Osburn 3500 Wood Insert
The Osburn 3500 Wood Insert combines power, efficiency and safety. At 110,000 BTU/h from a 3.5 cubic foot firebox it is the largest insert Osburn builds, rated for 1,000 to 2,700 square feet with a 10-hour maximum burn time, and its sober lines give way to one of the largest glass surfaces in its category.
Its flawless design reveals all the Canadian know-how in terms of alternative heating and will quickly become the house favorite. No harsh winter can resist it!
Because each house is unique, choose the door overlay, the faceplate and the trims that suit you!
Features
- Blower included, up to 144 CFM
- Heats 1,000 to 2,700 sq ft with up to 110,000 BTU/h
- 3.5 cu ft firebox that takes logs up to 22"
- Maximum burn time of 10 hours
- EPA 2020 approved, non-catalytic, 1.6 g/h average particulate emissions
- Ceramic glass door with cast iron frame and glass air-wash system
- Firebox lined with refractory bricks for better heat distribution
- Stainless-steel secondary-air system
- 3/16" steel body and 5/16" steel top
- Limited lifetime warranty
Will It Fit?
Measure your existing masonry fireplace opening before ordering. The 3500 Wood Insert needs at least:
| Minimum fireplace opening height |
26 1/4" |
| Minimum fireplace opening width |
31" |
| Minimum fireplace opening depth |
18 3/8" |
| Fireplace type |
Masonry only — factory-built fireplaces are not permitted |
| Chimney liner |
6" listed liner required, minimum 12' height |
Note that this insert is 29" deep overall against an 18 3/8" minimum opening depth, so a good part of the body sits forward of the hearth — check your mantel and surround clearances as well as the opening.
What to Order With It
The 3500 Wood Insert needs a door overlay, a faceplate and faceplate trims to be complete. Choose from each required group below.
Required – door overlay (choose one):
Required – faceplate (choose one):
Required – faceplate trims, same size as the faceplate (choose one):
Optional:
Performance
| Maximum heat output (dry cordwood) |
110,000 BTU/h (32.2 kW) |
| Overall heat output range |
17,200 – 57,800 BTU/h (5.0 – 16.9 kW) |
| Recommended heating area |
1,000 – 2,700 sq ft (93 – 251 m²) |
| Average overall efficiency (HHV) |
71% |
| Average overall efficiency (LHV) |
76% |
| Optimum overall efficiency |
77% |
| Average particulate emissions |
1.6 g/h (EPA / CSA B415.1-10) |
| Average carbon monoxide |
73 g/h |
| Maximum burn time |
10 hours |
| Overall firebox volume |
3.5 cu ft (0.099 m³) |
| EPA loading volume |
2.88 cu ft (0.082 m³) |
| Recommended log length |
16" (406 mm), loaded east-west |
| Blower |
Included, up to 144 CFM |
Specifications
| Combustion technology |
Non-catalytic |
| High-efficiency certified appliance |
Yes, EPA 2020 approved |
| Fuel type |
Dry cordwood |
| Maximum log length |
22" |
| Log positioning |
Loading over width and over depth |
| Chimney diameter |
6" |
| Flue outlet diameter |
6" |
| Type of chimney |
Liner - UL1777 |
| Minimum liner height (feet) |
12' |
| Baffle type |
C-Cast or equivalent |
| Approved for an alcove installation |
Not applicable |
| Approved for a mobile home installation |
No |
| Fireplace type |
Masonry only |
| Shipping Weight |
540 lb (245 kg) |
| Door type |
Single, glass with cast iron frame |
| Glass type |
Ceramic glass |
| Glass surface – dimensions (Width X Height) |
18 7/8" X 11 3/4" |
| Glass air-wash system |
Yes |
| Premium quality blower included (CFM) |
144 |
| Overall dimension (Height) |
24 7/8" |
| Overall dimension (Width) |
30 3/8" |
| Overall dimension (Depth) |
29" |
| Door opening – dimension (Height) |
9 7/8" |
| Door opening - dimension (Width) |
19" |
| Firebox – dimension (Height) |
12 7/8" |
| Firebox – dimension (Width) |
22 7/8" |
| Firebox – dimension (Depth) |
20 1/8" |
| Fireplace opening – minimum (Height) |
26 1/4" |
| Fireplace opening – minimum (Width) |
31" |
| Fireplace opening – minimum (Depth) |
18 3/8" |
| Firebox lined with refractory bricks for better heat distribution |
Yes |
| Stainless-steel secondary-air system improving gas combustion |
Yes |
| Steel thickness – body |
3/16" |
| Steel thickness – top |
5/16" |
| USA standard (emissions) |
EPA |
| USA standard (safety) |
UL 1482, UL 737 |
| Tested and listed as per applicable standards |
By an accredited laboratory |
| Warranty |
Limited lifetime |
Manuals/Documents
