Ductless Mini-split efficiency/seer comparision quesiton

[chrispyny]

Thanks for all who dropped by to read this.

I have a question about Seer ratings for a well known brand and other lesser known or 'more economical' brands efficiency/seer comparisons.

I need a 2 zone unit. A 9k and a 24k btu. So i'm shopping on our well known on line vendors website that i have read about so much here over the past and came across 11 options per the vendors website. I have narrowed my options down to two. Either a very well known Mitsubishi unit, or a lesser known, economical model Gree. I made this decision in two parts.
1. Either i'm going to spend the extra and get a well known Mitsu unit and be happy, and then spend another $600 in linesets, covers, parts, etc.
2. Or I'm going to follow other users experiences, save myself $600 on the unit, and spend that $$ on linesets, covers, parts, etc.

So.

http://www.ecomfort.com/Gree-G2H30T09240000/p63300.html $3,021

This Gree unit (which many here seem to stand by from experience, although its certainly the 'more economical' option) seems to carry a seer rating of 21.0. However it calls for a 30 amp breaker.
Per the manual, the Gree Multi30HP230v1BO specs at a max amp draw of 13.9 amps which is a power consumption of 3,206 watts, when the outdoor temp is 95°f, and the indoor temp is 80°f. ( AHRI test standard)

Lets compare a similar Mitsubishi unit.

http://www.ecomfort.com/Mitsubishi-M2H30W09240000-B/p56946.html $3,646

This Mitsu unit carries a seer rating of 17.6, and calls for a 25 amp breaker.
Per the manual for the MXZ-3C30NA, the unit specs out at a max amp draw of 11.65 amps, which is a power consumption of 2,680 watts at AHRI testing temp standard again of 95°f outside, 80°f inside.

In summary, the Mitsu unit uses 526 less watts of power(2.28a) at AHRI testing standards, yet is rated at 3.4 seer LESS(supposedly less efficient) than the more affordable Gree model.

So what gives. Are the manufacturers playing with numbers?

Ultimately i think i willl save $$ over the longer term with the Mitsu. The 526 less watts i'll be using, will ultimately save me the $625 price difference between the two units.

Just did the math. Lets assume that i only use the unit at full power for 30 days of the summer. Lets also assume that its under full power for 12 hours a day. The online calculation explains it like this.
526 watts x 12h = 6.312 kwh.
6.312kwh per day x 30 days= 189.66 kwh in a high use month.

My power company National Grid charges $1.58 per kwh within the last few months. It varies, so... 189.36x$1.58= $299.19
This calculation is faulty as its linear. It's not possible to do a perfect calculation unless i have a summers usage with either unit to determine exactly how much i used the unit. It's rough, but helps get an idea of how long it will take me to save the difference in cost of units.

Please keep in mind, i will be using one of these units 95% of the time for cooling only. I already have NG hot water baseboard heat, and i burn wood in the wood stove all winter long. So heating is NOT a factor in these calculations.

What do you all think? Thanks !

 

[Jackfre]

I would suggest that you do the through evaluation of each system, to include heat. I've seen many people assume that a new piece of equipment won't change the way they live. I think you will find that the heat performance will lead you to use it a lot, at the very least in the shoulder season when you may not want to fire up the boiler or build a fire.

I'd go Fujitsu (I'm biased, I used to represent them in your area), Mitsu, Daikin, Gree for support reasons.

 

[OldSoldier]

You pay $1.58 per kWh?

 

[bzinsky]

$1.58 per kwh is the highest priced electric I've ever heard of

Islands in the caribbean are like 50-60 cents

 

[Fixin'Stuff]

I suspect that the OP's electricity really costs $0.158 per KWh. That changes his math quite a bit...

 

[chrispyny]

Pardon. You are all correct. It turns out it's 11.8 cents per kwh. I was looking at the chart wrong. I was looking at daily electric cost, and not kwh.

Using last months bill as an average, for 258 kwh, my bill after service, delivery, taxes etc was $30.55.
So it will take MUCH longer to recoupe the costs of the mitsu unit over the no name Gree.
Honestly i'm at a loss at this point. Does anyone care to share which they would choose if you were me please?

 

[justinjoyal]

I don't know what kind of support you have from Gree in your area, but I can tell you this:

I've sold/installed dozens of Gree units like you're showing here, all troublefree.

We've had more problems with Fujitsu units, actually.

I would not hesitate one second to purchase a Gree system like you've shown.

 

[Tehvine]

I've had my Gree 12k BTU 220v for over a year now. Works excellent - I have another on order for the bedroom currently. I went with 16 SEER, calculated electricity usage vs a 21... didn't pay. Would take something like 6-7 years to make up the cost difference and break even in my usage case. The odds of it breaking or needing major service in that timeframe caused me to just get the lower efficiency. Figure I'll just replace it if a major component fails and not be gambling that it will last long enough to pay off the difference.

Shame that I waited until a few weeks ago to order the second one, they were $760 shipped for the longest time, just jumped up to $900 now.

Also, assuming you are installing this yourself, I see that you are in Albany NY. I am in Orange County -- Security Plumbing and heating supply here was very cheap for linesets. Lineset for my unit was about $65. Next cheapest online was like $250. They have a location in Albany too: http://www.secsupply.com/albany/ Of course, you will want to cut the pre-flared ends off the lineset and use a proper flaring tool for the AC connections as well as the nuts that come with the unit. Buying the lineset from them was significantly cheaper than buying the insulation and bare copper from lowes or home depot to make my own set.

They also sell Micron gauges, manifolds, valve core tools, and the lowest cost vacuum pump oil i could source locally. They have turned into my go-to place for plumbing / heating needs when they are open.

 

[chrispyny]

Wow thanks man. May i ask where you purchased your gree unit from?

 

[theoldwizard1]

Gree is pretty new in the US. If it ever breaks, getting parts may be an issue !

 

[Tehvine]

Wow thanks man. May i ask where you purchased your gree unit from?

I bought mine from ecomfort.com since their prices include freight / lift gate service on almost all of the units.

And yes, I agree on the fact that parts may be limited. That is why I purchased the lowest SEER rated unit. Don't want to gamble on being able to find parts when/if it fails in a few years. If I wanted parts availability I would have gone with a mitsu.