Icing on the pipes coming from the radiator to the evaporator
It is a 2000 ford futura . The ac starts and cools a bit at low speeds , the moment the revs go up. cooling reduces and stops. When i popped the hood and started it, after a bit i saw ice forming on the pipes. and till it forms the cooling is there a bit. what should i do?
- If you need clarification, ask it in the comment box above.
- Better answers use proper spelling and grammar.
- Provide details, support with references or personal experience.
Tell us some more! Your answer needs to include more details to help people.You can't post answers that contain an email address.Please enter a valid email address.The email address entered is already associated to an account.Login to postPlease use English characters only.
Tip: The max point reward for answering a question is 15.
I think you have a similar problem to mine. At highway speeds is when it happens. And it is not blazing hot? Right?
Your evaporator is freezing up - as this happens the ice surrounding it prevents the flow of air over the evaporator coils and the result is warm air coming out of the registers. If I turn off the AC for about ten minutes and let unit melt the cold air comes back. This does not occur in stop and go driving.
I combat it by either running the fan at a higher than normal setting to increase air flow over the evaporator and then turning off when it gets too cold, OR using the air control to allow warmer outside air to enter into unit at highway speeds to prevent freezing up.
Newer cars have more sophisticated sensors and controls to prevent this but some older vehicles are subject to this anomaly.
Since it works fine under normal conditions I have not messed around with the freon level in system. If you release a tad of refrigerant the low pressure switch will shut off the compressor sooner and help minimize ice buildup. Good luck.
I am concerned that what you have been told may not be exactly true. If the pipe to the inside of the car from the ac compressor is frosting up ( water condensation) then it has a low pressure area which indicates that the gas is getting through the evaporator ( bit inside the car). If the evaporator was blocked then the low pressure switch would switch off the ac compressor (low gas/no gas)
because the gas could not get past the blockage then the high pressure switch would stop the compressor because of high head pressures which can damage the compressor.
The most logical thing is that the TX valve is partially blocked or the thermostat setting is wrong.preventing sufficient gas flow into the evaporator to cool the car.
If you car has a climate control system then that unit may need checking. Best have an accredited ac specialist shop check the system
And to answer you question as to possibility of flushing or cleaning or washing out the evaporator. this is not a possibility as there can be no moisture what ever inside an ac system. However you can check if the cooling fins on the evaporator are blocked with an oily type dust then you can use an ac fin cleaner . This will allow the air to pass through the evaporator fins and help boil off the gas from the TX valve.
Most likely low on refridgerant. ports are difficult to access .In front of passenger front wheel the accumulator is located. low pressure port is on top of it. Try and add a pound of 134a and see if it cools more efficiently. evaporators are common source of leak on these fine machines.
Replace the blower motor resister,this is the speeds for the blower motor,it is located very near the blower motor,and is mounted on the blower box,and it actually goes inside the box,to keep it cool.The reason for it`s failure is the blower motor,even though the blower motor sounds,and runs good,it is drawing too many amps.If this was at all helpful,please rate,thank you.
Feel of the large ac line going into the firewall,and see if it is cool,or cold,also,the condenser could be restricting flow threw it,on the inside,we really need gauge readings for low side,and high side to diagnose the problem.
if the AC isnt cooling on idle then the fan isnt coming on ,so gas isnt cooling in the rad in front of the car ,now as for the pulling away bit i wiould disconnect the servo vacumn feed pipe and block the end of the pipe and try that in case the diaphragm is letting in air causing the idle to speed up
I dont belived having bigger radiator make your ac unit run better although radiator has nothing to do with ac beside colling your engine. If that was an issue to all cases, i think GM would have recall all of their envoy due to cooling issue, that's not so. If the car has been running fine since it was band new and now it started to have this cooling problems, I dont understand how can one come up with and idea that the radiator is too small, that dont make sense to me. Your eveporator sit in front of your radiator it may not have good flow of air movement to cool down the hot gases in the evaporator, maybe fan clutch is not working properly keeping the fan run at constant speed. The unit mabe also low on feon and not having enough feon in the systems causing your systems not to run properly. Low pressure or low feon will cause the unit also to run poorly and will caused the pressure switch to cut compressor on and off more frequent. Have the pressure tested and filled if need first. being 2003, if with high miles; its it good time to also have your thermostat replace if you never have it done. Hope that help some
this is covered by your warranty for 36/36. The sensor is usually on the evaporator inside the plenum case under the dash. If the eavp drops below 32 degrees F, then ice starts to accumulate on the fins of the evaporator, and eventualy blocks the flow of air through it. You will hear the blower running, but no air coming out.
To reduce liklihood of icing, always put a/c in "recirc" mode. This recirculates the already cooled and dehumidified air back through the a/c system, therefore reducing humid air icing.
Note: never use recirc in winter because you will fog up the windows.