# MrCool mini-split P4 error - Swap only outdoor condenser unit?



## John_MrCool (4 mo ago)

My MrCool 12K minisplit had a P4 error. The indoor unit would work normally but the outdoor unit wouldn't run.

I bought the exact same MrCool system. The new outdoor unit has the same model number as the old one (A-12-HP-C-230B). It occurred to me that I could simply rehook up the lines, pull a vacuum, and get the system back online without replacing the rest of it. Given that the system displayed a P4 error, that the indoor unit would operate normally, while the outdoor unit would not run, would there be a good chance that the outdoor unit had failed and I could simply hook up the lines from the existing system to the new outdoor unit and just pull a vacuum and be done?

Thanks in advance for your advice!


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