Higher SEER Rating

[AlwaysLearning]

I have to replace an outside unit with a new one and being as 22 units are running out I had to get a 14 SEER to replace a 10 or 11. Do I have to install a TXV or will it function properly without it. I spoke to someone that swore he has put 13 SEER against 10 without problems but I've always used a TXV.

[cdub]

It will still function properly as long as you dont have and r-22 indoor system and putting a 410a condenser on it. The metering device will not work with the different refrigerant. but to answer the question you should be fine without installing txv, may hurt eff. a little but not a major loss..... hope that helps

[momo]

I assume you are discussing centralized house duct units. Silly question, but doesn't the SEER (efficiency) rating take into account the whole system for approval? In any case all the standard issues of oils, pipe thickness and size would come into play as well as the evaporator design and the constrictor be it TXV or capillaries.

[cdub]

In the case of pipe thickness i have never heard that one before, I have installed quite a few and never ran into that issue, with higher seer system (complete new high seer systems) i have had to install a sound dampner on the line set because of a gushing sound the refrigerant was making on a lennox 21 seer. On the oil issue the system can always be cleaned out with dry nitrogen and then pull a deep vac. and your good to go. Like i said it is not always ideal to mix EER or SEER rated systems but it can be done.