JUCA Built-In Fireplace Furnaces

pix of an F-9A Think of having a completely normal-looking built-in fireplace with all the atmosphere it offers; at the same time heating the entire house with wood! You can enjoy the fire through large normal fireplace glass doors while the F-9A heats the entire house! Since the huge firebox can take giant pieces of wood, you get long, even, constant heating just like with a regular furnace. You just don't have to pay for gas, oil, or electricity! And the unit price is only about $1,900!

The appearance is EXACTLY that of a regular fireplace with brass doors. There is a hidden 4" offset in front of the main body to allow space for full thickness facebrick to be the facing of the fireplace. This allows maximum flexibility for you in your choice of facing materials, including brick, stone, veneer brick, ceramic tile, marble, limestone, etc. The firebox floor is lined with castable firebrick. Our standard 465 cfm blower is automatic and very effective. Optional blowers are even stronger, to enable heating a whole house through a duct system. Blower is 115 volt. Normally, the blower is mounted hidden in the wall alongside the fireplace, but it can be remotely located in a basement or elsewhere.

For a better view of the JUCA F-9A

Gas Burning

When the JUCA F-9A is used with a 24" set of gas logs, the appearance is exactly that while using wood. The enjoyment of watching the flickering fire through the brass doors is wonderful. While this is happening, the 90,000 Btu/hr gas-log burner is creating enough heat, that is captured by the sophisticated JUCA heat exchanger system, to be heating the whole house! A variety of log styles are even available, from Mountain Oak to Twisted Cypress to White Birch. Various accessory control systems can use a wall thermostat to cycle the burner on and off like a gas furnace or be controlled by a handheld remote control. The automatic wall-thermostat controlled operation of the gas logs' fire cycling on and off is a popular option when burning gas, so that the JUCA fireplace can act as the house's central heating system!

It's great to have this mode of operation while gas prices are reasonable while still having the capability of heating the whole house with wood if something silly happens again in the Mideast. The change only takes a minute or two. The best of both worlds!

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A unique advantage of JUCA's non-airtight design is that, whether using wood as the fuel or gas logs, you can open the Bi-Fold Brass Doors to roast marshmallows. All the while, it's still heating the whole house! The JUCA F-9A still works extremely well, even with its doors open!

JUCA Model F-9A, showing features The rotating JUCA Model F-9A at left shows some of its features.

On the front is the large opening of the huge firebox (brass doors removed for clarity). The (included) door assembly has a draft control for air for the fire.

On one side of the body is the (Standard) blower ; on the opposite side is the 8" by 16" warm air outlet (to feed into ducts and/or to warm air registers in the room). An automatic blower control has a temperature probe in the warm air chamber there.

Notice the offset of the door assembly to the main body (we call it the "snout") that allows space for full thickness facebrick everywhere on the facing. Also note the heat baffle and air chambers below the firebox.

The entire firebox is surrounded by heat exchange chambers, to capture radiant heat from the fire inside. Not visible are the tubular heat exchangers bridging across inside above the fire, to capture convective heat from the smoke.

The JUCA F-9A Series is intended to allow maximum flexibility in accomplishing a desired appearance in an installation. If the homeowner wants a rugged fieldstone faced fireplace, an F-9A is perfect. If the desired appearance is that of an 18th Century Rumford traditional fireplace surrounded by an ornate mantel, the JUCA F-9A is again perfect. Ditto for a French Provincial treatment or a Hyper-Modern motif.

JUCA's desire to supply custom sized or styled units makes all this practical. YOU just specify the required width, height, or depth (if you feel our standard sized F-9A is inappropriate for your application.)

If you're the type considering a Hyper-Modern motif, you certainly must have liked the photo of our Wedge-Shaped Fireplace Door-Set. We truly are capable of creating virtually any appearance you need.

