Why mismatch system failure after 10 years.

[SpinnerCO]

Cool and comfortable now. 2nd opinion agreed with first tech. Turns out...

We had leak at the elbow exiting the cased coils.

What was done was...
Replaced the R-22 cased coils with TXC049 coil. Tech tried to get just the coils into our existing case, but alas it would not fit. So we had new case installed. Freeze-stat was removed as it was placed on there specifically to handle the mismatch R-22 air handler with R-410 compressor. Dirty system was dumped and evacuated to 190 microns. Dip switches were adjusted as they were not correct on the furnace. Humidifier was removed as the location (side of cased coils) was inefficient. May or may not have that moved to a different location in the fall. Tech pointed out that the sensor for the humidifier was also incorrectly wired so he doubted it worked properly anyway. Tech also STRONGLY recommended that we remove our block 6' L enclosure to our compressor as it was stressing the compressor components and sucking the life out of it.

Tech handled my million what's what thing, and why are doing that, and what is that tool, and where are you going to put that thing, and why are you measuring that, where does that go, what does that thing tell you, why did you take that off... questions patiently and respectfully. And considering he was here for about 6 hours, it was a lot of questions.

It was a hot day, 85-90. After closing all my windows, he turned on the system and started to cool down the house. After about 10 minutes we were all standing next to the compressor and he told me to go inside and upstairs and see if I noticed a difference. I scoffed quietly and said to myself... (okay dude, whatever, it's only been 10 minutes... my house needs at least an hour before it's noticeably cooler inside, especially upstairs.) But I walked into the house.. and upstairs and to my amazement and frankly disgust for 10 years of living with a system that really didn't work properly.. I had a cool house. And I have a quieter compressor.

Moral of this story... get a system that matches the needs of your house. The amount of air your duct work can handle, matched with the amount of air your system moves is crucial to a balanced system. Bigger isn't better here. There is only so much air that can move through the ducts. Just like there is only so much water you can pump through a pipe or a hose. And in the end, you make the compressor work harder and burn out more quickly.

Thanks for everyone's help, and to the tech here in Colorado who was patient enough to walk this homeowner through every step of his job.

[darctangent]

Soooooo........ I have a 4 ton AC outside. Apparently I have 3 tons of return inside the house. DH states that he had original installers out to inspect the system after he noticed freezing 10 years ago. They at that time installed the freeze-stat.

So we have a R-22 air handler coil. With a R-22 TXV that may or may not have been factory. With R-410 ac outside.

10 years no problems... now we have air handler coil freezing.

I can have a new air handler coil installed... R-410. But with 4 ton unit outside and 3 tons of return am I still going to have freezing.... still going to need a freeze-stat?

Question: Could the R-22 air handler and R410 condenser differences cause freezing? If so, then I should replace the R-22 air handler.

Question: If the cause of my freezing is actually the 4ton compressor with 3 ton of return... replacing the coil really doesn't do anything.

Question: If my "real" problem is a broken freeze-stat... that has been functioning this whole time (but masking the larger airflow problem), can I just have it replaced? Turning a blind eye to the proper fix which would be whole system overhaul which doesn't light my fire, nor keep me cool....

Tracking down a 2nd opinion guy. This is so much fun!

Where in colorado are you located?

[SpinnerCO]

Centennial DTC