Dimplex Opti-Myst 66" Linear Electric Fireplace

The Dimplex Opti-Myst 66" Linear Electric Fireplace (model OLF66-AM, Dimplex order number X-136793) does not imitate fire with light alone. It boils nothing and burns nothing — ultrasonic transducers atomise water into an ultra-fine mist, and multicolour LEDs light that mist from below. What rises off the log set is real, three-dimensional vapour that behaves like smoke, because it is behaving like smoke.

The practical consequence is that the flame produces no heat at all. The glass stays cool to the touch, and the flame effect and the heater are completely independent — run the fire on its own through a July evening, or switch the heater in when you want it. At 66" this is the middle of the three sizes, and the one that suits a standard great-room wall without dominating it.

Key Features

• Opti-Myst® Vapour Flame
  Patented ultrasonic technology produces water vapour that reads as both flame and smoke. Because the flames generate no heat, the glass is cool to touch.
• Multicolour LED Flame
  Individual lights can be controlled and mixed. Choose a traditional amber glow, a contemporary colour, or set the range to rotate automatically.
• Adjustable Spacers
  Spacers and slots let you shape the flame width and profile, so no two installations look quite the same.
• Crackling Sound Effect
  Built-in crackle at your chosen volume, or off entirely.
• Flame Connect App
  Wi-Fi enabled. Adjust flame intensity, colour, heater and sound from your phone. A handheld remote is included as well.
• Continuous Water Supply
  Hard-plumb it and it never needs filling, or use the refillable container for up to 6 hours of flame per fill.
• Sealed Glass Insert
  Fully self-contained, so drafts cannot disturb the flame.
• No Venting Required
  No chimney, no gas line, no flue. Emissions are water vapour.

Will It Fit? Rough Opening

This line needs two openings measured, and they are not the same number. The framing carries the appliance; the finished drywall opening is the smaller aperture your finish material returns to.

Note the depth: 12" of framing. This is a deep appliance — it carries a water reservoir, a mist chamber and a heater — so it will not go into a 2x4 wall. Plan a bump-out, a chase or a masonry surround.

Water Supply — Plan This Before You Frame

The flame is made of water, so the unit needs a supply of it. There are two ways, and the decision has to be made before the wall closes:

• Hard-plumbed (recommended). A 1/4" copper line via the CDFIPLUMB-KIT, which we stock. The fireplace then runs indefinitely with no intervention.
• Refillable container. Part 9601350100RP. One refill gives up to 6 hours of flame, so this suits occasional use rather than a fireplace you run every evening.

Normal tap water is acceptable. In hard-water areas Dimplex recommends a water softener, and unfiltered water from a well or other unmonitored supply is not recommended. An in-line mesh filter is included, and an overflow sensor shuts the unit down if the level runs high.

Fresh Air Inlet — Required, Not Optional

This is the single most-missed requirement on the Opti-Myst Linear, and it is the one that causes warranty calls. The enclosure must be ventilated:

Dimplex's guide is blunt about it: "Failure to include a fresh air inlet will result in poor flame performance and damage to the fireplace." If your design seals the appliance into an airtight cavity, it will not work properly and the damage will not be covered. Call us and we will work through the detail with your installer.

Electrical Requirements

A word on that 12.3 A. On 120 V this model draws 12.3 A, which on a 15 A circuit leaves very little headroom — it needs a dedicated circuit, not a shared one, and it is the reason we push customers toward the 240 V wiring where the run allows it. At 240 V the draw falls to 9.0 A while the input rises to 2,180 W, so you get more heat on a lighter current. We stock the OLFPLUG cord kit if you would rather plug it in than hardwire, but note it is 120 V only.

On BTU figures. Dimplex publishes no BTU rating for the Opti-Myst Linear, and we have chosen not to invent one by converting the wattage. On this line the rated input also runs the ultrasonic transducers, the fans and the LEDs, so watts do not convert cleanly into delivered heat — the 86" model proves the point, drawing 1,020 W at 120 V while producing no heat whatsoever. Treat the Opti-Myst as a supplemental heater bought for its flame, and size your primary heat separately.

Location

This is an indoor appliance. Dimplex's installation guide states plainly: "Do not use this fireplace outdoors." Unlike the IgniteXL and Ignite Evolve lines, there is no covered-outdoor certification for Opti-Myst — the water system rules it out.

Specifications

Documents & Downloads

• Technical Specifications — OLF66-AM
• Installation and User's Guide (7216400100R02) — OLF46 / OLF66 / OLF86-AM
• Dimplex 2026 Electric Fireplace Collection

Warranty

2 YEAR LIMITED WARRANTY. Dimplex's current specification sheet for this model states a 2-year limited warranty on electrical components, running from the date of first purchase. Download the full Dimplex warranty. Note that Dimplex excludes Hawaii, Alaska, Yukon, Nunavut and the Northwest Territories from warranty coverage. The installation guide packed with the unit also refers to a longer term on materials and workmanship; if that distinction matters to your purchase, call us and we will get it confirmed in writing from Dimplex before you order.