Mini Split A/C Power Consumption?

[Ozark Tinkering]

I am looking at replacing my (very) old central a/c package unit this year and the mini split units seem a very attractive alternative at this point and I believe I'll save quite a bit on my power usage since I won't be cooling or heating areas I'm not using. I'm thinking three 9k btu units will probably be adequate for my needs. My question is, has anyone here ever put a watt hour meter on a 9k or 12k btu unit to see how much power is required on an hourly basis? I need to factor that into my calculations when I size my battery bank initially, so it will carry me through until generation begins again each morning.
Thanks.

 

[BobR]

I don't have one yet but I am getting ready to get a 9000 BTU unit soon for my work shop. It will be a Blueridge BM09Y18; 18 seer. cost $699 including shipping.

When I get it I will be measuring energy use as I plan on using the same size unit for a boat instalation.

 

[timselectric]

I will be gradually be replacing my new (2.5 years old) 3 ton system, with multiple mini-split systems.

 

[brandonboosted]

I went with the cooper and hunter 9k 22 seer 120v been using it for heat all winter and my 13000kwh batteries run it all night with 30-40% left depending on how cold it is. Most it pulls is 1000w but that’s usually only for a little bit unless really cold then drops to 300-700w ish.

 

[Ampster]

My question is, has anyone here ever put a watt hour meter on a 9k or 12k btu unit to see how much power is required on an hourly basis?

I have recently installed a three head 24k LG unit but have only run two of the heads recently. A lot depends on the ambient temperature and the size of the rooms. One of the heads heats a bedroom that is 300 Sg ft and the other heats a dining area that is open to about 600 Sg ft of living area including a kitchen. The average daily consumption has been between 4-6 kWh per day. We have had mild weather and the compressor only runs hard to take the chill out of the mornings and lightly at night. Our thermostat settings vary between 65 and 70 degrees and the home is well insulated so it does not run much during the day. This may seem like a lot of detail but it will vary a lot depending on your home.

 

[schmism]

This may seem like a lot of detail but it will vary a lot depending on your home.

I think OP asked his question specifically "how much do they consume per hr" meaning if its on and running what does it consume. Everyone can then calculate how much power they need based on their location/temp/structure etc. But the base line of if its on and running then its consumeing XXXX should be the datapoint we are looking for.

 

[Ozark Tinkering]

I went with the cooper and hunter 9k 22 seer 120v been using it for heat all winter and my 13000kwh batteries run it all night with 30-40% left depending on how cold it is. Most it pulls is 1000w but that’s usually only for a little bit unless really cold then drops to 300-700w ish.

Thanks! That's the sort of info I'm looking for. The space I'm looking at using these 9k mini splits is well insulated and once temp is achieved I don't expect them to cycle very much. So your single 9k unit uses somewhere around 9kWh per night if you figure having 30% remaining charge on your system come morning sun.

I have recently installed a three head 24k LG unit but have only run two of the heads recently. A lot depends on the ambient temperature and the size of the rooms. One of the heads heads a bedroom that is 300 Sg ft and the other heats a dining area that is open to about 600 Sg ft of living area including a kitchen. The average daily consumption has been between 4-6 kWh per day. We have had mild weather and the compressor only runs hard to take the chill out of the mornings and lightly at night. Our thermostat settings vary between 65 and 70 degrees and the home is well insulated so it does not run much during the day. This may seem like a lot of detail but it will vary a lot depending on your home.

Thanks!
My rooms are pretty small and I'm going for the highest seer rating I can find. Right now I'm looking at the MrCool systems so I don't have to mess with a vacuum pump and refrigerant. The bedroom is around 240sqft and is extremely tight and well insulated and one 9k unit will be dedicated to that space alone. During daylight hours it will condition a wider area. A second unit will condition air in the living room areas at the other end of the house during the day as well as the third unit for the kitchen dining office area. The third unit will be grid connected and won't be a load on my batteries. So I'm looking at having two 9k mini splits on battery. Based on an average of your experience and the experience of @brandonboosted I'm probably looking at somewhere in the neighborhood of 12-18 kWh overnight need to be safe?

 

[Partimewages]

Not to be negative or disrespectful but the answer to OP's question is open ended. It will depend on where he is located. If it's 15 degrees outside and your inside is maintaining 70 it will be more watts per hour than if the outside is 40. The mini is a variable capacity so watts per hour are dependent upon many variables.
We in Central Ohio spend 75% of our energy in the heating mode. But rarely see peak loads in either season.
You need to have a heating/cooling load run on your home to get the correct figures and size of equipment.

 

[Ampster]

Right now I'm looking at the MrCool systems so I don't have to mess with a vacuum pump and refrigerant.

I was going to do that but decided I wanted one compressor to run three head units for simplicity. It saved enough money that a $100 vacuum pump and some parts were worth it for me. I stayed within the length of pipe in the specs for that compressor so I did not have to add refrigerant. My next three head units have longer runs so I am going to watch a lot of YouTube videos about adding refrigerant for those longer runs.