With a JUCA, you get remarkably even, comfortable, long lasting heat everywhere in your house. You can eliminate your regular heating fuel bill. It feels great to carry wood to your JUCA knowing that each armload saves you $3.00 or more on your heating bill. There are no cold drafts, even at floor level. The built-in computer-assisted-design heat exchanger is so efficient that you get more usable heat with less wood burned.

While heating fuel prices have been low, many people have bought JUCA F-9As and installed (automatic wall-thermostat controlled) gas logs. They can heat the house using our JUCA as a 140,000 Btu/hr gas furnace. (Gas log ratings often limit this to 90,000 Btu/hr, but that's still usually enough to entirely heat most houses.) When fuel prices go through the roof (and they will) it can easily be converted back to wood in under 2 minutes! The best of both worlds! You can't even tell the difference at the house's warm air registers when you change from one to the other. The F-9 has been safety tested and approved to UL Standards.

Model F-9A

The brass bifold doors make the appearance exactly like a regular built-in fireplace. The only difference is that it can heat the whole house with wood and eliminate your heating bill! And there are actually over 2,000 different appearances available! Including Arch-Top appearances which have been very popular in recent years.


If a utility room or garage is behind the fireplace, this option would allow you to be able to feed the fire from the back through a steel rear feed door (or the regular way from the room).


This is a double-sided fireplace version of the F-9A. If your application involves a see-through or back-to-back fireplaces, consider the X- option on a JUCA F-9A model. Normal thru-the-wall depth is 30" (but, as in everything else, we're flexible on it!)

You have a lot of input on such a unit. If you want one side to be an Arch-Top and the other (normal) Rectangular, and if you want it 27" deep, there's little or no extra charge!


Door Assembly appearance. We offer over 2,000 different door facing assemblies. Traditional framed or unframed clearview; antique or polished brass, black, copper, nickel, chrome, pewter, real marble, or combination finishes; plated finish or solid brass; bi-fold (4 panel) doors or cabinet-style twin doors; even arch-top designs; very plain to very ornate.


We consider the most popular size of fireplace in America, the so-called 36" by 28", to be our standard size. HOWEVER! We can easily adjust any of the dimensions to fit an application. Our normal firebox is 24" deep, much deeper than the common 16-18". (We like to be able to put HUGE amounts of wood inside! For people who want shallower fireboxes (we call them pancake units), there is no extra charge. Similarly, we normally put a 4" snout on the F-9A to provide for the thickness of regular facebrick. When people intend to face their unit with stones from their farm fields, we have made snouts as large as 10" deep. Veneer brick facing can allow snouts as small as 1" if space is tight and firebox depth is less important. (Nearly everyone gets the regular 4" snout.)

Width is also buyer selectable. For each 6" extra width over our regular width F-9A, add $250 (mostly for material.) We make quite a few 42", some 48", a few 54", and occasional units up to 78" wide. If you're going above 42" wide or you have a rather short chimney, use the Chimney Design Calculation Program to confirm appropriate chimney size and performance. Or check this guidance page.

Opening Height is also buyer selectable. If higher than the regular 28", then use (319) as above and contact us for price differential. Or check here.

Arch-Top units of ANY oversize should use (319) to make sure there is extra chimney capacity for that size unit. Or check here.


. F-9A F-9AX F-9AR
RatedOut(Btu/hr) 140,000 100,000 125,000
Log Length: 24 in 24 in 24 in
H/W/D (inches): 47x43x26 47x43x30 47x43x27
Flue Size: 10 in 10 in 10 in
Firebox: 12.3 cu ft 15.4 cu ft 12.3 cu ft
Firebox H/W/D: 26x34x24 26x34x30 26x34x24
Door Ass'y Size: 36" x 28" 36" x 28" 36" x 28"
Expcted BurnTime 10-11 hr 7-11 hr 10-11 hr
Blower (cfm): 465 to 2550 465 to 2550 465 to 2550
Duct Outlet: 8" x 16" 8" x 16" 8" x 16"
Weight: 635 lb 545 lb 655 lb
Price: $1,889

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