air conditioner blowing warm air.
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I know this is probably going to upset a lot of users because in 99 percent of the states its still freezing *** cold, but in Dallas, we are seeing a heat wave for a few days and air conditioning has been used since about sunday.
the problem is that my air is coming out warm. the temperature outside is about 65 degrees, but the inside of my car is around 85-90 (i happened to have a thermometer).
the air clicks on immediately as soon as the car is turned on, but all it put out was warm air. i drove around for approximately a half hour to see if it would eventually cool down, and it the air cooled down about 10 degrees colder than what it was blowing, but still nowhere near what an airconditioner should be blowing out. at best it was blowing 80 Degree air.
anyone have any ideas what this could be aside from the obvious fact that it needs to be recharged? could this have anything to do with the fact that i just had my serpentine belt changed even though the serpentine and airconditioner arent related as far as i know. ive only had my car since novemember, i seem to remember the air working, but im not positive it ever has. what should i do?
the problem is that my air is coming out warm. the temperature outside is about 65 degrees, but the inside of my car is around 85-90 (i happened to have a thermometer).
the air clicks on immediately as soon as the car is turned on, but all it put out was warm air. i drove around for approximately a half hour to see if it would eventually cool down, and it the air cooled down about 10 degrees colder than what it was blowing, but still nowhere near what an airconditioner should be blowing out. at best it was blowing 80 Degree air.
anyone have any ideas what this could be aside from the obvious fact that it needs to be recharged? could this have anything to do with the fact that i just had my serpentine belt changed even though the serpentine and airconditioner arent related as far as i know. ive only had my car since novemember, i seem to remember the air working, but im not positive it ever has. what should i do?
#4
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Look to see if you A/C belt is tensioned. After I got my serpentine belt changed, the dealer must have knocked my A/C belt loose, because it wasn't even tight.
Since you are in Dallas, I assume you use your A/C pretty often which leads me to believe that your seals are well lubricated. Honestly a 2004 should not be low on refridgerant unless there is a fairly strong leak.
Check the belt, and if that's ok, take it your local A/C place and have them die test the system.
Since you are in Dallas, I assume you use your A/C pretty often which leads me to believe that your seals are well lubricated. Honestly a 2004 should not be low on refridgerant unless there is a fairly strong leak.
Check the belt, and if that's ok, take it your local A/C place and have them die test the system.
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e problem may not have anything to do with the compressor. The 350Z from what I have been told has certain sensors inside the cabin that read the temp inside and do funny stuff with the heat and AC. I had a similar problem with my AC and it was a cabin temp sensor that was defective. I would think it was something simple it could also be the harnes behind the HVAC controls that has gotten screwed up. I had that problem after they fixed my stereo.
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if it was a faulty cabin temp sensor wouldnt i also have problems with the heat? cuz i mean the heat comes on and gets to temp and then calms down the way its supposed to.
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The A/C system is not affected by coolant system level/abnormalities like your heat is (which utilizes a heater core).
Here is more info than you would ever need regarding how your car's A/C works:
![](http://www.familycar.com/classroom/Images/AC_Layout.jpg)
Here is more info than you would ever need regarding how your car's A/C works:
![](http://www.familycar.com/classroom/Images/AC_Layout.jpg)
COMPRESSOR
Commonly referred to as the heart of the system, the compressor is a belt driven pump that is fastened to the engine. It is responsible for compressing and transferring refrigerant gas.
The A/C system is split into two sides, a high pressure side and a low pressure side; defined as discharge and suction. Since the compressor is basically a pump, it must have an intake side and a discharge side. The intake, or suction side, draws in refrigerant gas from the outlet of the evaporator. In some cases it does this via the accumulator.
Once the refrigerant is drawn into the suction side, it is compressed and sent to the condenser, where it can then transfer the heat that is absorbed from the inside of the vehicle.
CONDENSER
This is the area in which heat dissipation occurs. The condenser, in many cases, will have much the same appearance as the radiator in you car as the two have very similar functions. The condenser is designed to radiate heat. Its location is usually in front of the radiator, but in some cases, due to aerodynamic improvements to the body of a vehicle, its location may differ. Condensers must have good air flow anytime the system is in operation. On rear wheel drive vehicles, this is usually accomplished by taking advantage of your existing engine's cooling fan. On front wheel drive vehicles, condenser air flow is supplemented with one or more electric cooling fan(s).
As hot compressed gasses are introduced into the top of the condenser, they are cooled off. As the gas cools, it condenses and exits the bottom of the condenser as a high pressure liquid.
