Re: stack heater to speed draw
Here is a thought. Why not run a a black iron pipe ( about inch and a half or two inch ) to the bottom of each elbow to the fire box top with a steam valve in the middle of each so you can open it when you start your fire and close it when done preheating. That way no LP to worry about and I can't help to think that your preheat would go faster. As hot air razes threw the the fire box into the stacks to heat them causing the fire to burn a little hotter. I'm sure it would work,you just have to play around with the fire box vents and how far you open the steam valves to the vent. Or you could put a four inch piece of black iron pipe half way up with a four inch valve then T off from that with two inch black iron to the stacks. That's the way I would go. But if it's cheaper to go with the two valve set up, I'd go that way. Just a thought.
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