HVAC splits?

p0opstlnksal0t

Well-Known Member
Duct your air cooled hoods to where they aren't pulling air from in the rooms. Then once they're sealed you really don't need much btu of heat removal for a single 600w and 400w light. Exhausting the room atmosphere makes ac and co2 in their kinda pointless
 

Quintana

Well-Known Member
I would like to get a HVAC double split system and have already figured almost everything out about my install but these two things.
1. I can do all the work except refrigerant lines. I can't have a HVAC guy come into my rooms. He/she will need to do the evacuation and fill of refrigerant at the condenser outside. You supposedly have to have a cert to buy the refrigerant or I could do it all. :mad:
I want a condenser with two evaporators/controllers, for two rooms.

2. I already have a 220v wall socket on a 40amp breaker that's not being used in the space so I don't need to direct wire into the breaker box. Do the typical split condensers have a simple connection that can be wired into with a fat 220 elec. cable with the right 220v plug?
Not sure if Ideal Air is still doing DIY units, but they used to sell units that have a braided flex line from the outdoor unit to the head and a simple shrader valve that you teflon tape and screw on. They had multi-head units specifically for grow rooms and they ran on 110v. A nice DIY Unit for the money. Again, not sure if they're still selling them.
 

corncob ghetto

Active Member
Bwaaaahaaaa, most of what your hearing is chit. I've been a lennox dealer for 35 yrs. Mini splits run to 0 degrees ambient easy. Chit mines running and its 12degrees out. Power up outside condenser with 220 then run 3 wire split loom to each evaporator. Each has its own drain obviously. Just cut your lineset to size and reflare fittings, one lineset do both. Nitogen for flush and leak check, Pull vac and release charge. Depending on length may need freon. 410a freon at 3 oz per foot after 15ft of line..easy peezy done hundreds..... don't listen to half of these fartbags....bwaaaahaaaa
 

corncob ghetto

Active Member
The only real problem with most split AC units is they don't support low ambient temperatures. If it's gets lower than 60F outside the evaporator coil inside starts freezing into a block of ice. Sometimes you can install a freeze kit but it's not an energy efficient fix like the inverter style mini-splits have. On an inverter mini the power is converted to DC and back to AC to provide any frequency the unit wants in order to run the compressor and fans at variable speeds. When it's cold outside my mini's barely even run the compressor and the fans stop or barely turn on the outside unit.
Wrong
 

kingromano

Well-Known Member
outdoor unit will freeze by cold outside temperature in heat mode, it's normal

indoor unit never freeze in cool or heat mode. good brands evaporate at very low temps in cool mode, 2 degree C, sometimes 1 degree C, but never 0 otherwise it would freeze, like a cold room

in heat mode,the coolant is very cold when it comes to the outdoor exchanger, so it can recover calories from the air to heat your room
humidity contained in the outside air will condensate on the coils

all AC have a defrost mode, either by a resistance (old models) either by gas inversion
the overheated vapor will leave the compressor to go directly to the condenser and defrost the freeze around the condenser coils

past certains temps the efficency of the AC will decrease

in cool mode after 40degree celsius outside it become difficult to condensate the gas, the coefficient of performance will soar

same for heat mode, colder it is outside, more difficult it will be for the heat pump to recover calories outside to bring them inside
 

Houstini

Well-Known Member
Bwaaaahaaaa, most of what your hearing is chit. I've been a lennox dealer for 35 yrs. Mini splits run to 0 degrees ambient easy. Chit mines running and its 12degrees out. Power up outside condenser with 220 then run 3 wire split loom to each evaporator. Each has its own drain obviously. Just cut your lineset to size and reflare fittings, one lineset do both. Nitogen for flush and leak check, Pull vac and release charge. Depending on length may need freon. 410a freon at 3 oz per foot after 15ft of line..easy peezy done hundreds..... don't listen to half of these fartbags....bwaaaahaaaa
Don’t the Lennox mini-splits have a known issue cooling in low ambient temperatures? Maybe that has been resolved. After installing Lennox mini-split in a server room it would not operate below a certain outside air temperature. After much frustration of service techs, a Mitsubishi was installed as a replacement.

Do your research and verify that the unit will perform under your conditions. Not all mini-splits are created equal.
 

corncob ghetto

Active Member
Don’t the Lennox mini-splits have a known issue cooling in low ambient temperatures? Maybe that has been resolved. After installing Lennox mini-split in a server room it would not operate below a certain outside air temperature. After much frustration of service techs, a Mitsubishi was installed as a replacement.

Do your research and verify that the unit will perform under your conditions. Not all mini-splits are created equal.
Installed many in banks ,comp/server rooms .run all year and I live upper Midwest. Just don't buy cheapest stuff out there. They have come along way..
 

corncob ghetto

Active Member
Don’t the Lennox mini-splits have a known issue cooling in low ambient temperatures? Maybe that has been resolved. After installing Lennox mini-split in a server room it would not operate below a certain outside air temperature. After much frustration of service techs, a Mitsubishi was installed as a replacement.

Do your research and verify that the unit will perform under your conditions. Not all mini-splits are created equal.
What make a itchypussy better??? All about which one you buy.. lol. Lennox makes Low ambient models. More control over condenser with speeds on comp&fan, thus controlling freeze ups. Obviously not as efficient at these temps.
 

Houstini

Well-Known Member
What make a itchypussy better??? All about which one you buy.. lol. Lennox makes Low ambient models. More control over condenser with speeds on comp&fan, thus controlling freeze ups. Obviously not as efficient at these temps.
At the time, about 4 years ago, Lennox had no solution for low ambient temps for cooling, only for heating. If I remember correctly there was some sort of factory lockout below a certain temp for cooling mode.

Cooling efficiency would actually be increased in low temperatures. Heating efficiency is what goes down as it gets colder.
 

gwhunran

Well-Known Member
Update
I ended up getting two vertical type AC units. I had to cut holes in my wall as the units were 14.5" wide and the distance between the wall studs was 14.5". One fit like a glove, the other required removing some material from the studs. I ran two grows and both units performed perfectly and my elec cost were not much changed.
 

fatAngel

Well-Known Member
Nice. I installed a DIY Mr Cool Mini Split 12,000BTU by myself and I am somewhat handy. Whoever reads this, Mr Cool and other branded DIYs work and you don't need a professional to come out. I did every myself and I even borrowed the wrenches I needed from a neighbor.
 
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