How to measure (60 seconds)
- Wall width: measure the finished wall area available (inches).
- Recess depth available: measure cavity depth behind drywall (inches) if recessed or partial recess.
- Install style: decide front-only, corner (2-sided), or 3-sided/bay (changes rough opening width).
- Power: plan a dedicated circuit; decide whether you want 120V (5,000 BTU) or 240V (10,000 BTU).
- TV above: confirm TV mounting height and follow TV manufacturer clearance guidance.
Clearance note
Keep furniture, drapes, bedding materials and all combustible materials at least 3 feet from the front of the fireplace. Keep combustibles away from the unit and follow all manufacturer and local code requirements.
Fit requirements table (hard constraints)
Rough opening dimensions below are the minimum per the instruction manual. The “Recessed framing / cutout” width shows fully recessed (single-sided) and 3-sided/bay options.
| Size | Model (SKU) | Viewing area (W×H) | Firebox (W×H×D) | Recessed framing / cutout (W×H×D) | Heat (standard) | Heat (optional) | Power + breaker | Link |
|---|---|---|---|---|---|---|---|---|
| 52" | OR52-MULTI | 50 1/8" W × 18 7/16" H | 51 1/2" W × 24 5/16" H × 9 9/16" D | 50 5/8" W (fully recessed) / 51" W (3-sided/bay) × 24 3/4" H × 9" D (min.) | 120V 5,000 BTU (supplemental) | Optional 240V hardwire, 10,000 BTU capable | Dedicated circuit required. For 10,000 BTU option: dedicated 20A (or higher) 2-pole breaker required (per manual). |
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| 60" | OR60-MULTI | 58 5/8" W × 18 7/16" H | 60" W × 24 5/16" H × 9 9/16" D | 59 1/8" W (fully recessed) / 59 1/2" W (3-sided/bay) × 24 3/4" H × 9" D (min.) | 120V 5,000 BTU (supplemental) | Optional 240V hardwire, 10,000 BTU capable | Dedicated circuit required. For 10,000 BTU option: dedicated 20A (or higher) 2-pole breaker required (per manual). |
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| 76" | OR76-MULTI | 74 7/16" W × 18 7/16" H | 75 3/4" W × 24 5/16" H × 9 9/16" D | 74 15/16" W (fully recessed) / 75 1/4" W (3-sided/bay) × 24 3/4" H × 9" D (min.) | 120V 5,000 BTU (supplemental) | Optional 240V hardwire, 10,000 BTU capable | Dedicated circuit required. For 10,000 BTU option: dedicated 20A (or higher) 2-pole breaker required (per manual). |
View on product page |
| 100" | OR100-MULTI | 98 3/4" W × 18 7/16" H | 100" W × 24 5/16" H × 9 9/16" D | 99 1/4" W (fully recessed) / 99 1/2" W (3-sided/bay) × 24 3/4" H × 9" D (min.) | 120V 5,000 BTU (supplemental) | Optional 240V hardwire, 10,000 BTU capable | Dedicated circuit required. For 10,000 BTU option: dedicated 20A (or higher) 2-pole breaker required (per manual). |
View on product page |
| 120" | OR120-MULTI | 123" W × 18 7/16" H | 124 3/8" W × 24 5/16" H × 9 9/16" D | 123 1/2" W (fully recessed) / 124" W (3-sided/bay) × 24 3/4" H × 9" D (min.) | 120V 5,000 BTU (supplemental) | Optional 240V hardwire, 10,000 BTU capable | Dedicated circuit required. For 10,000 BTU option: dedicated 20A (or higher) 2-pole breaker required (per manual). |
View on product page |
Installation type selector
Pick your install type to see the right constraints and wiring notes.
Built-in recess: rough opening (single-sided vs 3-sided/bay)
Use the “Recessed framing / cutout” dimensions in the table. For 3-sided/bay installs, use the larger width noted in the same row.
Wiring: Hardwire to a dedicated circuit. For the 240V / 10,000 BTU configuration, a dedicated 20A (or higher) 2-pole breaker is required (per manual). Do not exceed 80% of breaker load.
