HVAC TECHS - On a quest for the correct mini split

[silusbotwin]

I am currently searching Amazon for the right mini split to replace my 2 x 1-ton dual-hose portables in order to cool a 10'x20' 8 x 1000 watt lights in a NON-INSULATED PLASTIC-SHEET-WALLED flower room, preferably allowing me to remove the glass and disconnect all ducting from my 6 inch air cooled hoods to run in a bare bulb/sealed room configuration. Now that Spring time is almost here, signalling that Summer is right around the corner, I need to get this ball rolling asap before these wicked temps kick in. The portables worked very well to keep things cool last Autumn but I know 24000 BTU's of portable is NOT going to keep things cool during the summer temps. There is just way too much ducting + port holes + inline fans needed to keep these 8 lights properly cooled through inline fans and duct work so I would like to just do away with all of the air cooling stuff on the reflectors. I have exactly $1350-$1400 to spend so I have been looking at these Pioneer units at:

http://www.amazon.com/Pioneer-Conditioner-Dehumidification-Ventilation-Installation/dp/B0095VEJ2K/ref=sr_1_1?s=home-garden&ie=UTF8&qid=1426845129&sr=1-1&keywords=pioneer+24000+mini+split

and I have a few questions I was hoping I could get any or all of the following questions answered by an HVAC tech or a savvy DIYer:

1: What exactly is the difference between an inverter mini split and a regular mini split and which should I aim for? I noticed that the regular units are a bit cheaper than the inverter units. The price savings would allow me to include the vacuum pump and line set while still staying within my $1350 budget.

2: Will a 2 ton unit be sufficient for all 8 of my 1000's in a sealed room in a bare-bulb/non-vented/glass-removed completely sealed flower room in my Michigan basement (highs of about 105F in the Summer and lows of about -8F in the Winter but I don't have trouble keeping things cool in the Winter so I would be using heat pump mode only in the Winter)? Fortunately I already have an extra 1 ton Ideal Air mini split I could use to keep the common are in the basement cool on the outside of the flower room, while the 2 ton would serve to cool the inside of the flower room where the plants will be growing.

3: Have you heard anything about the quality of the Pioneer units? Looking at the 1000+ reviews across all of the Pioneer mini splits on Amazon, they average out to a 4.5/5 star rating all across the spectrum of sizes. It seems they are within my budget and still great quality. I know, I know Mitsubishi is most desired but I just can't afford a Mitsubishi and still get the cooling capacity that I require.

4: Can I trust the Harbor Freight vacuum pumps and line sets or are they going to burst and cause me to lose a hand to refrigerant induced frostbite?

5: Do you know if this unit is capable of alternating between heating and cooling modes without any user interaction, or do I have to manually switch between heating and cooling when the temperatures outside swing dramatically overnight? If this unit does not automatically alternate modes, is there something I can hook up to make it happen?

6: Is there a particular sized vacuum pump and line set I am going to need to evacuate a 2 ton unit? I do not plan on altering the 13 foot long mini-split copper lines so I shouldn't have to remove any refrigerant or mess withany cutting/flaring tools at all. According to all of the reviews and the listing, everything needed except the pump and line sets are included in the purchase.

7: Is there any other mini-split that you know of that will do the job more sufficiently + whose low price will keep me covered on the cost of the pump and line set while still staying below my budget of 1350$ while still being a reliable quality unit?

I figure I can install and evacuate the lines myself since I cant have any HVAC tech's over into my spot for security reasons. I have done plenty of DIY mechanical work in my day, including installing newer upgraded 200 amp main service panels +breakers+new 110V and 220V circuits added on a few different homes, I have learned to operate a 100 foot 3/4" drain snake very well, built quite a few decent sized grow rooms by myself, and plenty of other residential home improvement projects, and after watching a good amount of mini-split installation+evacuating youtube videos I feel confident that I can pull this off by myself.

I greatly appreciate you taking the time to read up to this point. I realize it was a very long and drawn out post. Your karma will take a +1 stat increase for helping me out XD You must know that this is VERY important to me (obviously) and I am VERY grateful that you have taken the time to help me out. My whole life depends on me keeping my room running so you helping me is a pretty huge favor to me.

 

[mrblu]

your going to need like a 4 ton mini split for 8000 watts in lights to be really efficient. atleast 3 tons at the least. im afraid your going to need to up your budget if you want to cool that room in the summer time.

the usual guidline is like 4000 btu for every 1k watts of light, so by that math you would need atleast 32k btu.

