Discussion Starter • #1 • Sep 28, 2009. He did, however, say that sometimes both lines of a home heat pump system are insulated for good reason. It’s to prevent the cold suction line from absorb outdoor heat. Find a place where you can touch that pipe, and you'll see that it's still cold. A suction line should be __ to prevent moisture in the air from condensing on the cold tubing. Vapor is recommended to insure one does not flood the compressor with liquid and potentially damaging the compressor. In the cold storage installation, the balanced connection and insulation of the refrigerant piping are very important. Both fans were running But compresser was not. The suction line is always insulated in split central air conditioner unit. It is important that you have a pressure-temperature chart with R-22 on it to follow the rest of this train of thought. The large refrigerant line should feel cool/cold to the touch if the system is operating correctly. To the novice: The truth is that the cold suction line has already left the inside ac unit. • Cold air going out = condensation • Warm air in= energy. liquid filling method: because it is best to use liquid filling liquid refrigerant charging much faster than with gaseous refrigerant, charging on the liquid line need to have a charging valve. Ensure adequate refrigerant velocity in the suction line by making it proper size, not oversize. Heat doesn't flow from cold to hot, so if we want to get the heat out of that refrigerant and put it into 95° F air, we've got to increase the temperature. Some systems have a sight glass that lets you observe the high pressure side and it should not have bubbles or anything but liquid. Many of us have been taught when adding refrigerant to a system, this should be done by adding vapor refrigerant into the suction line. This is the refrigeration effect taking place and the drier and liquid line can even get cold enough to allow frost to form. You can't get rid of heat from a cold refrigerant to 95° F air. If we go outside, we should see it. It’s hot – yes, I did warn you! In order to prevent any contaminants into the system due to negligence. I have a R410 mini split. As indoor air is forced over the evaporator coils, the cold liquid refrigerant in the coils absorbs heat from the air. 2.0 In the event of leakage, brine is more acceptable than refrigerant. Despite conventional wisdom, refrigerant doesn’t get “used up.” That means if you’re low on refrigerant, you have a leak. m/n: CK49-1b s/n: 9606033390 I am not sure how to look up the tonnage of the unit. I have been reading and it could be that the unit is low on freon or a restriction on the line. Under normal operating conditions, the refrigerant should be superheated by about 8 to 12 degrees F so that the vapor leaves the indoor coil at between 48 and 52 degrees F. The superheated vapor is then returned to the compressor through the larger copper line. The suction line should feel cool or mildly cold, but not overly icy cold. Is it normal for the liquid line to be cold next to the air handler. High viscosity oil (as measured in evaporator condition) is more resistant to return by refrigerant flow. The Freon flows through the copper lines to get from indoor unit to outdoor units. The bare and small copper lines are known as liquid lines. Now they’re not necessarily all that way but that’s how a lot of them are. The other is that the compressor is the pump that moves the refrigerant through the system. This LP side should be cold as hell. There's also some tables of high pressure vs low pressure for a volume of refrigerant that should be consulted. Unlike R-22 where refrigerant can be added in either the liquid or vaper state, blends like R-410a MUST be added in the liquid state only. Unit came on and cooled but liquid line was very cold. When your refrigerant line is frozen, your indoor evaporator coil is probably also frozen. Hello everyone, Two days ago, my attic unit was making crashing noises to the point where air flow completely stopped. That's one reason why we need the compressor. This is the misconception that most all my customers have. This refrigerant is much more efficient for an air conditioning system than the water example; the pressure will remain above atmospheric pressure and the boiling refrigerant will not create large amounts of vapor, so a small compressor can be used. We will lose efficiency by not insulating the suction lines. The refrigerant going from step 1 to step 2 is in the insulated copper line. If the liquid line feeding the filter/drier is 105 °F and the shell of the filter/drier cold to the touch, the high side restriction will be obvious. The evaporator coil holds refrigerant, which is a liquid or gas that absorbs heat from warm air. Refrigerant line is not cold, Compressor issue? However, the warmth shouldn't be excessive. Low-pressure refrigerant has the potential to __ heat. Blower Wheel replacement issue? A thermistor or thermocouple on the liquid line about 12 inches before the entrance of the TXV should not be colder than the ambient that surrounds it. The warmth is coming from the compressor, and it's normal. Flare fitting leaked so I pulled all the gas out and fixed the leak , Put it in a vacuum and weighed in the charge. So anyway, it is the real thing. Simply running your hand along the liquid line and on the filter drier may find a local cold spot. This phenomenon is caused by the migration of refrigerant in the lines, boiling off… Several performance issues and signs point to low refrigerant: Loss of cold air inside; Higher-than-usual indoor humidity ; A/C running for long periods; High electricity bills; Ice buildup on the interior coil and refrigerant line leading outside; Hissing or bubbling noises; Low refrigerant levels almost always mean a leak in the line somewhere, and simply adding refrigerant is illegal. Now let's know the cold room refrigerant pipeline. If we were to touch it, it would feel cold. This is commonly referred to as the suction line, but it is also called the return line or vapor line. The liquid line gets less colder as you go outside. When the refrigerant reaches the end of the evaporator, it's a cool vapor. I was unable to find a continuation of his discussion on your site. In an air conditioner that line is called the suction line. feet. By the way, don’t touch the small copper lines. Every winter we receive inquiries about refrigerant lines (in particular, the liquid line) either “sweating” or “frosting” inside the house when the weather gets very cold. It’s a low pressure flash gas line which is why it will sweat. The instantaneous evaporation of liquid refrigerant when it enters the evaporator is called the __ Flash Gas. I’m just using that to demonstrate expansion line is actually the real thing. The smaller uninsulated line typically carries a warm liquid. A compressor is designed to draw in __ refrigerant from the evaporator. So your small line is the cold line and then it’s because it’s actually not a liquid line at all. 1、 Refrigerant line … 90. Refrigerant lines insulation should be also installed properly at furnace plenum (ductwork inside the house) penetration, to prevent condensation / water from dripping onto the furnace enclosure and heat exchanger. Recommended by dry filter to add liquid. (That’s right; AC units don’t really “add cold” to air; they actually “remove heat”!) Discuss refrigerant suction line and liquid line, difference in diameter, difference in temperature, suction line is insulated, liquid line is not insulated. On 2019-03-24 by (mod) - Ahmed it sounds as if you found the problem - a sticking TEX (TXC or thermostatic expansion valve) On 2018-08-10 by Ahmed. Insulated. The refrigerant has to be warmer than the outside air. To be able to go through these four stages effectively and efficiently, a refrigerant should possess certain properties. The larger line typically carries a cool gas and is insulated. Ice on your refrigerant line is the #1 sign of a leak, but here are some others to pay attention to: Higher-than-normal energy bills; Air coming out of your vents isn’t very cold Suction pressure was about 120 and 37 degrees. Low-pressure Vapor. The temp sensors are monitoring the compressor discharge temp, the saturated refrigerant temp in both coils, and the temp on the refrigerant lines exiting both the condenser and the evaporator coil. If the suction line is below freezing (32F) or not within the correct temperature tolerance range for the specific unit, this indicates low pressure in the line. Refrigerant Line Temperature Wrong. Absorb. If your refrigerator is working properly, it should be cold inside and there should be warmth behind or underneath it. After investigating, some of the blower wheel blades were broken and broke the wheel in general. Place a thermometer in a discharge duct. That indicates a possible problem with the compressor, and if so, you'll probably notice the temperature inside the refrigerator going up. Well I went away for awhile and came back later. Condenser coil. This cold liquid goes to the evaporator and the whole cycle repeats again. 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