EVAPORATOR
Located inside the vehicle, the evaporator serves as the heat absorption component. The evaporator provides several functions. Its primary duty is to remove heat from the inside of your vehicle. A secondary benefit is dehumidification. As warmer air travels through the aluminum fins of the cooler evaporator coil, the moisture contained in the air condenses on its surface. Dust and pollen passing through stick to its wet surfaces and drain off to the outside. On humid days you may have seen this as water dripping from the bottom of your vehicle. Rest assured this is perfectly normal.
The ideal temperature of the evaporator is 32° Fahrenheit or 0° Celsius. Refrigerant enters the bottom of the evaporator as a low pressure liquid. The warm air passing through the evaporator fins causes the refrigerant to boil (refrigerants have very low boiling points). As the refrigerant begins to boil, it can absorb large amounts of heat. This heat is then carried off with the refrigerant to the outside of the vehicle. Several other components work in conjunction with the evaporator. As mentioned above, the ideal temperature for an evaporator coil is 32° F. Temperature and pressure regulating devices must be used to control its temperature. While there are many variations of devices used, their main functions are the same; keeping pressure in the evaporator low and keeping the evaporator from freezing; A frozen evaporator coil will not absorb as much heat.
PRESSURE REGULATING DEVICES
Controlling the evaporator temperature can be accomplished by controlling refrigerant pressure and flow into the evaporator. Many variations of pressure regulators have been introduced since the 1940's. Listed below, are the most commonly found.
ORIFICE TUBE
The orifice tube, probably the most commonly used, can be found in most GM and Ford models. It is located in the inlet tube of the evaporator, or in the liquid line, somewhere between the outlet of the condenser and the inlet of the evaporator. This point can be found in a properly functioning system by locating the area between the outlet of the condenser and the inlet of the evaporator that suddenly makes the change from hot to cold. You should then see small dimples placed in the line that keep the orifice tube from moving. Most of the orifice tubes in use today measure approximately three inches in length and consist of a small brass tube, surrounded by plastic, and covered with a filter screen at each end. It is not uncommon for these tubes to become clogged with small debris. While inexpensive, usually between three to five dollars, the labor to replace one involves recovering the refrigerant, opening the system up, replacing the orifice tube, evacuating and then recharging. With this in mind, it might make sense to install a larger pre filter in front of the orifice tube to minimize the risk of of this problem reoccurring. Some Ford models have a permanently affixed orifice tube in the liquid line. These can be cut out and replaced with a combination filter/orifice assembly.
THERMAL EXPANSION VALVE
Another common refrigerant regulator is the thermal expansion valve, or TXV. Commonly used on import and aftermarket systems. This type of valve can sense both temperature and pressure, and is very efficient at regulating refrigerant flow to the evaporator. Several variations of this valve are commonly found. Another example of a thermal expansion valve is Chrysler's "H block" type. This type of valve is usually located at the firewall, between the evaporator inlet and outlet tubes and the liquid and suction lines. These types of valves, although efficient, have some disadvantages over orifice tube systems. Like orifice tubes these valves can become clogged with debris, but also have small moving parts that may stick and malfunction due to corrosion.
RECEIVER-DRIER
The receiver-drier is used on the high side of systems that use a thermal expansion valve. This type of metering valve requires liquid refrigerant. To ensure that the valve gets liquid refrigerant, a receiver is used. The primary function of the receiver-drier is to separate gas and liquid. The secondary purpose is to remove moisture and filter out dirt. The receiver-drier usually has a sight glass in the top. This sight glass is often used to charge the system. Under normal operating conditions, vapor bubbles should not be visible in the sight glass. The use of the sight glass to charge the system is not recommended in R-134a systems as cloudiness and oil that has separated from the refrigerant can be mistaken for bubbles. This type of mistake can lead to a dangerous overcharged condition. There are variations of receiver-driers and several different desiccant materials are in use. Some of the moisture removing desiccants found within are not compatible with R-134a. The desiccant type is usually identified on a sticker that is affixed to the receiver-drier. Newer receiver-driers use desiccant type XH-7 and are compatible with both R-12 and R-134a refrigerants.
ACCUMULATOR
Accumulators are used on systems that accommodate an orifice tube to meter refrigerants into the evaporator. It is connected directly to the evaporator outlet and stores excess liquid refrigerant. Introduction of liquid refrigerant into a compressor can do serious damage. Compressors are designed to compress gas not liquid. The chief role of the accumulator is to isolate the compressor from any damaging liquid refrigerant. Accumulators, like receiver-driers, also remove debris and moisture from a system. It is a good idea to replace the accumulator each time the system is opened up for major repair and anytime moisture and/or debris is of concern. Moisture is enemy number one for your A/C system. Moisture in a system mixes with refrigerant and forms a corrosive acid. When in doubt, it may be to your advantage to change the Accumulator or receiver in your system. While this may be a temporary discomfort for your wallet, it is of long term benefit to your air conditioning system.