 

[mrblu]

i also just paid 1800 for a quick connect 24k btu then the price went up by 450 dollars the day after i bought it. it was the aura 24k btu diy one. still waiting on the unit to arrive for my sealed room.

 

[silusbotwin]

I have managed to get my budget up to $1550 but it isn't possible to get it up any higher. Also, don't forget that I already have a 12000 BTU Ideal Air mini split just sitting around collecting dust. I realize there would be a higher cost of parts for installation since I would need to get either double the amount of wall mounts or some type of cement/stone pad for each condenser to sit on as well as double the amount of wiring and outdoor disconnect boxes but I should have enough money to cover picking that stuff up from the local Home Depot by the time the mini split unit arrives at my house.

Perhaps I should pick up a 24000 BTU and install both of them as well as keep the 6 inch air cooling fans and duct work in place, but right now I have 2 runs of 4 lights each, both runs being powered by a single 6 inch 425 CFM inline per run. The lights closest to the intake side of the sealed air cooling ducts stay pretty cool but you can tell the air inside is starting to heat up good toward the end of the run after the air has passed through 3 lights already and collected all of those 3 lights worth of heat with it. Perhaps I could install the 24000 BTU on the side of the room toward the end of the ducting runs and install the 12000 BTU on the side of the room where the fresh air first comes into the hoods?

It is proving very difficult to stay within budget while still managing to get the cooling I require but those Pioneer units are VERY cheap compared to other units on the market and they have nothing but rave reviews and reports of good customer support BUT they only go up to 24000 and they are only 13 SEER.

 

[silusbotwin]

Is that 32000 BTU estimate you gave based on non ducted bare bulb hoods or is that based on air cooling ducts and fans connected?

 

[silusbotwin]

Sure would be nice to get rid of the hoods and go vertical bulb but I would probably melt a hole in my neck seeing how clumsy I can be at times lol For now I think I'll just set my goals at 8kW horizontal mount inside hoods but without glass and venting. If I absolutely must hook up venting, I can, I just prefer not to since that requires 6 inch port holes drawing attention to neighbors in their backyards. I am trying to go as stealthy as I can and I dont think my neighbors would question a mini split condenser. I suppose I could hide a couple of port holes to keep one of my portables in the mix for a total of 36000 BTU of mini split and 14000 BTU of portable. That makes 50000 BTU total, I'm just trying hard to avoid keeping air pushing through 6 inch port holes.

I wish I could afford a 3 ton SO badly but I have to account for the extra fans I'm going to need to keep air circulating, wiring, disconnect boxes, a crappy vacuum pump and line set, etc. It's hard working with what ya got sometimes but it's what i got.

 

[mrblu]

yeh im going to go parazontal if the unit i got works well. right now im running a 14000 btu dual hose but im losing co2 like no ones business having to run air through my hoods also. im just running 3600 watts of light right now in my flower room.

im adding a 5x10 tent and moving my dual hose into it do increase my flower area in another room. so i can get up to about 96 plants in total in my perpetual.

im not sure on the bare bulb factor ive seen some people say 6k for each bulb to be sure but i have no actual experience. i will know in a few weeks.

its just hard to get my wife to ok me spending 3-4k on an AC thats not at home lol.

 

[mrblu]

i thought it was funny the aura 24k was 1800 dollars but after i purchased it the next day it was 2250 dollars.

 

[silusbotwin]

I feel your pain man, I've been keeping 8kW cool with just 2 x 14000 BTU dual hosers and it struggled hard during the hot days last year. I've seen a guy keep 6000 watts worth of1000 watt open hoods at a steady 75 year round, even on the 100+ degree days. All because he had central air assisting him of course. It was the craziest thing I ever saw. He had at least 20 feet of ducting AND a stealth box AND he was pushing air through the exhaust system of his single dual hoser with a single six inch inline. Oh man how I would rejoice to have central air. I'm SO friggin tired of rebuilding every Summer and every Winter. I started this operation from 3 x 26 watt CFL's in a closet and just made sure to dump all of my money back into it every run. It has taken me four years to get up to where I am. The funniest thing of all is that when I had 2000 watts I thought "gee golly I cant wait to get a 14K portable", then when I got the portable and upped the lighting to 4000 watts I thought "Gee golly I cant wait to get another portable" and then when I got a second portable I thought "Gee golly I cant wait to get a mini split" and now that I have 2 portables and a 12000 btu mini with 8000 watts of lighting I thought "Gee golly I cant wait to get a large mini split" and now that I'm ordering the bigger mini I think "Gee golly I cant wait to get central air someday" lol When does it end? lol

 

[silusbotwin]

Sounds like you got the serious hook up and the universe gave you all the luck to get that deal. I know that some mini split sellers will offer a lower price if they dont have it in stock yet and then they raise the price quite a bit as soon as they buy it and have it in stock.

