

The Montigo P42DF is a 42-inch single-sided direct-vent gas fireplace with frameless glass — nothing bordering the flame: 32,000 BTU/hr on natural gas or propane, a 39-1/2" x 20-3/8" viewing area, a 42" W x 42" H x 21-7/8" D framed opening, $6,969, and a 15-year parts warranty on the firebox and burner. It is the Full Load tier — RX200 remote, variable-speed fans, black porcelain liner, halogen uplighting, and battery backup are all standard.
Choose it if the 38 reads small on your wall and the 52 reads like a commitment. This is the size most rooms actually want, with nothing left on the options sheet: concealed burner with Quartz firebeads, frameless glass, six remote-controlled flame levels and fan speeds, Smart Thermostat mode, and zero-clearance framing at the back, sides, and floor.
It is not right if you plan to vent propane straight out the back wall — straight-through rear venting is natural-gas only; if you want the fireplace recessed into an existing wall cavity (prohibited); if your wall cannot give up 21-7/8 in. of depth; or if you need home-automation integration, which Montigo's control system does not support.
Frame a rough opening 42 in. wide, 42 in. tall, and 21-7/8 in. deep. Clearance to combustibles is zero at the back, sides, and floor; keep 17-1/2 in. above the unit on a top-vent install (9 in. rear-vent) and leave the supplied 7-1/2 in. standoffs in place. It runs on natural gas (5.5 in. w.c. minimum inlet pressure) or propane (11 in. w.c.) by variant, lights with SIT Proflame 2 electronic ignition, and needs unswitched 120 VAC, 60 Hz power at 6 amps. Efficiency (P.4.1-15) is 57% on natural gas and 60% on propane.
The P42DF sits in the middle of the single-sided line. The P38DF ($6,249) drops to 25,000 BTU/hr in a 37-3/4-inch opening; the P52DF ($7,849) jumps to 40,000 BTU/hr, a 47-inch view, and larger 5/10 venting. Same size, lower price: the Basic-tier PL42DF ($5,109) keeps the 32,000 BTU/hr natural-gas rating, framing, and venting but makes the remote, fans, liner, and battery backup optional — with no uplighting or WiFi offered at all. For a two-room flame, the see-through L42FSD (from $7,059) shows a 39-1/2" x 20-5/16" view on each side.
Vent pipe is sold separately and sized to your layout. The P42DF uses 5 in. inner / 8 in. outer coaxial direct vent and ships set up for top venting; it can be converted to rear vent. Straight-through-the-wall rear venting is approved on natural gas only (up to 12 in. of horizontal with no vertical rise). Top-vent wall terminations need at least 40-1/2 in. of vertical rise on natural gas (53 in. on propane); horizontal runs can reach 15 ft with 9 ft of vertical on NG (10 ft on LP), and roof terminations can run up to 32 ft above the fireplace. Beyond Montigo pipe, the manual approves DuraVent 58DVA-series, ICC, MetalFab, Selkirk, and Flexmaster components — The Torch Guys stocks compatible DuraVent.
Yes. Ignition is SIT Proflame 2 electronic (120 V), and the Full Load includes the AF40BP battery backup tray as standard — four AA batteries keep ignition working through an outage. The blower fans run on household power, so plan on radiant heat only until power returns.
It is certified as an indoor gas fireplace (CSA/ANSI Z21.88-2019 / CSA 2.33-2019). Montigo does permit single-sided Phenom models in protected outdoor locations, with conditions: the space must be sheltered from direct water, the overhang must extend at least 75% of the fireplace's height dimension across the front and both sides, every indoor clearance still applies, and the supplied safety screen must be used. Never operate it below 32°F. The fireplace cannot penetrate the building envelope and cannot be recessed into a wall cavity.
The Full Load ships with the SIT RX200 multi-function remote: on/off, six flame levels, six fan speeds, thermostat and Smart Thermostat modes, and a key lock. Optional SIT-WIFI phone app control is available for Full Load units. One honest caveat straight from the manual: the control system "Can not be used with home automation systems" — so no Alexa, Google Home, or Control4 integration.
It matters where you buy. Montigo's residential warranty is not applicable to equipment sold direct to consumer through internet or auction sites that are not authorized dealers. The Torch Guys is 1 of only 3 authorized Montigo e-commerce dealers in the United States, so buying here keeps your coverage intact: 15 years parts on the firebox, heat exchanger, and main burner (1 year labor), 15 years on Montigo venting, 10 years on Montigo terminations, and 1 year on most other components. Montigo requires licensed professional installation and annual service to maintain coverage. If you ever need a claim, we file it with Montigo on your behalf — call us at (410) 324-6322.