@Eiswald @Xenophon @Humpleupagus @d0c40r0 @ForbiddenDreamer @KingOfWhiteAmerica @catmanmancat Heat pump ebin. Stacks of PEX rings below the frost line (and another 3 feet down). PEX full of basically antifreeze water and alcohol. Closed loop to heat pump. It's like a hyper efficient AC because the ∆ is so low.