Good luck and god speed in dealing with the wife. Maybe try to get her to understand the cost versus the return. It REALLY is a GREAT investment.

 

[nevergoodenuf]

Why don't you sell the IdealAir and add that to your total. You should be able to get one then. If you can afford it, get the highest seer unit you can. That along with no fans cooling the lights, your electricity shouldn't go up much. I have a 110v 12,000 btu Ideal Air with heatpump. If you get a wall controller that switches from heat to cool, you can then set temperature ranges that it will come on at.
http://www.minisplitwarehouse.com/product/midea-30000-btu-220v-dc-inverter-16-seer-mini-split-heat-pump-ac
http://www.minisplitwarehouse.com/36000_Btu_Ductless_Mini_Split_Heat_Pump_AC_with_Mitsubishi_Compressor/p315964_7294112.aspx

 

[Resinxtractor]

You need 6000 btu per 1000. Then add about 2000 for the dehumidifier and another 6000 for the room it's self. If you live where outside temp gets below zero do not buy an inverter mini split it will not run and will automatically run in safe mode. If you buy a standard mini split you can get head pressure controllers installed and run well below -30.

 

[silusbotwin]

Why don't you sell the IdealAir and add that to your total. You should be able to get one then. If you can afford it, get the highest seer unit you can. That along with no fans cooling the lights, your electricity shouldn't go up much. I have a 110v 12,000 btu Ideal Air with heatpump. If you get a wall controller that switches from heat to cool, you can then set temperature ranges that it will come on at.
http://www.minisplitwarehouse.com/product/midea-30000-btu-220v-dc-inverter-16-seer-mini-split-heat-pump-ac
http://www.minisplitwarehouse.com/36000_Btu_Ductless_Mini_Split_Heat_Pump_AC_with_Mitsubishi_Compressor/p315964_7294112.aspx

I thought about that as well but if I'm going to be selling it, I will have to use the money for other things. I would rather keep it. I can keep my lighting ducted and cooled if need be so 4000 x 8 = 32000. The two of them together should do the trick.

 

[silusbotwin]

You need 6000 btu per 1000. Then add about 2000 for the dehumidifier and another 6000 for the room it's self. If you live where outside temp gets below zero do not buy an inverter mini split it will not run and will automatically run in safe mode. If you buy a standard mini split you can get head pressure controllers installed and run well below -30.

I actually have the inverter version in my cart and I was just about to place the order so I'm glad I noticed your post first. Thanks!

If I were to buy the head pressure control here:

http://www.amazon.com/ICM-Controls-Head-Pressure-Control/dp/B007EWXK36/ref=sr_1_7?ie=UTF8&qid=1426933436&sr=8-7&keywords=head pressure controller

Do you think a decent DIYer could figure out the operation? Is there any danger of this controller damaging the unit if I don't understand its operation right away and have a bit of a learning curve? Anything else I will need to install it aside from wiring, like any valves or would I be able to install it as it is and run it?

I was under the impression that the inverter units had a sort of a toaster built into the condenser to allow for winter time operation, is this incorrect? It does get VERY col in the Michigan Winters (down to the -20's) so the head pressure controller might be perfect in my case.

 

[jijiandfarmgang]

My two cents......take it or leave it

I'll start off by saying I'm not an HVAC tech or specialist

If your running a 8k bare bulb setup by yourself and you cant scrape together money for a proper cooling setup, your doing something wrong...no ifs ands or buts

Possibly think 4k setup this year

Bare bulb is better, but if you can't cool it, why the hang up on it? air cool them hoods

high seer is great........but this is more for in residence use, most commercial splits have a low seer

5: Do you know if this unit is capable of alternating between heating and cooling modes without any user interaction, or do I have to manually switch between heating and cooling when the temperatures outside swing dramatically overnight? If this unit does not automatically alternate modes, is there something I can hook up to make it happen?

I have no idea, but most are. Although the hysteresis isn't usually adjustable or conducive for a growing environment.

