HVAC TECHS - On a quest for the correct mini split

silusbotwin

Well-Known Member
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.
So basically the ICM HPC just keeps the pressure up thus keeping temperature up as well, keeping the outdoor unit from getting too cold or freezing up?

Will this one do the job? http://www.amazon.com/ICM-Controls-Head-Pressure-Control/dp/B007EWXK36/ref=sr_1_5?ie=UTF8&qid=1426959434&sr=8-5&keywords=head+pressure+control

So if I'm understanding this correctly from the description, this control will allow me to both heat and cool in temperatures down to -40 degrees Farenheit by keeping the pressure up and the fan moving, essentially protecting against that frosting problem that you're experiencing? That would be PERFECT.

Again, thank you so much for your help.
 

silusbotwin

Well-Known Member
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.
That seems logical. So it isn't possible to install a HPC on an inverter? I was going to say maybe you should pick up an HPC of your own if so but if I'm understanding you correctly, you can't do that on an inverter, and of course you already knew that lol
 

silusbotwin

Well-Known Member
It would be even cooler (hotter if I was intending a pun) if you built an enclose that covered it and sealed completely and then hooked the louvres up to motorized hinges that were triggered by a temp probe. It would take some serious dialing in to ensure that you aren't smothering your expensive outdoor unit but it sure would be cool (again, by cool I mean awesome lol) to see that setup completely automated. Then if you ever shut the room down for a period of time, it would completely seal itself off from the elements, bugs, dirt, etc.
 

silusbotwin

Well-Known Member
The ICM HPC arrived in the mail yesterday and I have the same HVAC guy that I said I didnt want to bother, coming by to check it all out after I set it up. Hes going to check my work to make sure its all solid and the he is going to evacuate the lines for me, install the HPC (I dont wanna frig it up), and sign my warranty paperwork since it must be signed by an HVAC guy to keep the warranty valid. Wish me luck. The AC should be here by this upcoming Wednesday.
 
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.
Possible to,install a 2nd 6" at the end of your lights to help suck it out. Might help lower the btu nneeded for your ac
 

silusbotwin

Well-Known Member
Possible to,install a 2nd 6" at the end of your lights to help suck it out. Might help lower the btu nneeded for your ac
Funny you should ask because I happen to have 2 x 65" inline fans that I'm not using for anything else and my lighting consists of 2 x 4 light runs about 20 feet long so 2 x inline fans would be perfect to hook up at the end of the runs. I suppose as long as I seal the ductwork up really well and keep my massive carbon scrubber running, the pulling of air shouldn’t pull any smell with it. We shall see. I'll upload pics after I get everything done.
 
Funny you should ask because I happen to have 2 x 65" inline fans that I'm not using for anything else and my lighting consists of 2 x 4 light runs about 20 feet long so 2 x inline fans would be perfect to hook up at the end of the runs. I suppose as long as I seal the ductwork up really well and keep my massive carbon scrubber running, the pulling of air shouldn’t pull any smell with it. We shall see. I'll upload pics after I get everything done.
My llights are air cooled. Have the fans push through the hood,if. Smell is a big concern, pushing will cause a positive pressure in the hood not pulling smell from,in the tent/room into the line I have 2 pushing and 2 pulling. I have 0 smell
 
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