Help authenticating a Fisher Fireplace Insert

[Ormand]

Would verification of the dimensions of the materials of construction be a way to authenticate a Fisher Fireplace Insert?

Is another option to compare the clearances with those recommended in the Fisher owner's Manual?

Background
I need to authenticate a Fisher Fireplace Insert which a previous home owner claims is a genuine Fisher Stove purchased in Cranbrook BC in the 1990's. The internal dimensions of the stove are 20 inches front to back and 24 inches side to side. According to the dimensions appearing in the forum, it appears to be Grandma Bear although I suppose I would need to measure the internal height of the stove to confirm.

A WETT-certified inspector could not find any certification label and issued the following conclusion:
"The installation appears to be done well with the closest distance to combustibles in 16 inches to the wooden trim on the sides of the facia. However as there is no certification label on the unit I can not determine if that clearance is enough to safely operate the unit."

A further inspection by the local Acting Fire Chief.

I have posted a photo of the front elevation view for reference.

Thank you in advance for your assistance.

Yours truly,

Ormand

 

[coaly]

It is not an Insert, it is a pre-1980 Grandpa Bear with legs cut down to fit into hearth.

The Insert was designed in 1979 and used the Cathedral style arched top doors only. The doors were Grandma Bear doors. The Insert is flat on top with no step top. It has a secondary box welded over the inner firebox only on the back half. The outer shell has an opening like a slot under the ash fender for air intake that is exhausted at the top. Here is an Insert removed;

They are much deeper than a freestanding stove such as yours.

The old flat top doors are easy to tell what stove body they are on. Below is a Grandma (note how close space between trees is at door seam) and a Grandpa with much larger spacing that matches yours.

Grandma


Grandpa

Notice the comparison stoves pictured above have bent handles. Yours are longer and straight, indicating yours is a bit older than the later bent handles. I'd guess yours to be late '77 or early '78 with the older handles and newer 5 fin draft caps.

 

[Ormand]

It is not an Insert, it is a pre-1980 Grandpa Bear with legs cut down to fit into hearth.

The Insert was designed in 1979 and used the Cathedral style arched top doors only. The doors were Grandma Bear doors. The Insert is flat on top with no step top. It has a secondary box welded over the inner firebox only on the back half. The outer shell has an opening like a slot under the ash fender for air intake that is exhausted at the top. Here is an Insert removed;

View attachment 198136 They are much deeper than a freestanding stove such as yours.

The old flat top doors are easy to tell what stove body they are on. Below is a Grandma (note how close space between trees is at door seam) and a Grandpa with much larger spacing that matches yours.

View attachment 198138 Grandma


View attachment 198137 Grandpa

Notice the comparison stoves pictured above have bent handles. Yours are longer and straight, indicating yours is a bit older than the later bent handles. I'd guess yours to be late '77 or early '78 with the older handles and newer 5 fin draft caps.

Dear Coaly,

Thank you for your prompt reply and your invaluable assessment.

You have been most helpful.

I will forward this information and the Fisher Owner's Manual to the Inspector and request a reassessment of the installation.

With sincere appreciation, yours truly,

Ormand

 

[Ormand]

Dear Coaly,

Thank you for your prompt reply and your invaluable assessment.

You have been most helpful.

I will forward this information and the Fisher Owner's Manual to the Inspector and request a reassessment of the installation.

With sincere appreciation, yours truly,

Ormand

Hello Coaly.

We have not been able to find a certification label on the sides or back of the stove. Could it be on the bottom?

Ormand

 

[coaly]

As stated above, it is a pre 1980 Grandpa Bear with legs cut down. It is not a UL listed stove. (Listed Grandpa would have shields and baffle inside and not have angle iron legs) It would have a tag on the rear shield with new style arched type doors that were produced after 1980.
IF this were a listed appliance, it would loose its listing since the legs are shorter than the minimum 6 inch requirement for the testing. (listing)

Below is a Listed Grandpa Bear;

 

[Skip E]

Hi guys. I really don't know if I am posting this in the right spot or not. I am using my phone because I do not have a computer in my home.

