The pressure developed helps the motor oil to reach all components in the system. Install an in-line filter to prevent re-occurrence. I'll do that tonight. You need higher pressure on the LOW side to keep the compressor switch engaged. Is compressor bad? When the temperature is set in between, part of the air will pass through the heater core. He is also providing training to mechanics and works as a Senior Mechanic of a well-known organization. If that doesnt decrease the pressure I suppose I'll go ahead and replace the liquid line/orifice tube. Pressure RangeLow side: 30 to 36 psiHigh side: 313 to 327 psiIndicationsBoth pressures are TOO HIGHCausesImproper refrigerant chargeDefective expansion valveImproper temperature sensor installationRemedyVerify refrigerant chargeCheck temperature sensor What are the effects of low refrigerant pressure at the compressor or in the system? 1. Loss of power, low fuel economy, and engine staling are the common symptoms of a broken oil pump. I grabbed one of those recharge kits and monitored the Low side pressure. 'Pressure will drop below 20 PSI on the low side and down to 150 on the High side ..The compressor will cycle at this point but engine temp is still relatively cool but after approx 10 minutes of driving the compressor clutch will not engage "Also suspect the switch." Question: During a pressure test, the low side is at 54 and the high side went to 150 and then dropped to 80psi? In this article series we explain how overcharging or undercharging of refrigerant in an air conditioner or heat pump is detected and we list the effects of overcharged or undercharged refrigerant. No. REFRIGERANT PRESSURE DIAGNOSIS at InspectApedia.com - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice. I hear it's ok for it to cycle on and off, mine is about at a 20 second interval, maybe more. High side was about 250. The old systems used a sight glass to charge the systems. It had this problem prior to replacing these parts. Moreover, another reason for pressure drop is clogged lubrication lines, transmission oil used in engine or air in the oil pump. - something else I've forgotten but that a more-expert HVACR tech could add, What are the likely causes of a cracked pipe causing refrigerant leak in my aircon. PSI was around 60 off and 0 when on. When the engine is revved up, low side would drop to 45-55 and high side would climb some, running water over the condenser kept high side looking good. To gauge the pressure, hook up a gauge set to the AC system and record the pressures of both low and high sides. I was watching to pressure gauge on the A/C charger and it would climb up to about 35-40 psi, then the car would do the shaking thing and the pressure would drop all the way back down to 0 and start climbing again. "Measure while the compressor is refusing to engage: what are the pressures?' So you have to refer to the factory legends to learn the identification symbols and then refer back to circuit diagrams to find the splice and ground locations. What The Dash Lights Stay On After Key Is Removed Mean? Sometimes high temperature causes oil pressure to drop. Didnt read anything on here about normal high side but high low side. Ltd., 2010. 4) Blockage on the high-pressure side of the system between the compressor and condenser but before the high-pressure port. You can measure the refrigerants pressure at a given temperature. After the system runs for a while, raise the RPMs up to about 1,500. I also agree with the others that you might consider getting an A/C shop to look at this as A/C work can be a bit dangerous on top of causing even more damage to the system. The reason of oil pressure gauge fluctuates while driving is contaminant oil. The filter looks like a small air filter from a car. Thus, you will face low oil pressure while driving. Answer: Since I don't know what system you have, I have to guess. With the compressor There is a relationship between the pressure in the system and temperature. The compressor clutch stays engaged and the pressure readings stay the same. That saves a lot of time because you dont have to refer back to the component locator or circuit locations. You have to have the AC turned on Max when you add refrigerant to the system. Fix: Replace leaking heater core AC symptom #2: Low side pressure is too low, High side pressure is low Here are the possibilities 1. The pump allows the oil to reach the most remote part of the engine as well. Oil pressure drops to zero is not a good sign. Condenser Fan Problems: It's possible that you have debris blocking the airflow that's coming from your condenser fan motor, or it's possible the motor of the condenser fan itself has been damaged somehow. Turned off AC, and it climbed to what looks like 75PSI well off. AWD Tire Replacement Myth: Shall You Change All Four Tires? Ill try adding more in a little bit, but does anybody else have any ideas? Continue readingat REFRIGERANT PROBLEM TYPES or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX. Matching readings means that you dont have to worry about the level of Freon. Jayanth, Nagaraj. Actual readings will vary according to ambient temperature. Generally, an Engine. The Fora platform includes forum software by XenForo, VerticalScope Inc., 111 Peter Street, Suite 600, Toronto, Ontario, M5V 2H1, Canada. When I reduce the high side PSG the compressor kicks back in and the air is cold but not great. Evacuate the system and recharge with the correct amount of refrigerant. Open the low side valve on the manifold gauge set. On commercial systems (and maybe some residential systems) the reduced head pressure can cause