Short answer: A water vapor fireplace makes its flame from a fine cool mist lit by LEDs, so the fire has real depth and movement and nothing burns. In return it needs water, an air intake and regular cleaning that an LED fireplace does not. Some Dimplex Opti-Myst models heat a room and some produce no usable heat at all. Check that before anything else.
How a water vapor fireplace works
An ultrasonic transducer sits in a small sump of water and vibrates fast enough to turn the water into mist. A fan lifts the mist through a slot in the fuel bed, and coloured LEDs light it from below. The result looks like flame and smoke, and it is cool to the touch.
Two things follow from that design. The fireplace uses water continuously while the flame is on, and the parts that touch water need cleaning. Both are covered below, with figures from the Dimplex manuals.
On the Opti-Myst Linear there is a three-minute warm-up before the flame starts, and Dimplex says to allow 10 to 15 minutes for the flame height to settle.
Which Opti-Myst models heat, and what each one needs
| Model | Heat | Water | Power | Price from |
|---|---|---|---|---|
| Opti-Myst Linear 46 | Yes | Designed for a plumbed 1/4 in. line | 120 V or 240 V, direct wire. 520 W flame only, 1,220 W or 1,920 W with heat | $6,349.99 |
| Opti-Myst Linear 66 | Yes | Designed for a plumbed 1/4 in. line | 120 V or 240 V, direct wire. 760 W flame only, 1,480 W or 2,180 W with heat | $8,729.99 |
| Opti-Myst Linear 86 | Only on 240 V | Designed for a plumbed 1/4 in. line | 120 V (1,020 W, no heat) or 240 V (2,400 W), direct wire | $9,749.99 |
| e-MatriX, one to three sided | No usable heat | Plumbed line required | 120 V, 270 W, direct wire | $7,034.99 |
| Opti-Myst Pro 500 RGB cassette | No heater | Refill container, or optional plumbed line | 120 V, 230 W, direct wire or optional plug kit | $2,299.99 |
| Opti-Myst Revive | Yes | Refill by hand | 120 V, 1,250 W, power cord or direct wire | $2,149.99 |
| Opti-Myst Aura | Yes | Refill by hand | 120 V, 1,275 W, power cord or direct wire | $4,199.99 |
Electrical and water details from the Dimplex and Faber installation manuals for each model. Prices as of October 2026.
Three rows in that table catch buyers out:
- The Linear 86 gives no heat on 120 V. The manual says the heat controls still respond, but only the fans run. If you want heat from the 86, plan a 240 V circuit.
- The e-MatriX is a flame-only fireplace. Its manual says the heat output is minimal and should not be treated as supplemental heat.
- The cassette is a module, not a finished fireplace. You build it into millwork or a custom surround, and it has no heater.
Water: tap, filtered, plumbed or filled by hand
What kind of water
For the Opti-Myst Linear, Dimplex says normal tap water can be used. In hard-water areas it recommends a water softener and warns that cleaning will be needed more often. It does not recommend unfiltered well water. The Linear ships with an in-line mesh filter.
The Revive and Aura manuals are less consistent. One page says clean tap water and another says filtered or decalcified water only. Use filtered water in those two and you satisfy both.
Plumbed or refilled
The Linear is designed to be hard-plumbed to a cold-water line with standard 1/4 in. tubing, with a shut-off you can reach for maintenance. If a water line is impossible, it can run on Opti-Myst refill containers, one per flame module. Dimplex says a refill gives up to six hours of flame and that this is not recommended for frequent use, because the front glass and media tray come off every time you refill.
The e-MatriX has no refill option. It needs a plumbed line, and its manual lists consumption at 0.30 litres an hour.
The cassette comes with a 42 oz (1.25 L) refill container and can be plumbed instead. The Revive and Aura are filled by hand.
Plumbing connections have to meet your local plumbing code, so a licensed plumber should make them.