 

[Ozark Tinkering]

I was going to do that but decided I wanted one compressor to run three head units for simplicity. It saved enough money that a $100 vacuum pump and some parts were worth it for me. I stayed within the length of pipe in the specs for that compressor so I did not have to add refrigerant. My next three head units have longer runs so I am going to watch a lot of YouTube videos about adding refrigerant for those longer runs.

I would do the same thing...15 years ago. Now my DIY projects have to be more plug'n play. I'll be lucky not to have to hire an "un-boxer"

 

[Ozark Tinkering]

The average daily consumption has been between 4-6 kWh per day.

So was that with 2 units running? How many hours?

 

[RV10flyer]

My Ameristar 12K 15 SEER Mini HP's pull 4.4A at 240VAC. I'm getting ready to install a Fujitsu 33 SEER 9K Mini HP, running on 240VAC. I'll have more data later on that and an Ameristar 9K 22 SEER 120VAC Mini HP. Plan on 6-10 kWh per day, with a lot of variables.

 

[Ampster]

So was that with 2 units running? How many hours?

I don't know because they are variable speed and are very quiet. As @Partimewages said, a lot depends on ambient temperatures. My evening lows have been 36-40 F and daytime highs 60-65 F/

 

[Ozark Tinkering]

Not to be negative or disrespectful but the answer to OP's question is open ended.

Actually I was pretty specific. The keywords being "watt hour meter"

My question is, has anyone here ever put a watt hour meter on a 9k or 12k btu unit to see how much power is required on an hourly basis?

I can figure out how well someone else's climate situation lines up with mine well enough to figure out if I will do better or worse based on my conditions. I'm looking for watt hour usage per day.

 

[Ozark Tinkering]

I don't know because they are variable speed and are very quiet. As @Partimewages said, a lot depends on ambient temperatures. My evening lows have been 36-40 F and daytime highs 60-65 F/

But both units were in operation at the same time?

 

[CamoGreg]

I ordered a new Pioneer 9K BTU that should arrive next week.
Mine is going in a RV bedroom where there happens to be a good place to mount both inside and out units. I also have an open 20amp circuit for a 120V clothes dryer that isn't used.

22.5 SEER
PIONEER Air Conditioner WYS009AMFI22RL Wall Mount Ductless Inverter+ Mini Split Heat Pump, 9000 BTU-110/120V https://www.amazon.com/dp/B01DVW6BGU/ref=cm_sw_r_awdo_471GMSSY7RP1MN66MMJ0

My goal is to be able to keep the bedroom cool running off the batteries through a good part of the night. Also ordered a Kwik-evac kit from Pioneer to give it a try. I've done auto system recharging and still have the equipment. But I haven't kept up on the reclamation requirements to have used any of it recently. I'll give it a whirl and if I fail, I have a couple of HVAC buddies to call on for a favor.

 

[CamoGreg]

Hoping this summer isn't as smoking hot as the last.
Soil temp chart from last year for an idea just how blistering it was.

 

[OzSolar]

Why guess when you can actually pull the specs and see what it does at various outdoor temps? Here's part of the the answer: https://mrcool.com/wp-content/dox_repo/mc-diy-es-ss-en-01.pdf

The spot I circled in red shows that when it's 32F outside and 65F inside the 12,000 BTU nominal rated unit uses 930 watts (input) and has a total capacity (TC) of 9,390 BTU's.


That link has the same chart for cooling.

The other part of the answer is that you are going to have to take your best guess at how many hours per day it's going to run at what temp. A good starting point to take some notes about how long your current unit runs at particular temps. That combined with the BTU rating of your current unit will get in you in the range. It's not going to be an exact number but you'll be in the ballpark.

 

[Ampster]

But both units were in operation at the same time?

Yes, both head units with the single compressor. The head units don't take much energy because they just run fans.

 

[Wet1]

I fully agree this IS a fairly open ended question. So many factors come into play... Equipment efficiency, insulation, room size, sun exposure, number size and quality of windows, air tightness, climate, thermostat set point, sizing of the units for the area, etc. Also, AC verses heating is a huge difference!

In the summer my Fujitsu 12k mini split uses very little in AC mode to cool a roughly 700 sq ft area. But trying to say how much it's drawing at any one time is hard to say as time of day, temp delta, and the variable speed compressor have instantaneous wattage all over the map. Living on the CT coast, I'd guess it probably uses on average about 3-4 kwh per day with a temp set point of around 72F (again in AC mode). Heating is a very different animal. I typically don't use mine past Nov as temps well below freezing start to really draw a lot more electricity. I ran it all through Nov this year to heat that same area and found on average it was drawing about 10-13 kwh per day being set at 66F-68F. I think my average temps for that time of year are probably around 50F or so during the day and around 40F at night. I'm sure in the dead of winter it would likely consume at least twice that, but I've never checked to confirm as I heat with wood or NG then. But again, this is specifically for my setup, YMMV!