty clean

Oct 16, 2008 | Heating & Cooling

2 Answers

converting aan LP oven to gas

In most cases the pressure regulator has to be changed or adjusted. The orfices on each burner, oven, broiler and surface burner may need to be changed also. Sometimes they can be adjusted. Sometimes the threads on the pipe are different also. This is to prevent accidental connection to the wrong fuel. The big difference is the gas pressure. LP is usually around 10 - 12 lbs and natural gas is usually around 3 lbs. Properly adjusted you will like natural gas much better than LP as it is slightly hotter. The information will be in the instruction book and also on the Jenn air web site. Whirlpool owns both Maytag and Jenn aire so check all sites. The conversion kit is usually less than $50.

Apr 20, 2008 | Equipex PZ-330 Electric Single Oven

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