Please let me know if I am suppose to post this somewhere else.

So I have been in my home for 3 years and love my woodstove but I'm not sure what model it is. We are trying to get more heat out of it this winter. I have taken the sides off to inspect it and see if I might be able to get feet for it or at least put it up on bricks.

Question 1,

Does anyone know what model fisher this stove is?

Question 2,

Can I get some feet to put under it?

Question 3,

What's the best way to get more heat out of this stove?

Question 4,

Does anyone know what this stuff is thst is on top of my stove and around the sides?

Thanks so much for all your help in advance

 

[begreen]

Does anyone know what this stuff is thst is on top of my stove and around the sides?

Is this stove connected to a full liner to the top or just stubbed up with a short pipe past the damper area? If it's the latter, that is a problem and would explain the junk that is sitting on top and around the stove. If that is the case it needs a full stainless liner to the top of the chimney. Stove pipe is not acceptable.

 

[Skip E]

It has a liner that goes all the way up to the toof the chimney.

Thank you for your reply.

 

[coaly]

First, it's an Insert, not stove. There are no feet used on an Insert.

There is a slot under the firebox that a blower connects to for more heat from the firebox.
There were also blowers available that hang on the front blowing into the side slots. Both styles blow the hot air out the top, which extracts much more heat from the exhaust area you can see through the slot.

Do you have the front cover plates? There must also be a deflector plate across the top to deflect heat from rising up the wall under a combustible mantle. (not shown in pictures)

The doors would be Series III if is is a full size Insert, (called Fisher Fireplace Insert with Glass and Brass) or Honey Bear if smaller.
Does it have an 8 inch outlet with door opening of 17 inches wide X 10 1/2 high?

I don't see a damper control that should be integral built into the Insert. Is there any damper in the outlet with a lever to close it??
If not, you need a damper, or preferably a baffle in the firebox.
The Baffle thread has all the info needed, but fabricating and adjusting depends on chimney flue diameter all the way up. Also is the flue liner insulated?

 

[Skip E]

First, it's an Insert, not stove. There are no feet used on an Insert.

There is a slot under the firebox that a blower connects to for more heat from the firebox.
There were also blowers available that hang on the front blowing into the side slots. Both styles blow the hot air out the top, which extracts much more heat from the exhaust area you can see through the slot.

Do you have the front cover plates? There must also be a deflector plate across the top to deflect heat from rising up the wall under a combustible mantle. (not shown in pictures)

The doors would be Series III if is is a full size Insert, (called Fisher Fireplace Insert with


Glass and Brass) or Honey Bear if smaller.
Does it have an 8 inch outlet with door opening of 17 inches wide X 10 1/2 high?

I don't see a damper control that should be integral built into the Insert. Is there any damper in the outlet with a lever to close it??
If not, you need a damper, or preferably a baffle in the firebox.
The Baffle thread has all the info needed, but fabricating and adjusting depends on chimney flue diameter all the way up. Also is the flue liner insulated?

Yes I do have both sides along with the top and the deflector plate.

I had to take the damper control handle off so I could take the covers off to clean behind the insert.

Yes it has a flue liner.

I have not had a chance to get measurements. I should be home tonight so I will get to them then.

I have been using the unit for 2 years now. I'm not real happy with the amount of heat we get from it. Is there a better option? Should I convert to a stove or a different insert? I may not know how to use it properly..... I think I am using it right but I wrong. I would really like to use this a the primary heat in my home.

Thank you coaly for your response and your help.

 

[coaly]

Without a blower you are only getting the heat that naturally convects off the back of it by rising through the upper front slot. The blower extracts heat from around the hottest area at the pipe outlet. That is the first improvement needed.

Measure the flue outlet and flue size at the top. Also see if the flue liner is insulted with a insulation wrap, or filled around it with some sort of material. If you are using an 8 inch liner with no insulation, the heat required to be left up the chimney is much greater than a downsized liner with insulation wrap to keep it hot inside with less heat loss from the Insert. Once I know the outlet diameter and flue height I can further advise on making it more efficient. Also is the chimney inside the home or exterior? Masonry?

