Cased coils started frosting over during the past month so we had tech come out to inspect. The following system components were installed in April of 2002.
Trane XL13I Model TTX3048A1000A
Trane UV80 2 Stage VS FUI UD100R9V5J
EZ Conv CDS HP/AC coil TXCO54S3HPCO R22
Trane Programmable Thermostat
Alco TXV Valve C860272-P07
Tri level home with apx 2500 sq feet. We have never had any problems with the system until now.
We had a tech come out for inspection and he states that the outdoor unit, which is R-410, is incompatible with the interior R-22. After lots of discussion about what that means, how inept the prior install company was, and how we have been sucking the life out of the X13I..... we are finally left with recommendation that is high in cost.
My question is.... why would a company mismatch the system. Was the R-22 cheaper to install?
Why has the system worked for 10 years and we only now have a problem?
Do we have to replace the interior AC coil unit with a R-410 compatible unit?
Could it simply be a faulty TXV? Can we replace it if it has failed, and keep the mismatched system?
From what I understand, R-410 is running through the R-22 lines. Is this a just a non-optimal situation or is it a dangerous situation?
I'm not looking for absolute cheapest way out of this hole.... just looking for a reasonable solution.