Glad to find out that so many other people are working on walipinis.
Here in Minneapolis I've been working on one for several months that a great group of people got together and built this summer at a local church.
Ours is getting into pretty good shape now, but I'm having issues with water and with mold risk.
I'm trying to find a hand pump to pump out the water as it collects in the cold sink. For now I'm just bailing it out with buckets.
I found a hand-crank EZ pump on youtube that looks like it works, but people who bought it from Lehman's old-fashioned parts store have had issues with it and say it won't prime.
http://www.ebay.com/itm/Crank-EZ-Pump-Hy-Capacity-PN-8301252-/251699842901?hash=item3a9a7acf55:g:pE0AAOSwGWNUU-LI
I'm also concerned that with all the moisture the walipini will develop mold problems.
I just put in an ammo box stove - I wanted a rocket but some guy in my neighborhood had this one so I'm using it - to add heat during the cold Minneapolis winter - worked pretty well and is definitely helping with the moisture.
I'm trying to route the heat through the dirt walls to harvest some more of the heat into the wall - the ground is frozen but thawed when i put the smoke duct on top of it, so I'll try to bury it deeper and keep more of the heat.