Heat output starts with the efficiency of the chimney and flue. A 6 inch well insulated flue with a baffle in the appliance will give you much more usable BTU inside since very little heat is required to leave up the stack to make it go, compared to needing twice as much left up with an inefficient larger flue. Making the Insert work properly starts with the chimney. The damper operation is a controlled resistance to flow which changes velocity. Again, it controls the chimney, which affects the stoves oxygen input.

When you were using the Insert, were you starting it with side and front air intakes open, then closing the side intakes when up to temperature?
With a properly drafting chimney, you should be able to only open the air wash intakes for a normal burn. Only starting or extreme cold should require more oxygen from the side primary inlets. (A Insert or stove dumping into a large fireplace flue requires the side vents open for a much faster burn to allow more heat up to keep the larger area above 250* to the top) If your flue is insulated AND the correct size, you can then close the damper somewhat to control overdraft. If you have an uninsulated large 8 inch flue, you need to leave the flue damper open more to keep the flue above 250* to the top when smoke is present. That is the key to keeping the chimney clean. Allowing too much heat out decreases efficiency wasting heat up the stack. You may or may not be able to install a baffle depending on chimney type, flue height and diameter. The baffle adjustment is about the chimney, not the stove. In your case it becomes a bit more critical due to keeping glass clean.

 

[Skip E]

So you are right coaly, the door opening is 17" by 10-1/2"


My flue opening is 8" 20' tall uninsulated 8 inch liner.

The chimney is brick with the liner inside of it.

I would open everything up to start the stove and then close it off when it started burning good. I would close the damper when we would go to bed and leave the front open a little bit. Doing this would get us more heat then leaving it all closed tight but I would have to get up in the middle of the night to load it back up.

I do not have a baffle but can install one. I was reading up on them here. My insert it top vented to I would weld a 8" plate like I saw someone do on here.

Do I need to change out my lines for a 6" insulated liner? If so would a 316Ti stainless steel pre insulated chimney liner from rockford chimney supply be a good choice?

Thank you for your help coaly. You really seem to know your stuff.

 

[coaly]

OK, you have a full size Insert.
Legally you can only reduce 1 inch down to 7, but the firebox size is great for 6 inch. They were built to slide into the hearth and use the existing fireplace flue which would be much larger. So they were made with the oversize 8 inch to allow enough heat up a much larger flue. Now all Inserts must be direct connected to the flue and a 6 inch insulated liner gives you more draft with less heat lost up the smaller diameter. It has less capacity, but you rarely use them wide open needing the capacity of the 8 inch.
The damper is a variable resistance that slows velocity. In turn slowing the incoming air through intakes. A baffle adds resistance within the firebox slowing velocity, as well as allowing more smoke particles to burn. Less particles means less creosote at critical temperatures. The smaller diameter flue creates faster rising of gasses with less dwell time to stick.

The installation standard was written to prevent reducing a correctly sized connecting pipe and flue to the same size outlet, which is 6 inch on Papa Bear, which is larger than your firebox. Even with an internal baffle, there are no smoke roll-in issues with 6. You can always try a baffle with your existing flue and adjust the smoke space (the area smoke travels through above baffle) to 50 square inches. If you downsize to 6, raise it for 28.5 square inch opening. Duration of fire has a lot to do with fuel and coal pile built up from extended burning. You should have plenty of coals left in the morning to rake ahead and start the new fire. (this is a good time to remove some ash each morning from the front where it burns down to finer ash and rake some ash ahead with coals, preventing the need to let it go out for ash removal)
Close the primaries overnight and crack the fronts like you are when little heat is needed, open more for colder nights.

Do you have to clean more than mid season and end now? That is far from an optimal flue and is where a lot of heat is going. You'll see a drastic reduction in cleaning with an insulated flue.
Between that and a fan you won't need to get up to reload in the night unless you have a much larger space than the insert was designed for. (1750 - 2000 s.f. with average insulation back in 1980)