Looking at Split systems

The Steam Whisperer (Formerly Boilerpro)

I am looking at ductless split systems for use in my church and have been talking to my cooling tech.  What we are looking for is a simple, high capacity, high EER non-invertor type unit, that may also provide heating.  We will be using wall mount indoor units.   It seems the EER ratings on most new equipment are pretty dismal, typically below 10, which is worse than a decent window unit.  We want the high EER, not SEER, because the unit will essentially be running at full capacity or off (since it will be technically very undersized), so the EER rating really matters for energy cost.  In addition the building has very limited electrical capacity.  We will be working to upgrade the lighting efficiency to free up power for the air conditioning and to cut the cooling load. Non-invertor units also should be easier and cheaper to maintain due to the simplicity.  Something with wall mount units capable of a minimum of 3 tons and are quiet are needed.

If we do go to an invertor type unit it looks like the Mitsu City Multi is the best bet, with EER ratings around 15, allowing use to run 6 tons on only 12.2 amps(230v), with COP's near 4 for heating.



Your suggestions would be appreciated

NYplumber

SHR

Since this is a place where many will gather, two things to keep in mind. Sensible heat ratio and air changes per hour. Keeping the temperature cool is only part of the equation.

The Steam Whisperer (Formerly Boilerpro)

Ventilation

With the currently low attendance, the vast space, short occupancy time and high air leakage rates, ventilation is unlikely a problem at this time.  When attendance begins to increase, ERVS will probably need to be looked at.

Jack

I don't think

You are going to find a non-inverter unit in these ranges. All of the technology and inventory has been invested in inverters as they just do a better job. What kind of tonnage are you looking for and what do you think your available power supply will be? Also, I would not say that a non inverter unit is necessarily easier to service. Installed correctly the better brands of inverters are really reliable.



Also while the city multi is a great system you might be better off looking a a series of 36kbtu individual units. Bring them on as you need them. I'd be interested in the cost comparison of that type system.



Also, for heating supplement with the mini-split I look at the Rinnai ES-38. At this point consider it for load sharing on the heat side. It is a good combination.