Ash pan liner

[johnp]

What can I line my ash pan with?

[fredrosse]

Ash?
I think there have been a few discussions on this forum about ash pans already.

[Lopez Mike]

What kind of a boiler?

I have a VFT and mine is lined with ashes. I empty it once a year whether it needs it or not.

Seriously, mine is sheet metal over about 3/4" to 1" of some sort of insulation, maybe ceramic wool or fiberglass, and another layer of sheet metal under that.

There are other solutions including keeping it wet. Mine works fine though.

Mike

[johnp]

Its a water water tube boiler, i just added a 1/8" plate under the grate but you got me thinking about adding insulation and another plate. I,m concerned about the sheet metal distorting, i guess i should line the sides and back the same way. Plate insulation and plate/lagging. Would stainless take the heat better.

[Lopez Mike]

I don't enough about water tube boilers to even sound ignorant.

S.S. doesn't corrode as much as regular stuff. As far as heat issues, as far as I know, S.S. is steel with some chromium added so that there is an extremely thin layer of chromium oxide which reforms as soon as it is abraded. That is, as long as there is Oxygen available. That's why we are careful about where we use it below the water line. It need access to air or water that has air (Oxygen) in it. If you want true resistance to corrosion, use a copper alloy like Monel or Bronze.

Mike

[johnp]

I'm more concerned about distortion, the first 6 or 8 inches are fire are fire bricks the. The rest of the walls and ceiling would be sheet metal insulation (mill board) and then sheet metal.

Sounds like I should do the same with the ash pan.

[DetroiTug]

It's been my experience with fireboxes, woodstoves, etc, the bottom below the grates does not get very warm. Especially if the cold air draft is coming in the ash area and not through the door. Heat rises. Plus a layer of ash is an insulator itself. I have painted floor boards butted right up the ash pan area on the outside of the boiler and there is no evidence that they have been subjected to any heat at all. And this boiler gets fired HARD. Someone asked me about how I tend the fire, I replied: "It's easy, if I can fit a stick of wood in, in it goes, and if I want add some and it won't fit, I stoke it and make it fit"

BUT, no two boilers are identical in their set up and how they are fired etc. So, do some testing to be sure.



-Ron

[Lopez Mike]

Ron,
Have you thought of or have you all ready insulated your steam line? Seems like it would be worth it.
Mike

[DetroiTug]

Have you thought of or have you all ready insulated your steam line?

That's an old picture. I look at that and shake my head, so much has been added and changed since then. Seems like a beginner getting a system operational is about 25% of the job, the other 75% is tweaking it. We sometimes take piping and insulating etc for granted, it's a lot of work and time consuming.

If I build another and I want to, hopefully with the experience I've garnered it will be 75% to start with.

-Ron

[fredrosse]

Stainless steel can take temperatures far above anything ordinary steels can. Wetted boiler pressure parts are all kept at relatively low temperatures, perhaps 10F - 50F above steam temperature, so temperature is not an issue here. Even the boiler pressure parts that are directly adjacent to an intense furnace fire will be kept to a relatively low temperature, provided the scale buildup on the waterside of the boiler is kept within reasonable control.

But in the high temperature furnace with parts that are not cooled by water, stainless will last far longer than ordinary steel, withstanding red heat continuously, vs. ordinary steel only holding up for days or weeks. That said, it is still better to keep the ash pan from getting too hot, so that the boat parts under the ash pan will not be heated. Insulation and air circulation under the ash pan is necessary to protect whatever is under the ash pan. If there is no insulation between the ash pan and the furnace, then the ash pan metal will get very hot, and as mentioned earlier, a layer of ashes in the in the ash pan is good insulation, and will keep ash pan temperatures down.