refrigerant oil migration or more specifically, the system may be unable to push oil through the cooling coil (the evaporator coil) until it accumulates as a bolus of oil that suddenly returns in one shot tothe compressor. Try the search box just below, or if you prefer, post a question or comment in the Comments box below and we will respond promptly. Does the pressure go up? Smaller air conditioners or refrigeration equipment whose design does not include a refrigerant accumulator are at increased risk of damage from overcharge, liquid slugging, or oil circulation problems. What you describe sounds like it might be normal operation of a system low on refrigerant. Answer: Sounds like the gauges are not connecting. The pressure at which boiling occurs for the local temperature. If not front ac control problem. There are tools that will replace the valve cores with no r134a refrigerant loss. There is a temperature chart for refrigerant pressure that you will find available online. @Freeman, its not about tonnage. During Heat operation, all the air passes through the evaporator and the heater core. WebThat is the reason why the oil pressure drops to zero while driving. No hot water valve is needed because in cool mode the door closes off airflow through the heater core. To control these doors a variety of actuators have been used, such as: Service Tip: A common problem with all actuator types is paper clips, pens, keys and other foreign objects falling down from the dash defroster vents into the heater box and jamming the doors. In other words, the evaporator core ices up and stop cooling. What happens when the system runs, do the gauges both move? The system is probably leaking. I pulled a vacuum on the system prior to charging. Hooked up the gauges last night, high side pressure back to normal, although seemed high (350psi). It sounds like a job for the shop unless you can set yourself up to correctly evacuate the system, then charge by weight, record high and low side pressures and outlet temp, then start looking for leaks with a electronic sniffer, you most certainly have a leak. Powered by Discourse, best viewed with JavaScript enabled. Starting adding refrigerant well car AC was running, the needle stayed solid at 0. With the system running, place a fender cover in front of the condenser and observe the pressure. "Natural refrigerants for refrigeration and air-conditioning systems." I need shims to increase the 'air gap'; where would purchase the shims ? 98,000 miles If it doesn't pull enough air across the condenser, then the pressures can get really high. - improper brazing or soldering This could be normal if outdoor temperatures are very high. So I'm afraid I suspect the compressor. Answer: Not enough information. Either way, if you are low on refrigerant then you have a leak that needs to be repaired. Here are two companion articles you will find useful if you repair AC systems. PHI Learning Pvt. However, a radiator leak can occur if one of these components goes bad. Fix: Clean condenser fins and check for dented condenser tubes. If the engine is running and your gauges are showing low side pressure too low and warm air is coming out There are several constraints that cause this state. Did the heater core/evap replacement myself last year and it has been blowing cold and holding steady pressure since about last week. If the system is continuing Note: appearance of your Comment below may be delayed: if your comment contains an image, web link, or text that looks to the software as if it might be a web link, your posting will appear after it has been approved by a moderator. Compressor turns on. Our Comment Box is provided by Countable Web Productions countable.ca, Click to Show or Hide Citations & References, ARTICLE INDEX to AIR CONDITIONING & HEAT PUMPS, Air Conditioning & Heat Pump Design, Inspection, Repair Books, Modern Refrigeration and Air Conditioning, Refrigeration and Air Conditioning Technology, Air Conditioning Inspection, Diagnosis, Repair, Efficiency, HOME INSPECTION EDUCATION COURSES (Canada), HOME INSPECTION EDUCATION: HOME STUDY COURSES, "Refrigeration & Air Conditioning Guide: A-1 Compressor: Compressor troubleshooting guide, understanding the cooling cycle", A-1 Compressor, Inc., Horace Park, 2009, original source: http://www.rpctubes.com/images/CompressorTroubleshootingGuide.pdf. WebWhat is normal automotive air conditioner pressure? Wanted to post an update, I did all this last friday night. Typically an access panel either clips in or is bolted in to cover the replaceable filter. The air inside cab is down to 50 degrees. If you missed part I, start here. Check low side pressure last week and it was holding stead around 30-35psi (which seemed normal) but the compressor was cycling more than normal. Adjust your Low Pressure control to stop before it hit 0 psi. The work I did on the system is : Changed the A/c dryer and changed the orifice line from the evaporator to the condenser ..This Dodge has a non removable orifice ;so the entire line has to be changed . Ambient Temp: 64. When running, but AC turned off, it had full pressure. The compressor will cycle at this point but engine temp is still relatively cool but after approx 10 minutes of driving the compressor clutch will not engage "Also suspect the A forum community dedicated to all jeep owners and enthusiasts. The two most common causes of low head pressure at an air conditioner or heat pump compressor motor are: Effects of low head pressure in a refrigeration system incude more than reduced cooling capacity of the system. 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