Since 315 is at Chama I guess that she would also qualify for this discussion. Remember now that 315 is about 1/2 the size of a K36/37. Since we only run her for special events, and not everyday, we have never ran into a 31 day inspection requirement with-in a "Annuals Year". We have however done the 31 day inspection, including boiler wash out on several occasions to be ahead of the game, and to maintain the high degree of preventive maintenance we set for her.
We typically ( as in right now ) when she sets unused for an extended time, drain the boiler and leave several of the lowest plugs out, and the monkey tail open for ventilation to prevent sweating, and keep it dry. For firing up, we practice the long and slow re-heat. We typically start with 3/4+ of a glass of water. We feel that it helps to even out the heat transfer to the top of the shell. The 315's fire box is long and narrow. We start with an even single layer of chunk coal over the entire grates, followed by scrap wood pieces over most of the bottom layer of coal. Using a garden sprayer with diesel, we soak the wood down good, Then add another lite layer of chunk coal by hand to place about the bed. Another spray of diesel all about to Finnish off. We use a scoop full of old oily rags, used up greasy gloves, soaked and lit up to get it going. After the fire lights off, if available we use external air for the blower, but very little, just to create a draft. We can use its own steam when it hits 25 lbs. During the ramp up we keep a small to moderate fire going. After the first couple of hours or so, We dump an amount of water out of the blow down, to stir the pot, and prevent stratification layers in the boiler. We prefer the 4-5 Hr route to full steam.
When done with our runs, and prepping for extended storage ( less then 90 days or so ) we fill the boiler full, and park her, and let the fire die overnight with the fire box doors closed. Long and slow cool down. Typically after breakfast the next morning, there is < 10 lbs. pressure in the boiler. We crack the monkey tail slightly, and bleed off the remaining pressure. We then dump the water using the blowdown ( 1-1/2" ) There is about 1200 gal in the boiler. This slowly lowers the water and the temp level. When empty we then remove the bottom boiler plugs and open the monkey tail to vent, and this drys the boiler out with its own heat.
