Where do I put the grate?

[robynnc]

hi, this seems like a silly question but it is vexing us a lot. About 3 years ago, we took out an old insert in our fire place. It had the forced air fan that blew warm air out in the room. Or did at one point as what we discovered were holes in the tubes so what it really blew out in the room was bits of embers, ash, etc. Since flaming cat was not the goal, we took it out. Now the problem.

We got a generic fireplace grate to put the wood on. Where ever we put it in the fireplace, it smokes us out of the room. Is there some formula or guidance you can give for how far between the front & back of the fireplace the grate should go so that the draw works and sends the smoke up the chimney. It seems we have tried all the way back, as far forward as seems comfortable and everywhere in the middle but still, we're getting smoked!

Thanks for your advice. I appreciate your time.
Robynn

 

[Corie]

I have a feeling the smoke in the room has little or nothing to do with the grate you're using. Chances are the reason the insert was put in the first place is because the chimney probably wasn't made properly and thus doesn't draft correctly.

I would have the chimney and fireplace system inspected before going any further. For all you know the entire fireplace system is poorly or unsafely built.

 

[robynnc]

We had the chimney cleaned & inspected. The guy told us everything looked fine, suggested that we put caps on the chimney which we did. We have since removed the caps as thought they were causing the problem.

It seems to me like the grate is either too small for the fireplace, or we put it too far back. I was looking for some sort of diagram for how the currents work that make it draw and to figure out what the proportions are supposed to be for sizing a grate but could not find that sort of resource.

Appreciating your ideas, thanks.
Robynn

 

[recppd]

Just curious if you're looking for heat or ambiance. Because you won't get heat from just the fireplace.

Was there a liner installed on the old insert? If so, did you remove it? Was there a block off plate? If so, did you remove it? Can you give any more details or pics of what the damper looks like?

 

[robynnc]

It's ambience. I live in Seattle. While right now it's cold here, we don't get *real cold* here. I grew up in New England & moved away from *real cold*!

We took out all the parts of the insert. Once it was gone, there was bare brick in the fire place, and flat floor that had nothing to prevent any thing from going in our out of the fireplace. The new doors have a frame on all sides, a couple inches wide and bi-fold doors.

We don't have exhaust fans running when we start the fire, or running much besides. The houses out here are not what one would call air tight, but I don't think the out draft is that strong.

What makes me think it has something to do with where the grate is located is that we used the old insert for 2 years without running the fan. In fact, the fan box had been removed so that it could not be turned on accidently We did not have the smoke problem then. I know the fire/logs, etc were higher from the floor of the fire place when the insert was there as is had those bulky pipes that raised everything up, and still had space for ash/embers below. I just can't figure out where the grate part of the insert was in relation to the opening, back wall, etc.

The damper about mantle height in the chimney and is a plate that goes up when opened, or at least that is what it looks like to me from my point below it.

Robynn

 

[citizanken]

Robynn was the old insert attached to a chimney liner? was this removed also? If the old insert used a smaller diameter liner than your flue, it may have drafted better than an open fireplace.

 

[recppd]

If the chimney has no blockage, and the damper is open and unobstructed, then I would have to say it was a negative pressure issue. Living in Seattle, with all the rain and mild temps, it's quite possible you're dealing with barometric issues as well. It's definately NOT a "grate" problem.

Just out of curiosity, have you tried burning a Duraflame log? If so, are you having any smoke issues? If not, you may want to try one, just to see how it drafts.

 

[robynnc]

Wow, you guys know a lot about fire pleases.

There was no liner that I know about. Wouldn't that have interfered with the flue? When I look up the chimney, it is square and appears even up to the top. It looks like brick, I don't see anything added on.

And no firebox in the floor for cleaning out.

Here's kind of a picture, plain text of what it looks like.


| |
| |
| flue |
| |
| |
/ |
/ |
/ |
/ |
/
/
/
/
/ /
/ --------/
/__|__|___

Should there be that much space (my drawing is actually pretty accurate for scale) in front of the grate?
Should there be more behind?
There is about 8" clearance on both sides of the grate to the side wall of the box.
The fire place doors have a chain curtain and we close it when we attempt to have a fire but end up just shutting the doors and waiting for it to die out and the smoke to clear.

Thanks so much!
Robynn

 

[robynnc]

OK, so plain text does not work here...
I'll figure something else out...

 

[robynnc]

I have not tried the duraflame log. We'll try it and see what happens.

 

[Willhound]

Hi Robynn and welcome.
Just to be clear, the question you asked, and some of the suggestions that you are getting are like apples and oranges. Placement of a grate, or even the size, or even not using one, in my opinion has little or no effect on the issue you are describing. What most of the suggestions have been hinting around is that for whatever reason you seem to be suffering from poor draft up your flue. This can be caused by many reasons as pointed out, i.e. a dirty chimney, obstruction in the flue, an incorrectly sized flue, negative air pressure in the house, downdraft from wind and weather, etc.

A relatively safe and easy way to check draft is with a stick of incense. Light it up and move it in and about the opening of the fireplace, up closer to the flue, with fireplace doors open and closed (with incense inside of course), turn various exaust fans on and off, open and close doors, windows etc. This will show you exactly how the air, and consequently the smoke is moving in and out of your fireplace. This might then give you a better idea of what is happening and how to correct it. Maybe a little safer and easier than a duraflame log too. That way if you have a problem you don't have a full duraflame log to contend with, and you can't move the log around like you can the incense.

 

[recppd]

If you had to guestimate the size of your flue, how big is it (L x W in inches)? How tall is your chimney? And what floor is the fireplace on?

Is it any better when you open a window while the fire is burning? Have you ever gotten a fire started and drafting properly without the insert?

 

[Willhound]

Just to be clear, the question you asked, and some of the suggestions that you are getting are like apples and oranges.

WADR, I gotta believe there's a more accurate expression than "apples and oranges" to describe the analytical appraisal of the situation to which some of us are applying ourselves.

Ya, probabley. Too tired right now to come up with any though. :roll:

 

[elkimmeg]

Two other things try wrap up news paper like a tourch light it and hold it near the top of your opening this will prime the draft then crack a window w a bit while startup theat will help relieve the pressurization differencial

 

[Hogwildz]

yet another double post, sorry all.

 

[Hogwildz]

I am no pro by any stretch, and agree with Elk.
I have read about downdrafts with cold chimneys. Is the chimney on an outside wall of the house by chance?
I read similar to Elks technique, accept it was suggested to crinkle up a pc of news paper, lay it in or lightly wedge it in damper area. light it, the heat will cause the draft to correct itself upward and suck the burning paper up the chimney. If that works, set you kindling up read to be started and burned, set another pc of newspaper in damper area, light it, and when up draft it achieved, start the kindling while the updraft is going. Just my 2 cents.