is it better to burn in a fireplace with or without a grate

[iceman]

woodstoves and insert don't use grates will you get a better burn without it
i was talking to a regency rep today and he said ash you should always keep a couple of inches of ash in a stove because it gives off more heat???????
i thought he was playing with me but he was serious is the joke on me?

 

[Corie]

You don't keep any ash on the floor of your stove? I don't know if it gives off more heat, but it does help hold a coal bed longer and gives better starts IMO.

 

[jpl1nh]

In my experience with a fireplace, a grate is important. However, a grate that doesn't sit very far off the hearth, say only an 1 1/2"-2" works better than one further up. I think a grate serves two purposes in a fireplace. Perhaps the most important is that it keeps your wood from rolling out of the fireplace! Second, it makes it easier to get air around your wood in the burn process. I agree with Corie about a stove, and the same is somewhat true in my experience in a fireplace, that being that some ash makes it easier to start the fire. That's why a good fireplace grate or end irons ar pretty low to the ground. But yup, a good wood burning technique is to keep a good bed of ash.

 

[webbie]

I think certain grates are better with a fireplace for these reasons:
1. An extra safety factor for downward radiation
2. Since a fireplace brings air into the entire opening, why should it go under some logs sitting on the floor bricks? - So by keeping it up on a grate, you are allowing combustion air to flow around the logs.

In terms of a stove, #1 also applies - the ash helps protect against radiation to the hearth - also helps cradle embers away from the air flow so that there are coals in in the morning.

All in all, it depends (as usual) on the exact unit and also the burning techniques. If you criss cross your logs in a fireplace correctly, you are essentially creating a temporary grate.

 

[BrotherBart]

I am no stove engineer but I know that every time I forget and clean all of the ash from my stove it takes forever to start it up and get it up to operating temp the next time.

 

[webbie]

You have a point, BB - that's why I said it varies - in cast iron stoves without liners and grates, an inch or two is nice. In certain steel models without a lot of room below the loading door - and with fireboxes that are larger in width then height, ash can be a pain.....

 

[jtp10181]

Simple Answer - if it is supposed to have a grate, use one. If its not, don't. They are engineered to either have or not have a grate, I don't doubt the engineers in that aspect of design.

 

[KeithO]

I'm prepared to bet that adding a layer of good alumina needled mat on top of the firebrick would provide all the benefit attributable to a layer of ash, while being much easier to maintain. It would basically be a highly insulating layer that would block heat transfer into the firebrick initially due to its low thermal conductivity and it would reflect most of the initial heat back at the logs to help get the fire started. Once the fire is going good the firebrick will warm up and get up to normal operating temperature as normal.

Without the ash, the absorbtion of heat from all the firebrick slows down the heating process and the cold smoky phase lasts that much longer.

 

[Harley]

You don't keep any ash on the floor of your stove? I don't know if it gives off more heat, but it does help hold a coal bed longer and gives better starts IMO.

Corie has the simple, concise answer answer for you there Ice (surprising for an engineer.... just kidding, Corie). Other than the "end of the season" cleanout I think it's always good to keep a good bed of ash in the stove. I think it does help in retaining some heat, by being able to uncover some nice coals in the morning that are all ready to burn and throw some wood onto the stove and get it up and going. The bed of ashes also does help with a "cold" start by letting some air around the kindling wood, and probably has some degree of insulation for the bottom of the stove to keep that from getting too hot.

 

[Hogwildz]

My manual for the Summit says to Keep at least 1" of ash on the floor of the Summit. And to empty some out when its about 3" thick.
I also read somewhere is helps insulate the firebricks & bottom of the stove. Maybe retains heat & coals for restarting? I dunno.