Commonly referred to as the heart of the system, the compressor is a belt driven pump that is fastened to the engine. It is responsible for compressing and transferring refrigerant gas.
The A/C system is split into two sides, a high pressure side and a low pressure side; defined as discharge and suction. Since the compressor is basically a pump, it must have an intake side and a discharge side. The intake, or suction side, draws in refrigerant gas from the outlet of the evaporator. In some cases it does this via the accumulator.
Once the refrigerant is drawn into the suction side, it is compressed and sent to the condenser, where it can then transfer the heat that is absorbed from the inside of the vehicle.
CONDENSER
This is the area in which heat dissipation occurs. The condenser, in many cases, will have much the same appearance as the radiator in you car as the two have very similar functions. The condenser is designed to radiate heat. Its location is usually in front of the radiator, but in some cases, due to aerodynamic improvements to the body of a vehicle, its location may differ. Condensers must have good air flow anytime the system is in operation. On rear wheel drive vehicles, this is usually accomplished by taking advantage of your existing engine's cooling fan. On front wheel drive vehicles, condenser air flow is supplemented with one or more electric cooling fan(s).
As hot compressed gasses are introduced into the top of the condenser, they are cooled off. As the gas cools, it condenses and exits the bottom of the condenser as a high pressure liquid.
EVAPORATOR
Located inside the vehicle, the evaporator serves as the heat absorption component. The evaporator provides several functions. Its primary duty is to remove heat from the inside of your vehicle. A secondary benefit is dehumidification. As warmer air travels through the aluminum fins of the cooler evaporator coil, the moisture contained in the air condenses on its surface. Dust and pollen passing through stick to its wet surfaces and drain off to the outside. On humid days you may have seen this as water dripping from the bottom of your vehicle. Rest assured this is perfectly normal.
The ideal temperature of the evaporator is 32° Fahrenheit or 0° Celsius. Refrigerant enters the bottom of the evaporator as a low pressure liquid. The warm air passing through the evaporator fins causes the refrigerant to boil (refrigerants have very low boiling points). As the refrigerant begins to boil, it can absorb large amounts of heat. This heat is then carried off with the refrigerant to the outside of the vehicle. Several other components work in conjunction with the evaporator. As mentioned above, the ideal temperature for an evaporator coil is 32° F. Temperature and pressure regulating devices must be used to control its temperature. While there are many variations of devices used, their main functions are the same; keeping pressure in the evaporator low and keeping the evaporator from freezing; A frozen evaporator coil will not absorb as much heat.
PRESSURE REGULATING DEVICES
Controlling the evaporator temperature can be accomplished by controlling refrigerant pressure and flow into the evaporator. Many variations of pressure regulators have been introduced since the 1940's. Listed below, are the most commonly found.
ORIFICE TUBE
The orifice tube, probably the most commonly used, can be found in most GM and Ford models. It is located in the inlet tube of the evaporator, or in the liquid line, somewhere between the outlet of the condenser and the inlet of the evaporator. This point can be found in a properly functioning system by locating the area between the outlet of the condenser and the inlet of the evaporator that suddenly makes the change from hot to cold. You should then see small dimples placed in the line that keep the orifice tube from moving. Most of the orifice tubes in use today measure approximately three inches in length and consist of a small brass tube, surrounded by plastic, and covered with a filter screen at each end. It is not uncommon for these tubes to become clogged with small debris. While inexpensive, usually between three to five dollars, the labor to replace one involves recovering the refrigerant, opening the system up, replacing the orifice tube, evacuating and then recharging. With this in mind, it might make sense to install a larger pre filter in front of the orifice tube to minimize the risk of of this problem reoccurring. Some Ford models have a permanently affixed orifice tube in the liquid line. These can be cut out and replaced with a combination filter/orifice assembly.
THERMAL EXPANSION VALVE
Another common refrigerant regulator is the thermal expansion valve, or TXV. Commonly used on import and aftermarket systems. This type of valve can sense both temperature and pressure, and is very efficient at regulating refrigerant flow to the evaporator. Several variations of this valve are commonly found. Another example of a thermal expansion valve is Chrysler's "H block" type. This type of valve is usually located at the firewall, between the evaporator inlet and outlet tubes and the liquid and suction lines. These types of valves, although efficient, have some disadvantages over orifice tube systems. Like orifice tubes these valves can become clogged with debris, but also have small moving parts that may stick and malfunction due to corrosion.
