Cowper stove

The Cowper Stove Intake starts this build and is the front of the finished stove, where the furnace's exhaust arrives. Stoves are built in pairs; the loop they run and the heat they buy are on Hot blast.

Layers +2 to +3 (the same course)

#	Colour	Name	Matches
1		any Refractory bricks	game:refractorybricks-good-tier*
2		Cowper Stove Intake	smex:cowperstove-intake*
3		Pipe Outlet	ppex:pipe-outlet*
4		Pipe Passthrough (Straight)	ppex:pipe-passthrough-*
5		Heat Sink	smex:cowperstoveheatsink*
6		Iron hatch door	game:cokeovendoor*
7		Empty (air)	game:air
8		Empty (air, or a pile of coal)	@(air|coalpile)

Every block is drawn in its default orientation: the layout carries no facing data, so the build order below names the facings.

Materials

Block	Cells
any Refractory bricks	48
Cowper Stove Intake	1
Pipe Outlet	2
Pipe Passthrough (Straight)	1
Heat Sink	4
Iron hatch door	1

The shape of it

A stove is a three by three brick tower, seven levels tall counting the floor, with four Heat Sinks stacked in the middle column and four gas fittings in two pairs. The Cowper Stove Intake is the control block and the front of the building.

where	what
the cell below the intake	left open, for the coal pile that speeds charging
the intake block itself	front, at floor level: furnace exhaust in
one level above the intake	front: the outlet that gives hot blast out
the back wall at the intake's level	the outlet that sends spent exhaust on
the back wall one level up	the passthrough that takes air in from the blowers
the middle column, the intake's level and the three above it	the four heat sinks
the side wall at the intake's level	the Iron hatch door

The table is the whole of the plumbing: the furnace's gas goes to the front pair, the blowers' air to the back pair, and each pair has its inlet and its outlet at different levels. Swap the levels of a pair and the stove will charge and never blow.

Build order

1. Pick a spot beside the furnace with room for two stoves and the pipe between them, and with the smoke stack reachable from both.
2. Place the intake facing the way the exhaust main will come in. It is the control block, so its facing fixes the stove.
3. Hold ctrl and shift and right-click it for the build outline and the chat list of what is still missing.
4. Lay the floor and leave the cell directly under the intake empty.
5. Stack the four heat sinks in the middle column, starting at the intake's own level. A stove built without them has to be taken apart again; they are the whole of the machine.
6. Set the Iron hatch door in the side wall and the three pipe fittings in their cells: the hot-blast outlet above the intake, the air passthrough high at the back, the spent-exhaust outlet low at the back.
7. Build the walls up and cap it. Any refractory tier is accepted and they can be mixed.

The first charge

1. Pipe the furnace's exhaust main to the intake face, with a valve in the line.
2. Pipe the hot-blast outlet above it to the tuyeres, with a valve.
3. Pipe the blowers to the air passthrough at the back, with a valve, and the spent-exhaust outlet at the back onward to the Smoke Stack Intake or the next stove.
4. Run the furnace on cold blast until it is melting. A stove has nothing to charge from until the furnace has been alight for a while.
5. Open the exhaust valve only. The panel reads "Heating Up!" and the heat sinks climb; look at one to read the temperature. With no coal below, the core closes half the gap to the exhaust in about ten minutes; with coal it is under three.
6. Shut the exhaust valve and open the air valve. The panel reads "Heating Air" and the furnace picks up the boost.

Build the second stove before you rely on either: a stove that is blowing is a stove running down, and the pair alternate. The loop, the rates and the ceiling are on Hot blast.

What goes wrong

"Cannot heat up, exhaust mixes with the air!" Both of that stove's valves are open. One at a time, exhaust first.

Built without heat sinks. The multiblock will not complete, and the outline will say so; if the build was finished some other way the stove has nothing to store heat in.

The two back fittings swapped. The passthrough is the air inlet and goes high; the outlet is the spent-exhaust exit and goes low.

No overflow line to the stack. Shutting a stove's exhaust valve leaves the furnace's flue gas with nowhere to go, and a choked furnace stalls. Build the overflow before the first swap, not after the first failure.

Split output networks. If each stove has its own pipe to its own tuyere, the blast temperature collapses on every swap. Merge the hot side so both tuyeres draw from the same pipes.

A stove that will not reheat. Shutting the air valve leaves gas standing in the passthrough; the stove vents that itself on the next tick and charges from the one after. A stove that stays on "Cannot heat up" has an air valve still open.