Partial recess: shallow wall depth setup
Partial recess reduces required cavity depth but the unit will project outward. Use these minimum partial-recess opening requirements: Height: 24 9/16" (all sizes) • Depth: 2 5/8" min.
Partial recess opening widths (A): 52" = 50 15/16" • 60" = 59 7/16" • 76" = 75 3/16" • 100" = 99 1/2" • 120" = 123 13/16"
Wiring: A dedicated circuit is required. For the 240V / 10,000 BTU configuration, a dedicated 20A (or higher) 2-pole breaker is required (per manual).
Wall-mount notes
Follow the wall mounting instructions in the manual (stud anchoring and bracket requirements). Ensure safety and heat protection by following the TV manufacturer’s clearance requirements rather than estimating distances.
Wiring: A dedicated circuit is required. For the 240V / 10,000 BTU configuration, a dedicated 20A (or higher) 2-pole breaker is required (per manual).
Size-by-size guidance (recommendations)
The Orion Multi series combines HelioVision flame visuals with a deeper firebox and multi-sided install flexibility (front-only, corner, or 3-sided/bay). Use the fit table above as the source of truth for opening sizes.
52" model
OR52-MULTI
Best for: Smaller media walls, bedrooms, or corner installations in compact living areas.
Why: This is the most popular size for standard 2×4 or 2×6 wall build-outs. It’s an ideal choice for a 3-sided “Bay” installation when you want multi-angle viewing in a smaller room.
Viewing area: 50 1/8" W × 18 7/16" H
Recessed cutout: 50 5/8" W (fully recessed) / 51" W (3-sided/bay) × 24 3/4" H × 9" D (min.)
Firebox: 51 1/2" W × 24 5/16" H × 9 9/16" D
60" model
OR60-MULTI
Best for: Standard living rooms and mounting beneath 65" televisions.
Why: The 60-inch model provides a strong 1:1 visual balance with most mid-to-large TVs. With an 18" tall viewing window, it feels more architectural than ultra-thin linear fireplaces.
Viewing area: 58 5/8" W × 18 7/16" H
Recessed cutout: 59 1/8" W (fully recessed) / 59 1/2" W (3-sided/bay) × 24 3/4" H × 9" D (min.)
Firebox: 60" W × 24 5/16" H × 9 9/16" D
76" model
OR76-MULTI
Best for: Large family rooms, basement retreats, and primary suites.
Why: Designed for wide feature walls, this size is ideal as a 3-sided room divider or a massive focal point in open-concept layouts—without the extreme length of 100"+ models.
Viewing area: 74 7/16" W × 18 7/16" H
Recessed cutout: 74 15/16" W (fully recessed) / 75 1/4" W (3-sided/bay) × 24 3/4" H × 9" D (min.)
Firebox: 75 3/4" W × 24 5/16" H × 9 9/16" D
100" model
OR100-MULTI
Best for: Expansive great rooms, luxury home theaters, and commercial feature walls.
Why: A true “statement” fireplace for high-ceiling rooms where smaller units can get visually lost. Its 10,000 BTU capability (when wired to 240V) can provide meaningful supplemental warmth for larger spaces.
Viewing area: 98 3/4" W × 18 7/16" H
Recessed cutout: 99 1/4" W (fully recessed) / 99 1/2" W (3-sided/bay) × 24 3/4" H × 9" D (min.)
Firebox: 100" W × 24 5/16" H × 9 9/16" D
120" model
OR120-MULTI
Best for: Grand-scale residential estates, hotel lobbies, and high-end restaurants.
Why: Stretching 10 feet in width, the 120-inch delivers a panoramic HelioVision flame experience built for world-class feature walls in the most expansive environments.
Viewing area: 123" W × 18 7/16" H
Recessed cutout: 123 1/2" W (fully recessed) / 124" W (3-sided/bay) × 24 3/4" H × 9" D (min.)
Firebox: 124 3/8" W × 24 5/16" H × 9 9/16" D
View product page and availability
Check current stock, select a size, and see current pricing on the main product page.
Safety and electrical notes are summarized from the Modern Flames Orion Multi instruction manual and Orion brochure. Always follow the manufacturer installation instructions and local electrical code. Use a qualified electrician for hardwire installation and any 240V / 10,000 BTU configuration.