RECEIVER-DRIER
The receiver-drier is used on the high side of systems that use a thermal expansion valve. This type of metering valve requires liquid refrigerant. To ensure that the valve gets liquid refrigerant, a receiver is used. The primary function of the receiver-drier is to separate gas and liquid. The secondary purpose is to remove moisture and filter out dirt. The receiver-drier usually has a sight glass in the top. This sight glass is often used to charge the system. Under normal operating conditions, vapor bubbles should not be visible in the sight glass. The use of the sight glass to charge the system is not recommended in R-134a systems as cloudiness and oil that has separated from the refrigerant can be mistaken for bubbles. This type of mistake can lead to a dangerous overcharged condition. There are variations of receiver-driers and several different desiccant materials are in use. Some of the moisture removing desiccants found within are not compatible with R-134a. The desiccant type is usually identified on a sticker that is affixed to the receiver-drier. Newer receiver-driers use desiccant type XH-7 and are compatible with both R-12 and R-134a refrigerants.
ACCUMULATOR
Accumulators are used on systems that accommodate an orifice tube to meter refrigerants into the evaporator. It is connected directly to the evaporator outlet and stores excess liquid refrigerant. Introduction of liquid refrigerant into a compressor can do serious damage. Compressors are designed to compress gas not liquid. The chief role of the accumulator is to isolate the compressor from any damaging liquid refrigerant. Accumulators, like receiver-driers, also remove debris and moisture from a system. It is a good idea to replace the accumulator each time the system is opened up for major repair and anytime moisture and/or debris is of concern. Moisture is enemy number one for your A/C system. Moisture in a system mixes with refrigerant and forms a corrosive acid. When in doubt, it may be to your advantage to change the Accumulator or receiver in your system. While this may be a temporary discomfort for your wallet, it is of long term benefit to your air conditioning system.
#16
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Originally Posted by DJMatrix1067
I know this is probably going to upset a lot of users because in 99 percent of the states its still freezing *** cold, but in Dallas, we are seeing a heat wave for a few days and air conditioning has been used since about sunday.
the problem is that my air is coming out warm. the temperature outside is about 65 degrees, but the inside of my car is around 85-90 (i happened to have a thermometer).
the air clicks on immediately as soon as the car is turned on, but all it put out was warm air. i drove around for approximately a half hour to see if it would eventually cool down, and it the air cooled down about 10 degrees colder than what it was blowing, but still nowhere near what an airconditioner should be blowing out. at best it was blowing 80 Degree air.
anyone have any ideas what this could be aside from the obvious fact that it needs to be recharged? could this have anything to do with the fact that i just had my serpentine belt changed even though the serpentine and airconditioner arent related as far as i know. ive only had my car since novemember, i seem to remember the air working, but im not positive it ever has. what should i do?
the problem is that my air is coming out warm. the temperature outside is about 65 degrees, but the inside of my car is around 85-90 (i happened to have a thermometer).
the air clicks on immediately as soon as the car is turned on, but all it put out was warm air. i drove around for approximately a half hour to see if it would eventually cool down, and it the air cooled down about 10 degrees colder than what it was blowing, but still nowhere near what an airconditioner should be blowing out. at best it was blowing 80 Degree air.
anyone have any ideas what this could be aside from the obvious fact that it needs to be recharged? could this have anything to do with the fact that i just had my serpentine belt changed even though the serpentine and airconditioner arent related as far as i know. ive only had my car since novemember, i seem to remember the air working, but im not positive it ever has. what should i do?
#17
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I also have a problem with my a/c. Sometimes when set to auto it will stop blowing out cold air, but when i go to manual it will start getting cooler. Not sure if this is related, but when it does start blowing out hot air I have noticed the temp guage going up to 105+ degrees. This problem remains intermittent.
#18
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Update on my problem...
Today before I left to work I let my car idle in the garage for about 10 mins and the a/c never got cold. I tried switching from Auto to Manual mode and switching the a/c button on and off and the air stayed warm. I had to get going to work and it seems once I got to 4th gear the air started to get cool. While waiting at a stop light it once again became warmer and cooled again after getting to 3rd or 4th gear.
This problem also never seems to happen when I first start driving around in the morning so it seems to happen only when the engine is already hot.
I had this problem a couple of times in the passed two years and took it to the dealer and they could not find anything wrong with it. Now that I'm passed the warranty period, it is happening almost everyday now.
