EastTexCowboy
Solar Wizard
I actually have mine set at 75F but I have plenty excess PV so why not keep it cool in there. It's supposed to be triple digits here starting this week and going on for many days. Ugh. We'll see how it all does then.
Preparing for the heat...
- Thread starter Lt.Dan
- Start date
I have the 5000 btu window unit running on grid power right now (was spur of the moment install) but I'm planning on powering it with my dc system as I call it. Its a few panels with weize lifepo4 batteries and my old 4215bn's charge controllers powering it. I had added a gowise 1000 watt pure sine inverter onto that thing for the heck of it but never ran anything with it. The system provides the dc power for my house cameras, pi monitoring computers etc. With the gowise inverter just sitting there and being 1 foot from the outlet the window unit is plugged into its just screaming "Let me power it !!!!"
I just need to add a panel or two and I need to find my old pool timer since its the only thing heavy duty enough to safely switch the window ac unit on or off. I figure once I get it switched over to it I'll run the window unit wide open all day and have the timer turn it off at 4pm or so. That should keep the room cool since nights are not hot here.
I just need to add a panel or two and I need to find my old pool timer since its the only thing heavy duty enough to safely switch the window ac unit on or off. I figure once I get it switched over to it I'll run the window unit wide open all day and have the timer turn it off at 4pm or so. That should keep the room cool since nights are not hot here.
Robbert
Solar Enthusiast
Looking good! Also the lower temperatures will be better for the longevity of your batteries.
Smart investment.
Robbert
Solar Enthusiast
Installed mine mini-split in the garage in March. Consumption is going up considerably. The heat is just starting.....
Some tips from what I have leaned. I have a large off grid system. Each day we get close to 100deg but its also humid sometimes 70-80%. I insulated a battery room and also wanted to cool the inverters, batteries and controllers. Heat is bad not only for batteries but also electronics. All that stuff generates a lot of heat wow. I put a 14,000 btu AC just for a 4feet x 12 foot spot. IT does well in the day but at night things still climb. Batteries get up to 95deg at night which long term is not ideal.
I think in future I will up that and get a larger unit to really cool it all faster and colder all day. now its gets to 70deg in the room in the day. I think cooling all the batteries with my surplus power will make it all live longer. I run the AC 7am to 7pm and would like to change from 8am to 6pm so I dip into the batteries less.
For sure anyone off grid look into inverter AC units. They dont have that big amp pull when the compressor turns on or off. Most AC is full amps then off. The inverter units just cruse nice low watt.
I think in future I will up that and get a larger unit to really cool it all faster and colder all day. now its gets to 70deg in the room in the day. I think cooling all the batteries with my surplus power will make it all live longer. I run the AC 7am to 7pm and would like to change from 8am to 6pm so I dip into the batteries less.
For sure anyone off grid look into inverter AC units. They dont have that big amp pull when the compressor turns on or off. Most AC is full amps then off. The inverter units just cruse nice low watt.
EastTexCowboy
Solar Wizard
That seems off to me. Cooling 48 sf with a 14k btu AC unit, it shouldn't work hard at all. I'm cooling a garage that is almost 500 sf with 10' ceilings with a 12k btu mini split and it doesn't have any problem at all. I've raised the temp to 77F and the inverters and batteries stay nice and cool, even when the temps were over 100F and heat index was 116F, and our humidity is almost always high. If you're going to upgrade the unit anyway I'd say look hard at a mini split. It would also let you heat in the winter.
It gets to 68 inside the area. But after I shut it all off there is still some stored heat. If I can get it to 60 deg I think will keep things cooler over night. Works decent now but bigger AC I think work help even more. Can get things cooler faster.
Lt.Dan
Solar Wizard
I also am cooling a 500sf garage with only a 12k BTU, temps have creeped above 110* lately, but I will say, I'm only running it set at 80*.
During the hottest part of the day in the garage, which is 4pm, the mini split still isnt even at full speed. At night, it almost doesn't run at all, because temps drop far enough the mini split will shut off.
If you need 14k BTU for that small of an area, then like @EastTexCowboy said, there might be something wrong.
During the hottest part of the day in the garage, which is 4pm, the mini split still isnt even at full speed. At night, it almost doesn't run at all, because temps drop far enough the mini split will shut off.
If you need 14k BTU for that small of an area, then like @EastTexCowboy said, there might be something wrong.
Again nothing wrong. all day nice and cool. Im off grid so for 12-14 hours no AC. Different story if I had AC all night but that really cuts into the batteries. 6pm here is hot and humidity does make a difference even for batteries. All day I have 5 to 6 AC units running so the inverters are really working and making their own heat. Then I have about 300-400 amps of controllers that also generate heat.
Sounds like your grid tied if you have AC on at night cut the cord then you will understand when you live on batteries all night. ITs my lifeline and they are expensive so I want to keep them nice and cool as much as I can.
Lt.Dan
Solar Wizard
I run on battery all night too. But my loads are typically less than 400w. No heat being generated in the garage. Hence why the AC shuts off.
The difference of the batteries at 68*F and 80*F is not going to add years to the batteries life.
Run the ac on a timer. Thats how I have mine setup in my workshop. Run it for x minutes a few times during the night.
I would love 80deg but they spike up to 95-97 in the evenings when the ac is shut off. Problem too is the small enclosure holds in the heat. I have a small vent but does not really do it. I might put a good extractor fan to turn on automatic or put on a wifi control switch to pull air from outside. I pull 1500 to 2000 watts a hour all night.
I do that now in the LG app works great. All the AC in my house are on timers. Freezer and Fridge too. Tuya makes some nice 15amp wifi switches. Day time I have 26,000 watts to use so I freeze the house haha. Deep freezers on high. Then when sun goes down full conserve mode.
I meant for cooling the batteries and such. Just have it run for a bit different times during the night. Shouldn't kill the batteries and should lower the temps somewhat.
EastTexCowboy
Solar Wizard
Not grid tied in the traditional definition. Off grid with grid assist, but I almost never need the grid assist. Only after multiple rainy days in a row. But I do have 60kwh of batteries and my typical consumption on really hot days is around 70-75kwh. Every setup is unique but I think you'll find you can run a small mini-split for probably less than half what that 14k AC unit is using and keep it cooler. With the heat and humidity here my usage does peak around 3pm then stays fairly high until maybe 8:30pm then it starts dropping some. It's lowest from about 2am until 8am, but I think that's going to be pretty common for anyone with similar outside temps.
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