- Jiji

 

[Resinxtractor]

I live in michigan as well. I consider myself an advanced diyer. I am no hvac tech but do understand refrigeration and electricity well. All you will. Need is some 12 gauge stranded wire, crimp connectors, wire strippers/crimper, and a 24v transformer like for a door bell ringer. Follow the instructions for the controller and set the dials for the middle of the road settings. Also make sure you vacuum the lineset and use blue nylog on the threads of all lineset connections. I bought the nylog on ebay and also picked up the ideal air mini split install kit. Comes with everything you need to book up the lineset correctly.

I would do some research and get familiar with how these units work and how refrigeration works. You can't really call a hvac pro unless you are comfortable letting strangers in your grow if you have a issue.

 

[silusbotwin]

My two cents......take it or leave it

I'll start off by saying I'm not an HVAC tech or specialist

If your running a 8k bare bulb setup by yourself and you cant scrape together money for a proper cooling setup, your doing something wrong...no ifs ands or buts

Possibly think 4k setup this year

Bare bulb is better, but if you can't cool it, why the hang up on it? air cool them hoods

high seer is great........but this is more for in residence use, most commercial splits have a low seer



I have no idea, but most are. Although the hysteresis isn't usually adjustable or conducive for a growing environment.

- Jiji

Not everyone runs larger scale residential operations for the purposes of making as much money as possible. I am extremely generous and I only do this so I can do what I truly love while providing my family with a comfortable living, and also being able to offer my patients high quality meds MUCH cheaper than anyone/anywhere else in my state offers. If I told you what I accept for donations, you would probably want to slap me lol

With that said, It's not that I can't air cool the lights, it's that I prefer to keep it bare. Seeing as how air cooling will put my BTU requirements below what I can afford to buy (8 lights x 4000BTU = 32000 BTU) (1 x 12000 BTU unit + 1 x 24000 BTU unit = 36000 BTU's total, keeping my heat production under by 4000 BTU's).

You make perfect sense as far as keeping the air cooling running to add a bit of heat extraction and that is what I believe I will do. I haven't BEEN running 8 lights all along BTW. I have ran 4K for about a year and was finally able to find the time and extra funding to double up my operation up to 8K. This will be my first Summer running 8K, and I have only had a single winter crop under my belt with it, and I am trying to keep the price low. I can be a very frugal person, but there are many expenses I am not looking to get rich. I am looking to help as many sick people as I possibly can at a rate they can actually afford.

As for the hysterisis, I wont lie, I have no clue what that means or what you're getting at lol. I do appreciate the input though. Growth is achieved through constructive criticism. It would be different if you were just a rude butthole trying to be mean but I get the vie that you're simply trying to help, just like I asked Thank you! In regards to your two cents, I will certainly take it

 

[silusbotwin]

I live in michigan as well. I consider myself an advanced diyer. I am no hvac tech but do understand refrigeration and electricity well. All you will. Need is some 12 gauge stranded wire, crimp connectors, wire strippers/crimper, and a 24v transformer like for a door bell ringer. Follow the instructions for the controller and set the dials for the middle of the road settings. Also make sure you vacuum the lineset and use blue nylog on the threads of all lineset connections. I bought the nylog on ebay and also picked up the ideal air mini split install kit. Comes with everything you need to book up the lineset correctly.

I would do some research and get familiar with how these units work and how refrigeration works. You can't really call a hvac pro unless you are comfortable letting strangers in your grow if you have a issue.

Fortunately I already have all wiring, connectors, crimper, and I even have an old 24V transformer still connected to the basement floor joists from the old doorbell that was in my ancient Detroit house, so that works out well for me So the wire MUST be stranded? Can't use solid? So middle of the road settings meaning right in the center of the dials upper and lower limits? It shouldn't need to be adjusted from there? I suppose I should just wait and see what the instructions say when I get them lol. I have a vac pump, lineset, nylon and leak sealant in my Amazon cart. Now I'm just waiting until I feel 110% comfortable before I pull the trigger and pay. I want to make sure I get EVERYTHING I need in one shipment. It's going to take almost 2 weeks for the AC to arrive and I want to be able to install it right away without waiting for more parts to come from Amazon or somewhere else on the interbutt.




