Long-term Reliability of Mini-split vs. Standard-split System
Breakerbox | Posted in Energy Efficiency and Durability on
Which is more reliable – or are they about the same?
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I do not think there can be a correct answer to your question just too many variables.
The biggest is the quality of the install. A bad install will quickly destroy the best equipment.
Your question is like are pickup truck more reliable than SUV? So many brands driven by different drivers over different roads.
With inverter mini-splits, you have more electronics to fail. On the other, you have fewer and gentler starts. But no idea what the net result is.
Traditional Split Systems are becoming increasingly complex by the year also though. It comes down to efficiency be complexity in a lot of cases. A 13 seer traditional split doesn’t have many moving pieces, but it’s also 13 seer haha.
Let me put it this way, if I look at 1000 systems installed at 1000 different sites, all with the similar efficiency, which would I pay the most for maintenance over 15 years. Assume as close as possible SEER and EER ratings.
> Assume as close as possible SEER and EER ratings.
The problem with this is that to get efficiency close to a good minisplit, you basically end up with a variable speed, modulating, communicating system like... a minisplit!
With a well installed system, your maintenance costs should be next to nothing unless something breaks. With a 'standard' split system, pay extra attention to the return filtering to ensure the [presumably hard to access] fan coil stays clean.
Bottom line: if you want high efficiency, there are more components and more to go wrong. But I suspect most would agree that that complexity is worth the great efficiency gains between conventional systems and modulating systems.
It's hard to say about the reliability, but I do feel like the occasionally necessary cleaning of high wall units is a bit a consumer hostile, with the almost destructive disassembly requirement.
The floor mount and ducted units don't really seem suffer from this flaw though.
Assuming end of life failure of the outdoor unit, is the indoor unit always replaced as well?
Generally the end of life failure is one or more leaks that are difficult to locate or repair with no certainty of what all parts are leaking or about to leak.
At that point the system is hopefully several years old. Since no one can guarantee that the several year old parts of the system will not fail tomorrow most installers want to replace it all so they can stand behind their work.
Also the new outdoor unit will not have been designed, rated and or tested to operate with a several year old indoor parts. Often they will work but the question is how well and efficient this random combination happens to be. It not likely to be better than the new compo engineered to work together