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I was just wondering, on our car, do we need to remove the evaporator in order to replace the expansion valve?

I looked in the manual and it doesnt really explain it, but from just looking at it, it looks like you have to remove the whole evap core/ heater core assembly in order to gain access to the expansion valve.

If anyone knows, let me know.

 
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dont we have a accumulator/orifice tube setup?? let me run down to my car and check

 
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oh, one more thing, whats the problem with your a/c?

 
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No we have a reciever/drier and expansion valve setup.

And nothing is wrong with my AC, I was just curious.

 
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^^^your right, good call. from the looks of it, you may be able to take out the expansion valve without pulling out the evaporator. your just gonna have to take out the plastic surrounding it. never done it before so im not 100 percent sure.

 
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I am not sure either, I looked at the liquid line from the reciever drier to the TXV and dont see it at the bulkhead where it goes into the evaporator. I am assuming it has to be removed.

 
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well, a receiver drier setup goes like this

a/c compressor--->condensor--->TXV--->evaporator--->receiver drier--->back to a/c compressor

i havent checked out my engine bay yet, so ill let you know as soon as i do. im just speculating right now.

 
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actually it goes compressor, condensor, reciever/drier, TXV, evaporator, back to compressor.

You might be thinking of the FOT system where the accumulator is after the evaporator.

When looking in the manaul they have a pic of the system backwards, and the TXV is before the bulkhead, but when looking I just see the liquid line going in the bulkhead and the suction line coming out.

 
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if the drier is after the condenser, then it has TXV

 
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yall guys didnt make a clear statement on which component the civic have, the orifice or expansion valve (TXV).

so which one is it?

 
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if the drier is on the high side its an TXV, if its on the low side, its a FOT type. We have a TXV system

 
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sounds like you know a lot about refrigeration.

just curious, why would the component(drier) locate at a diff location in the cycle when a certain metering device is use?

 
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well, a receiver drier is made to withstand high pressure, up to 200 psi, at the same time its got to remove moisture from the refrigerant at that level. while an accumulator only deals with removing moisture at a low psi level which is why its located after the evaporator.

 
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A drier goes after the condensor on a TXV system. With a FOT system, you have no drier, but an accumulator after the evaporator.

FOT system:

Compressor, condensor, FOT, evaporator, accumulator, back to condensor.

TXV system:

Compressor, condensor, Reciever/drier, TXV, evaporator, back to compressor.

Both are used to basically used to filter the refrigerant, but an accumulator makes sure only vapor goes back to the compressor, not any liquid.

 
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Going by our Alldata here at work, you must remove the evaporator core to remove the expansion valve. Let me know if you need more info.

 
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whats moisture in refrigeration sense?
that didnt still give me any answer.

i know the orifice give a constant volume to the evaporator coil and the TXV do not give a constant volume to the evap coil, but rather changes vol dependin on outside condition.

 
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you said back to condersor on the OT system, but i know u meant compressor.
both a receiver drier and a accumulator remove moisture from the refrigerant,act as a reservoir for excess refrigerant and compressor oil, they both have dessicant in them so i just referred both as a drier. but i know its called a accumulator in a OT system. by the way, theres 2 types of orifice tubes, fixed and variable.

 
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moisture as in the moisture from water which could cause rust inside the lines, debris from them and even could freeze up the ac lines as well

 
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oh. from liquid state or from water? if its water, how does it get build up?

maybe tidious question but tryin to learn the detail of it.

still clueless about the drier and its location.

 
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dont understand your first question. debris can form from rusted lines, dirt coming through the service ports, and even using the wrong type of oil which can create a foreign substance when mixed with the refrigerant

 
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^^^and about the drier, if its a Orifice tube system, its located in the low pressure line in between the evaporator and the compressor. Just look for the service port with a blue cap that has the letter L on it, its also the fatter of the two lines. If its a TXV system, the drier is located on the High side right in between the condensor and the thermal expansion valve which leads to the evaporator. The high side has either a black or red cap on the service port with the letter H on it. it is the skinnier tube

 
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^^^ill draw a diagram later and post it for u to see

 
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and


any questions just ask

 
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"from liquid state or from water?"

you stated water, how does water comes into the cyle when only refrigerant exist? if theres water exist, how does it get there?

thats the first and sec which i find no answer for. seems dumb to bother you but i like to know every aspect of it.

 
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water can come in for example on a hot day, when the pressur change occurs at the ot or the txv, it creates moisture. theres always gonna be some air in your system, and air contains water molecules

 
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okay, i see the drier is at two diff location w/ the metering device varies.

so why the drier on the TXV b4 the evap and why the drier on the orifice after the evap? that was the whole question about the drier.

 
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gotcha

 
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I cant remember correctly, but it has to do with the metering devices. I will check it out, I cant remember it all though.

 
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i believe its just the way they're designed, but ill double check for you.

 
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its obviously thats just the way they designed it. whats the thermodynamic behind it?