Heater Core & Evaporator Replacement

[arveetek]

Here's how I spent my week off work during Christmas break: replacing the heater core and evaporator on my 1995 Tahoe 2 Door Tahoe!

Whew, what a job.

I had an A/C refrigerant leak I couldn't pin down, and I also had not been happy with the air flow out of my dash vents for quite some time (always felt like there should have have been a lot more air movement coming out the vents). I decided after 419K miles, it was time to replace the original heater core, evaporator, and condenser (A/C compressor is fairly new).

I removed the entire dash assembly, and then the HVAC box:


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HVAC box removed:


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The original evaporator was packed full of nearly 30 years' worth of dirt and debris:


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And upon disassembling the HVAC box, I discovered that all three main blend/mode doors were in terrible shape; most of the rubber sealing flaps were completely gone:


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Here's a comparison of one of the old doors against the new door. You can clearly see how the new door has a rubber flap all the way around that the old door no longer has:


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New heater core and condenser (forgot to grab a pic of the new evaporator):


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New condenser going in:

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I also replaced the hard line going from the evaporator to the condenser, and of course a new drier.

I also took the time to replace all three electric actuators that open and close all the blend/mode doors.

While I wasn't looking forward to this job, all in all, it really wasn't all that bad. I took my time and was not in a hurry, so I didn't feel stressed about how long my rig would be off the road. I started the day after Christmas, and finished up this past Saturday after New Year's; and that included taking 3 days off for a mini-vacation with my wife!

I still need to vacuum and recharge the A/C system, but everything is else is back together and working properly.

With a new, clean evaporator and new blend/mode doors, there is much improvement in the amount of air moving through the dash vents.

Casey

[spongebob]

WOW..hope that cures the "leak", from the looks of the coils I can see why you didn't have all the air flow..

[56pan]

I did this same job on my '93 C2500 6.5 a few years ago. I didn't have the luxury of plenty of time. It was_the_job_from_Hell. If I ever had it to do again, I'd finally sell that old truck. My best advice, take plenty of pictures while you're disassembling things.

[arveetek]

....My best advice, take plenty of pictures while you're disassembling things.

Indeed! I forgot to take any pictures of the blend/mode door actuator linkages. I disassembled the whole HVAC box and then ordered the replacement doors. It was a few days before I got back to it, and I couldn't remember how all the linkages went together. Thankfully I found a picture on the good old Google and was able to get it back together.

Casey

[More Power]

Great job Casey! Thank you for showing us how to do it.
Jim