I've been lurking in the shadows on this forum for years, not able to play because I wasn't burning wood, but hopefully next winter will be a different story. I'd like to do this install myself as many have done on this site, all I have are the schematics from Tarm's site which appear detailed enough, but where do I get these components online? If I go with local supply houses they might go "huh?" This is a hush hush system in WA, I'm sure the PacNW will be the final holdout against wood fired central heating. Anyway I don't have any wood boiler brilliant minds to pick around here, its all clandestine. I'm looking at a two boiler system as I'm adding the EKO onto my existing electric boiler system. We have 3400 sf of 4" radiant slab that I would like to use as the thermal storage allowing the boiler to run full on with all zones open until the burn is over, so I need controls and components to override the existing Tstats to open all zone valves whenever the wood boiler is running, then revert back to the existing electric boiler until another fire is lit in the EKO. This would no doubt cause temperature oscillations, but I think I could deal with that in lieu of water storage for now (if that makes sense?) Would someone be willing to share their wisdom and a good reliable parts list to add this boiler onto my existing system? Thanks for anything! Here are the components listed on woodboilers.com (tarm) the design I've been looking at is a .pdf on the same site "two boiler Primary Secondary Design No thermal storage" http://www.woodboilers.com/admin/uploads/public/WoodBoilerPlumbingSchematic0111Web.pdf Termovar Loading Unit - Integrates the Termovar Tempering Valve, a balancing valve, 3 thermometers, and a Grundfos 15-58 3 speed circulator in a compact solution. Includes ball valve isolation unions. Termovar Tempering Valve - Automatic, thermally operated valve that ensures a minimum return water temperature to the boiler, which increases efficiency, prevents tarring, reduces thermal shock, and increases the life of the boiler. Includes ball valve isolation unions. Automag Zone Valve - Normally closed 24 VAC 1” zone valve designed for continuous power supply. This valve is used to provide the code required heat dumping zone during loss of power situations. Honeywell AT72D Transformer - 40 VA Multi-mount transformer. Plate, foot, or knock out mounting. Primary 120VAC 50/60 Hz nine inch leads. Secondary 24 Vac secondary uses two screw terminals. Provides a power source for Automag zone valve. BLT Control - A tidy UL approved control with simple instructions that makes integrating a wood boiler and heat storage tank with an existing boiler a snap. The control includes an on/off switch and a three position switch that includes wood only operation, back up only operation, or wood with automatic back up operation. Integral diagnostic indicator lights simplify trouble shooting. Honeywell L4008A 1015 Aquastat - Breaks on rise 100-240F w/5-30F adjustable differential. 66 inch capillary. Tank mounted, this aquastat is the switch that begins the automatic back up function when your tank is below your useable water temperature. Honeywell L4006A 1009 Aquastat w/ ¾” Well - Makes on fall 100-240F. Used to sense wood boiler supply temperatures by mounting in the supply pipe. Starts the backup burner when the wood boiler temperature drops (auto backup function for add-on wood boiler used without heat storage).