Today before I left to work I let my car idle in the garage for about 10 mins and the a/c never got cold. I tried switching from Auto to Manual mode and switching the a/c button on and off and the air stayed warm. I had to get going to work and it seems once I got to 4th gear the air started to get cool. While waiting at a stop light it once again became warmer and cooled again after getting to 3rd or 4th gear.
This problem also never seems to happen when I first start driving around in the morning so it seems to happen only when the engine is already hot.
I had this problem a couple of times in the passed two years and took it to the dealer and they could not find anything wrong with it. Now that I'm passed the warranty period, it is happening almost everyday now.
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bummer you're out of warranty. did the dealership ever evacuate the refrigerant, check for leaks, then recharge it with the proper amount? that's the first thing they should have done. call the service manager and look up your service records.
at idle, the engine rpm (the AC compressor runs off the engine) are low so the compressor is not moving much refrigerant and thus it's hard for it to cool the air.
it sounds like you're low on refrigerant because at speed you're getting cold air, when you slow down, your ac goes to crap.
2 things help AC performance, air flow over the condenser and AC compressor rpm. so going down the road at 45 mph, there's airflow and your engine rpm is at 2-3000 rpm.
if you take it to a shop/dealer they have to check the high and low pressures. they'll probably say you're low on charge, evacuate the system, check for leaks, then recharge it with the proper amount. but make sure they check for leaks... either with a R134 sniffer or by checking if it holds vacuum for 30 minutes. because if they don't, you'll just have the same problem 6 months later.
at idle, the engine rpm (the AC compressor runs off the engine) are low so the compressor is not moving much refrigerant and thus it's hard for it to cool the air.
it sounds like you're low on refrigerant because at speed you're getting cold air, when you slow down, your ac goes to crap.
2 things help AC performance, air flow over the condenser and AC compressor rpm. so going down the road at 45 mph, there's airflow and your engine rpm is at 2-3000 rpm.
if you take it to a shop/dealer they have to check the high and low pressures. they'll probably say you're low on charge, evacuate the system, check for leaks, then recharge it with the proper amount. but make sure they check for leaks... either with a R134 sniffer or by checking if it holds vacuum for 30 minutes. because if they don't, you'll just have the same problem 6 months later.
#20
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You need to find out if the A/C clutch is engaging. The a/c compressor has a electrical clutch that turns on and off, start the car and look at the a/c compressor then have someone turn the a/c system. If the clutch fails to energize you won't see anything if it does you will see it and hear it start turning.
If it fails to turn it could be a few different things, first check the relay. If the relay has failed it won't engage. If the relay is good but it still fails to run you can check a few other things. First, the a/c system has a switch that if it senses a low pressure such as would exist if the refrigerant charge was lost will prevent the compressor from running so as to not damage it. You can just jumper the switch to test it but it's best to get a gage to check system pressure, system pressure not running should be the same on the high and low side, somewhere above 70 PSI. If the pressure is not high enough or at 0 you have a leak, have it fixed and recharged. If the pressure is good but the compressor cycles on and off it's short on charge, find the leak fix it and add refrigerant. Most leaks are at the compressor shaft seal. Any leak will be indicated by an oily area at a connection, trace over the piping and look at connections. You can buy a small charge with a dye to help find leaks.
If the compressor just won't run it's probably the relay.
My other Nissans with a/c problems have been leaks at the drier connection at the condenser, a pinched oring. An easy fix but requires evacuating the system and recharging.
The cabin sensor only works when the system is set to run automatically, when in manual it makes on difference.
Hope this helps...
If it fails to turn it could be a few different things, first check the relay. If the relay has failed it won't engage. If the relay is good but it still fails to run you can check a few other things. First, the a/c system has a switch that if it senses a low pressure such as would exist if the refrigerant charge was lost will prevent the compressor from running so as to not damage it. You can just jumper the switch to test it but it's best to get a gage to check system pressure, system pressure not running should be the same on the high and low side, somewhere above 70 PSI. If the pressure is not high enough or at 0 you have a leak, have it fixed and recharged. If the pressure is good but the compressor cycles on and off it's short on charge, find the leak fix it and add refrigerant. Most leaks are at the compressor shaft seal. Any leak will be indicated by an oily area at a connection, trace over the piping and look at connections. You can buy a small charge with a dye to help find leaks.
If the compressor just won't run it's probably the relay.
My other Nissans with a/c problems have been leaks at the drier connection at the condenser, a pinched oring. An easy fix but requires evacuating the system and recharging.
The cabin sensor only works when the system is set to run automatically, when in manual it makes on difference.
Hope this helps...
Last edited by fklentz; 05-22-2007 at 11:11 AM.