Downfalls for Solar Panels for Mini Split HVAC system?

TampaSolarPanels
TampaSolarPanels Registered Users Posts: 1
edited October 2018 in Solar Beginners Corner #1
Curious to find out if anyone has done a DIY and sourced there own parts for a Mini split hvac system and can assist with pointing out potential downfalls/hardships? The goal of this would be to run an HVAC system "off grid" and "remotely".

Comments

  • WaterWheel
    WaterWheel Registered Users Posts: 385 ✭✭✭
    edited October 2018 #2
    Several people on this site have done it.     My installation took me about 10 hours but I wrapped the lines with extra insulation and was working without help.

    Plan of upping your batteries and maybe your panels if you're going to run the mini-split several hours after sundown.
          
    In my case (1600 sf fairly well insulated old farmhouse) with the thermostat set at 75 we found that with a 18,000 BTU, 21 seer, 2 head Panasonic unit the batteries take a beating if you leave it running 24/7 so for AC we turn ours on about 10:30 am and off at about 10pm (outdoor temps in the mid 80s until 11 pm some nights).      If it looks like it's going to be a cloudy day we'll delay cutting it on until early afternoon, the programmable remote helps with this.

    Using the self clean mode allows the fan to run but not the compressor for an additional 30 minutes allowing you to capture every last bit of cooling effect with little battery drain or you can just leave it in fan mode for a breeze all night but we just use the ceiling fan for overnight cooling.

    We've used the mini-split for heat (set at 65 degrees), it's not too bad on the batteries overnight on nights when it drops to 40 degrees outside  and we just don't want to run the woodstove.      Just for testing I used the mini-split overnight once when it was about 6 degrees outside.        It couldn't quite keep up and the house dropped to about 58 degrees inside and the batteries dipped to 65% SOC by 5:30 am.       Generally we'll use wood at night and maybe use the mini-split for heat from noon to early evening if needed.      There is a fair amount of thermal mass around the wood stoves and the bricks put out heat for several hours after the fires are out.

    Conext XW6848 with PDP, SCP, 80/600 controller, 60/150 controller and Conext battery monitor

    21 SW280 panels on Schletter ground mount

    48v Rolls 6CS 27P

  • oil pan 4
    oil pan 4 Solar Expert Posts: 767 ✭✭✭✭
    There are solar panel boosted splits available.
    I don't know how a normal inverter split would handle the wide range of voltage panels like to put out.
    To be able to pump solar power straight into a split it has to be an inverter split, then to get one that can take solar panel power only costs marginally more.

    Solar hybrid gasoline generator, 7kw gas, 180 watts of solar, Morningstar 15 amp MPPT, group 31 AGM, 900 watt kisae inverter.

    Solar roof top GMC suburban, a normal 3/4 ton suburban with 180 watts of panels on the roof and 10 amp genasun MPPT, 2000w samlex pure sine wave inverter, 12v gast and ARB air compressors.