Anybody here install their own mini split A/C unit?

jonnynobody said:

My next upgrade will be installing a mini split A/C unit in my flower room which will allow me to seal the room with a co2 burner to increase production now that I am adding 2 high output LED quantum boards to my existing light setup. Without installing the mini split there is no effective way to seal the room while saturating it with co2 and cooling the room at the same time. A portable air conditioner is unfortunately not an option, because it's just sucking your co2 right out the exhaust. The co2 burner would just constantly fight the portable A/C in a power struggle to maintain balance. The result would be a very large electric bill, ineffective cooling, and excessive gas consumption. For those that are not familiar with what a mini split a/c unit is I will explain briefly. An air handler is installed inside the room on a wall. A line set runs outside to a condenser you mount on a little pedestal. Install a new circuit in your electric panel specifically for the mini split power supply. Run the power to a shut-off switch box in front of the condenser. The air handler within the room has no exhaust. It has no intake. It cools the air within the room it is mounted. It's also much more efficient in operation than a portable a/c unit.

I don't mind doing electrical work, but I generally stay away from getting into the panel. My neighbor is an electrician and offered to complete all of the panel work for me, and hookup the final connection to the condenser and shut-off switch box. I've watched several installation videos and it appears fairly straight forward. My question for people who have one or have installed one is this:
What is your electric bill like after installing the mini split versus using a portable a/c unit?
What advice would you give someone who is shopping for a unit or about to install one?
What issues (if any) did you run into while installing your unit?
Do you run co2?
How often does your burner kick on?

These units can be purchased between $500-$2500 depending on cooling needs. I have been told Toshiba makes the best units. That is all I know so far.

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Renfro said:

I have installed many mini's. Unless you are willing to purchase all the tools required you should just hire a licensed HVAC tech to do the last part. Buying the gear to do it correctly will cost as much if not more than paying a tech after hours to do a little work. Plus you don't void the warranty.

You could, without special tools, do the following:

Get the disconnect installed and powered up
Set the condenser unit and hang the air handler
Run the power lines from the condenser to the air handler
Run the line set (but leave the connections for the HVAC tech)

The HVAC tech should:

Check your work
Connect the line set at both ends
Pull a vacuum
Pressure test with nitrogen
Pull a vacuum
Release charge from condenser
Run and test the unit is operating properly

A typical setup the CO2 generator might run like 5 minutes every 30 - 60 minutes.

The absolute best mini's are made by Mitsubishi, period.

Make sure the unit has a low ambient rating that will work for you.

Click to expand...

piratebug said:

The "best" will continually change based on exactly what size area you are wanting to cool. And yes a ductless system is the only viable option if you plan on running co2 when it comes to the AC thingie. But even the most efficient systems are not as cheap to run as most people believe! Anyhow, lately I have been replacing many AC units with Geo Thermal Systems as that is where it is at today. Why, because they are much more efficient. and their running cost is less than 1/20th of what a comparable AC units running cost would be!

A 2 ton split AC units typical running cost...

15 amps x 240 = 3600 watts

3600 watts / 1000 watts = 3.60 kilowatt hours

Maine kilowatt hour cost = 14.90

3.60 kilowatt hours x 14.90 Maine kilowatt hour cost = 53.64, energy company rounds up = 54 cents per hour

54 cents per hour x 24 hours in a day = 12.96 per day running cost

12.96 per day running cost x 30 days average in a yearly calendar month = 388.80 cost to run every 30 days


And with a Geo Thermal System, you are only running a force feed priming pump that only runs until the cooling liquid reaches the exchanger, then its entirely gravity fed, so the entire system uses just 60 to 80 watts for the exchangers circulation fan, and that is it!

Click to expand...

Renfro said:

I have installed many mini's. Unless you are willing to purchase all the tools required you should just hire a licensed HVAC tech to do the last part. Buying the gear to do it correctly will cost as much if not more than paying a tech after hours to do a little work. Plus you don't void the warranty.

You could, without special tools, do the following:

Get the disconnect installed and powered up
Set the condenser unit and hang the air handler
Run the power lines from the condenser to the air handler
Run the line set (but leave the connections for the HVAC tech)

The HVAC tech should:

Check your work
Connect the line set at both ends
Pull a vacuum
Pressure test with nitrogen
Pull a vacuum
Release charge from condenser
Run and test the unit is operating properly

A typical setup the CO2 generator might run like 5 minutes every 30 - 60 minutes.

The absolute best mini's are made by Mitsubishi, period.

Make sure the unit has a low ambient rating that will work for you.

Click to expand...