Apologies for the huge amount of text I'm about to share but I figure it may be best to just copy and paste what I already typed out in a different forum so I can get you up to speed on where I stand. The following is a response I posted in response to another fella who offered some advice and mentioned that the mini split should have a pressure controller built in. I dont think that fella knows much about HVAC stuff:

I am not an HVAC tech, but I live in the GHETTO where it's basically like the wild west. Aside from that, I have checked my city's code and it's all good for me to do it myself. Also, this particular unit uses R410a and from reading the MSDS sheets here: http://www.highseer.com/pdf/MSDS-R410a.pdf------- I got the impression that R410a is very friendly as far as the atmosphere/environment is concerned. I am confident in my awareness and consciousness for safety and I think I'll be just fine as long as those cheap line sets or pump doesn’t fail on me and spray me down with R410a lol

The user manual is here:

http://www.highseer.com/pdf/WYD_UIM_V0307.pdf

the installation manual is here:

http://www.highseer.com/pdf/WYD_UIM_V0307.pdf

and the service manual is here:

http://www.highseer.com/pdf/WYD-13SEER-SM.pdf

I am pretty sure there is no head pressure control built into the unit when I get it from the dealer. If I were to hook one up myself, is there a possibility of causing damage to the HPC module or condenser by making a mistake during dialing it in? A chance of an exploding flare connection perhaps?

What exactly would the advantage of cutting the heat pump off at a certain low temp be? A safety measure to prevent damage to the condenser when it gets too cold? The thing is that I may need to heat and cool during outside sub-zero temps and it seems like the head pressure control I mentioned earlier would cover it down to -40F while the unit as-is from the dealer only operates down to about 15-20 degrees Farenheit according to HighSeer


EDIT: Nevermind, I see what you're getting at. I noticed that the pressure control I linked earlier is only for heat, not cooling. So I will have to get a controller that does heating and cooling that is still compatible with that particular conditioner.

I might not be an HVAC tech but I am certainly a Jack of all trades and I have watched/assisted many repair and install jobs. I might not know how to do something before I start but I make sure to read ALL user, service, and technical manuals about stuff, I spend a good 40+ hours researching a project before I even start, and I have done many many different odd jobs around my house and other's. I have installed main service panels, sub panels, ran new circuits both 110V and 220V. I have replaced water heaters, receptacles, small runs of gas lines flaring included. I have carried out minor repairs on all different types of electronics all my life, video game consoles, home stereos, car audio installations, etc, my speciality being computer repair/builds/software. I have had vocational electronics training (although that was almost 15 years ago and I have forgotten more than I remembered). I have worked in a ridiculous amount of industrial jobs, mostly steel processing/fabrication shops, automotive assembly, and I used to run a sort of pseudo business repairing peoples electronics on Craigslist and the like. I guess what I'm getting at is that I realize that a mini split system isn't all electrical work and there are high pressure gas lines involved, but I am very confident in my abilities after researching thoroughly for about 60 hours over the last two weeks.

I have a couple different Fluke meters and plenty of tools and if there is a tool I dont have, I have an HVAC tech in the family to borrow them from. I would ask that same family member all of these questions but I would rather keep this out of his ear due to the clandestine application I'm using it for.


If you have made it this far, I am eternally grateful. My whole livelihood depends on my making this thing work. Seriously. I just want you to know you have my sincere thanks.

followed by:

I understand an inverter system simply regulates the condenser fan in a different way that prevents big swings in fan speed, bringing the room to desired temps and then slowing down to keep a light conditioning maintaining the room temperature but is that it? The only difference. The only reason I was looking at the regular unit over the inverter unit is that another person in a forum I posted in (I was referring to you resinxtractor) seemed to imply that inverter units do not allow for the utilization of pressure controllers. Care to speak on that?

Again, I apologize for the huge amount of reading above but I spent so much time typing it all out I didn't want to do it all over again.

 

[Resinxtractor]

The inverter units regulate the compressor speed and not fan speed. They are "smart" and most units will tell you outside temp on the indoor display. If temp drops below zero the unit will shut down. Nothing you can do. I have both an inverter 24k unit and a standard 18k unit. The 18k unit has been running since August of 12 and I relocated it to a new garden a few months ago. The last 2 winters have been brutally cold and summers hot as hell here thing is still kicking. The new 24k unit works well at temps above 15 below that cooling capacity is reduced due to frost building up on the indoor evaporator coil and going into defrost mode back and foth. 5 it will shut down completely. I did remedy this slightly by covering the intake side of the outdoor unit with plastic to reduce air Flow across the coil, but max cooling capacity was reduced.

During the summer the inverter kicks ass no doubt but for what we do a nd reliability overall the standard units with the icm module is the safest bet.

 

[Resinxtractor]

I will be building an insulated enclosure with small vent luvers around the inverter unit to use during winter. Hopefully that will make it run normal.