The air intake nobody plans for
Every one of these fireplaces needs fresh air reaching the underside of the unit. Without it the flame is weak, and Dimplex warns that the fireplace can be damaged. For the Linear the required open area is:
| Model | Air inlet area | Minimum framing, W x H x D |
|---|---|---|
| Linear 46 | 80 sq in. | 48 x 31 3/4 x 12 in. |
| Linear 66 | 120 sq in. | 68 x 31 3/4 x 12 in. |
| Linear 86 | 160 sq in. | 88 x 31 3/4 x 12 in. |
If a grille covers the inlet, the opening has to be larger to make up for the area the grille blocks. The cassette needs 40 sq in. The e-MatriX, Revive and Aura each have their own inlet requirement in the installation guide. Ask us for the guide before you frame, and build from the manual that ships with your unit.
Cleaning and the transducer
This is where a water vapor fireplace differs most from an LED one.
- Linear, cassette, Revive and Aura: Dimplex requires the top cover, sump, any refill container and the transducers to be washed with soap and water at least once a month, and more often with poor water. The air filters rinse clean. Plastic parts do not go in the dishwasher.
- e-MatriX in a home: clean the sump and air filter every 12 months, clean the mesh filter every three months, and replace the in-line filter every 24 months. Commercial use has shorter intervals.
- Revive, Aura and the standard cassette: if the fireplace will sit unused for more than two weeks, drain it and dry the parts that hold water.
The transducer is a wear part. Owner forums, mostly about older UK stove models, have plenty of posts about transducers losing output and being replaced. Dimplex treats it the same way. The Linear ships with spare transducers in the box (two, three or four, depending on size), and the manual says to replace one when cleaning no longer restores the mist. The e-MatriX manual sets a schedule: replace the transducers every 12 months in a home.
None of this is difficult. It is a recurring job, and it is worth knowing about before you buy.
Who should choose water vapor, and who should skip it
It suits you if the fireplace is the centrepiece of the room, you want a flame with real depth that is cool to the touch, a cold-water line can reach the wall, and you or your building staff will keep up the cleaning.
Choose an LED fireplace instead if you want the least upkeep, there is no practical way to bring water to the wall, your water is hard and you do not plan to soften or filter it, or heat is the main reason you are buying. The Dimplex Ignite XL is the low-maintenance alternative, and our guide to the three Ignite linear series compares the options.
Which Opti-Myst model fits which project
- A long feature wall: the Opti-Myst Linear in 46, 66 or 86 in. It is the only linear model here with a heater.
- A corner, room divider or peninsula: the e-MatriX, in single-sided, two-sided or three-sided glass. No heat.
- Custom millwork, a bar front or an island: the Pro 500 RGB cassette, built into your own surround.
- A smaller room: the Revive or Aura, which have a heater and are filled by hand.
See the full Dimplex Opti-Myst collection.
Frequently asked questions
Do water vapor fireplaces give off heat?
The mist itself is cool. Heat comes from a separate electric heater, and only some models have one. In this range the Linear, Revive and Aura heat. The e-MatriX and the cassette do not.
Can I use tap water?
Dimplex allows normal tap water in the Opti-Myst Linear and recommends a softener in hard-water areas. For the Revive and Aura, use filtered water.
Does a water vapor fireplace need a water line?
The e-MatriX does. The Linear is designed for one and can run on refill containers for occasional use. The cassette can go either way. The Revive and Aura are filled by hand.
How often do you clean one?
At least monthly for the Linear, cassette, Revive and Aura. The e-MatriX has a longer residential schedule, listed above.
Can it go in a bathroom?
The Opti-Myst Linear manual allows it if the fireplace is on a GFCI-protected circuit or receptacle and installed where water cannot enter the unit. It is not watertight. Local electrical code applies.
How long does the transducer last?
Dimplex gives no fixed life for the Linear and supplies spares. For the e-MatriX it specifies replacement every 12 months in residential use.
Planning a water vapor fireplace? Tell us the wall, the water access and whether you need heat, and we will confirm the right model and send the installation guide before you frame. Call 877-879-9191 or contact us.
Sources: Dimplex Opti-Myst Linear Installation and User's Guide 7216400100R03; Faber e-MatriX manual 7216170100R01; Dimplex Opti-Myst Pro cassette manuals 7214300200R05 and 7217010200R01; Opti-Myst Revive manual 7216930100R00; Opti-Myst Aura manual 7216940100R00. Warranty terms vary by model, so ask us for the current terms before you order. Electrical and plumbing codes vary by jurisdiction. This article does not replace the manufacturer instructions or a licensed electrician or plumber.