Question for HyundaiTech on replacing the A/C Expansion Valve

2002 Hyundai SantFe GLS, 2.7 litre

HOW difficult is it to replace this ? Can it be done from the engine bay alone, or, does it require tearing into the dash as well ? I am a residential A/C Tech and was thinking of giving it a go. Please advise. Thanks much. David.

Reply to
ilbebauck
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alone, or, does it require tearing into the dash as well ? I am a resid ential A/C Tech and was thinking of giving it a go. Please advise. Tha nks much. David.

Presuming the parts catalog illustration is correct, the expansion valve is located externally on the firewall. You'd need to evacuate the a/c, unbol t and remove the lines from the expansion valve, and unbolt and remove the expansion valve. Of course, you'll need to vacuum and recharge when done.

The real determiners are whether you can get to the expansion valve with re lative ease and whether the fasteners cooperate.

I'm curious as to why you'd be replacing this. Failures are very rare.

Reply to
hyundaitech

H.T. , The Gauges tell the story ; unless there is a restricted liquid line filter mesh which I don't see in the line ... then I have an Expansion Valve that isn't opening .

Reply to
ilbebauck

Are you pulling a vacuum on one side with normal or high pressure on the other?

Reply to
hyundaitech

alone, or, does it require tearing into the dash as well ? I am a resid ential A/C Tech and was thinking of giving it a go. Please advise. Tha nks much. David.

When I have pulled a vacuum , its been from the low and high side and I do it for a few hours . I have a JB 3 cfm 2-stage Vaccuum Pump . The a/c wa s working fine then I noticed it cooling sporadically and finally just a li ttle . The gauge readings were lower than normal on the low side and highe r than normal on the high side as it was in the process of cooling just a l ittle (vent discharge temp was 75 f and inside of car was 95 f) . Suction line was not cool to the touch. Refrigerant charge full. Condenser was pow er washed clean. Cabin filter new . Both radiator/condenser fans turning at full speed during the diagnosis.

Reply to
ilbebauck

ay alone, or, does it require tearing into the dash as well ? I am a res idential A/C Tech and was thinking of giving it a go. Please advise. T hanks much. David.

o it for a few hours . I have a JB 3 cfm 2-stage Vaccuum Pump . The a/c was working fine then I noticed it cooling sporadically and finally just a little . The gauge readings were lower than normal on the low side and hig her than normal on the high side as it was in the process of cooling just a little (vent discharge temp was 75 f and inside of car was 95 f) . Suctio n line was not cool to the touch. Refrigerant charge full. Condenser was p ower washed clean. Cabin filter new . Both radiator/condenser fans turnin g at full speed during the diagnosis.

Do you recall the pressures?

Reply to
hyundaitech

Low side was sitting about 20 psi / high side at 275 psi @ 85 f. ambient. Pressures stayed there under fast idle of about 1500 rpms, both electric fans going. Im quite sure its the TXV . Looks like its quite easy to replace from the engine bay .

Reply to
ilbebauck

ay alone, or, does it require tearing into the dash as well ? I am a res idential A/C Tech and was thinking of giving it a go. Please advise. T hanks much. David.

ient. Pressures stayed there under fast idle of about 1500 rpms, both elec tric fans going. Im quite sure its the TXV . Looks like its quite easy to replace from the engine bay .

The pressures do seem to suggest a restriction. I've only ever replaced on e expansion valve for a similar issue, and it was on a Subaru.

Hold the high pressure line down and shake it around when you get it off. I have seen a couple cases where the desiccant comes out of the receiver dr ier and blocks the expansion valve.

Reply to
hyundaitech

alone, or, does it require tearing into the dash as well ? I am a resid ential A/C Tech and was thinking of giving it a go. Please advise. Tha nks much. David.

Ok, I shall shake the liquid line when I get it off of the txv ... and mayb e do a light suction on it with my shop vac. I strongly suspect the TXV is the culprit because before , it would provide sporadic cooling which eve ntually decreased to very little cooling. And im positive there is no moist ure or air in the system as im very careful when I purge the Gauge Manifold Lines and when Ive used the Vaccuum Pump. Anyway, im going to go ahead a nd order it in. I can let you know the outcome after its installed if you like. Thanks for all the help.

Reply to
ilbebauck

What is a "TXV?" Please explain.

I have been experiencing the same or similar symptoms in my 2000 Sonata, so would appreciate some insight.

Richard

Reply to
Richard Steinfeld

I presume Dave is using "TXV" to indicate "thermal expansion valve."

I wouldn't rush to this conclusion on your vehicle, Richard. Without the supporting pressure readings, the symptoms are much more frequently associated with insufficient refrigerant caused by a slow leak.

Reply to
hyundaitech

alone, or, does it require tearing into the dash as well ? I am a resid ential A/C Tech and was thinking of giving it a go. Please advise. Tha nks much. David.

Richard, 'TXV' means Thermostatic Expansion Valve. Like HyundaiTech sai d, TXV's are actually pretty reliable and the most common cause is a loss of regrigerant causing lack of cooling. In my case, the refrigerant level is correct and I have a completely moisture and air free internal system b eing in the A/C trade myself. If I were you, id spend the diagnostic fee on having your car a/c properly looked at ; could be something quite simpl e like finding and fixing a leak then replenishing the refrigerant lost , o r even just a dirty condenser coil causing higher than normal hi-side press ure which will inhibit good cooling . Take it in and have it diagnosed by a professional in your locale, then go from there.

Reply to
ilbebauck

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