Real Fyre Carrera Marble Vent-Free Fyre Spheres are a contemporary alternative to gas logs: 4 inch ceramic spheres stacked on a vent-free burner that heats the room with the damper closed. They are made for one burner, the Real Fyre G23, and are sold with it. Each sphere has a hole underneath that sits over a peg on the burner, so the stack stays exactly where Peterson tested it. You choose the size that fits your firebox and the remote you want.
Peterson certifies this burner two ways: as a vent-free room heater, and as a vented decorative appliance. Where vent-free heaters are not allowed, the same set can be installed with the damper clamped open.
- Fuel: natural gas. Need propane? Add a note to your order and we will confirm the propane version with you before anything ships.
- Sizes: 18 inch with 16 spheres, 24 inch with 22 spheres.
- Finish: Carrera Marble.
- Burner: Real Fyre G23 with an oxygen depletion sensor (ODS) safety pilot.
- Heat: up to 37,000 BTU per hour.
- Controls: on/off remote, or electronic variable remote.
- Made by: R.H. Peterson Co. in City of Industry, California.
Who it's for
Right buyer. You want heat from the fireplace as much as the look, your local code allows vent-free heaters, and the room is large enough for the burner; the Carrera Marble set fits a wood-burning fireplace or a listed vent-free firebox.
Wrong buyer. You live where vent-free is not permitted, the set would go in a bedroom or bathroom, or you would rather not have any moisture or odor from a fire in the room; a vented set is the answer.
Will it fit?
Is vent-free allowed where you live?
Check before you order. California does not allow vent-free gas heaters in homes, and some other states, cities and counties restrict them. Your building department or a local gas installer can tell you in one call. If vent-free is not permitted, this set can still be installed as a vented log set: the damper is clamped open and the chimney must be at least 15 feet tall.
Measure the inside of the firebox: width at the front, width at the back wall, depth and height. Both sizes need 15 inches of depth and 17 inches of height. The burner sits centered, is fastened to the firebox floor with the screws provided, and must not be pushed all the way to the back.
| Size | Front | Back | Depth |
|---|---|---|---|
| 18" | 24" | 20" | 15" |
| 24" | 30" | 22" | 15" |
It may be installed only in a masonry or UL-127 factory-built wood-burning fireplace, or in a listed vent-free firebox. Do not use it in a factory-built fireplace whose instructions say it has not been tested for vent-free burners. The firebox floor cannot have an ash lip or a sunken hearth deeper than 3/4 inch.
Clearances
In a factory-built fireplace, follow that fireplace maker's clearances. Otherwise Peterson requires:
- Side walls: 6 inches from the side of the fireplace opening to a combustible side wall.
- Ceiling: 42 inches from the top of the opening.
- Above the opening: at least 12 inches of noncombustible material such as brick, stone or marble. With a fireplace hood, 10 inches.
- Mantel: how far a wood mantel may stick out depends on its height. At 20 inches above the opening it may project 2.5 inches without a hood, or 10 inches with one. The manual has the full chart.
- Floor: if the burner sits less than 6 inches above the floor, 12 inches of noncombustible hearth in front of the fireplace.
If you cannot meet these clearances, Peterson says the set must be run with the chimney damper open. A fireplace hood is strongly recommended under a wood mantel.
Heat and gas
Is your room big enough?
A vent-free fire takes its air from the room, so the room has to be large enough for the burner. The rule in the National Fuel Gas Code is 50 cubic feet for every 1,000 BTU. Multiply the room's length, width and height in feet, then multiply by 20: the answer is the most BTU the room can take. Rooms that open into it without a door count as part of the space.
| Size | Heat input, high | Low setting | Smallest room | With an 8 ft ceiling |
|---|---|---|---|---|
| 18" | 28,000 BTU | 22,000 BTU | 1,400 cu ft | about 175 sq ft |
| 24" | 37,000 BTU | 28,000 BTU | 1,850 cu ft | about 231 sq ft |
The low setting is available with the electronic variable remote. Vent-free heaters over 10,000 BTU may not be installed in a bedroom or a bathroom, so this is not for those rooms. In a very tightly sealed home, or above 2,000 feet, you may need to open a window an inch or two while it runs.
Choose your options
Control
On/Off Remote. A standing pilot plus a handheld remote that turns the fire on and off. Runs on batteries that come in the box.
Electronic Variable Remote. Electronic ignition with an on-demand pilot, so no pilot burns while the fire is off, plus flame height on the remote. Runs on batteries that come in the box.
Installation
A vent-free set goes into a wood-burning fireplace, with the damper open or closed, or into a listed vent-free firebox, by a licensed gas installer.
- Where it is allowed: not in California, not in bedrooms or bathrooms in most states, and not in a room smaller than the burner's minimum; check the room-size table on this page and your local code before ordering.
- Gas: a dedicated 1/2-inch line with a shutoff; the burner's ODS pilot shuts the gas off if the room's oxygen drops.
- Clearances: the mantel and side-wall distances on this page are the burner's own; they apply whatever fireplace it goes into.
- Logs: placed exactly by the diagram; a moved log on a vent-free burner makes soot.
- Controls: manual, remote or thermostat; the electronic versions take batteries or a 110-volt outlet in the firebox.
What arrives
- Sphere carton: the full set for your size. Use exactly that number. Peterson warns that adding spheres makes the burner unsafe.
- Burner carton: burner with valve and ODS pilot assembled, removable front cover, remote and batteries, gas connector, floor screws, a damper clamp for vented installations, and black glass to spread on the firebox floor around the burner (10 lb with the 18 inch, 15 lb with the 24 inch).
Before you order
- It is a supplemental heater, not the main heat for a home, and it must not be left on unattended or while anyone is sleeping.
- Burning gas makes water vapor. If windows start to fog, open a window or the damper a little.
- Expect some odor and light smoke for the first four to six hours of use while factory coatings burn off. Ventilate well during that time.
- Candles, air fresheners, sprays and fresh paint in the room can cause odors when the fire is on.
- Keep ceiling fans and vents from blowing into the fireplace. Glass doors must be fully open and a screen in place.
- Have it cleaned and checked by a qualified technician at least once a year. Peterson requires it for the warranty, and the ODS pilot is sensitive to dust, lint and pet hair.
- Installation is by a qualified gas professional. In Massachusetts that must be a licensed plumber or gas fitter.
- Some soot on the spheres is normal with this burner, Peterson says. Soot in the firebox or the room is not, and means it needs service.
- Do not burn wood in the fireplace once it is installed.
How it performs
The Carrera Marble Vent-Free Fyre Spheres vent-free set is a heater that looks like a fire: all of the burner's heat comes into the room, so a 30,000 BTU set warms a living room the way a small furnace would, with the logs glowing red where the flame runs through them. The flame is blue at the base and yellow above, lower and tighter than a vented flame because it burns clean by design, and the ceramic logs radiate heat long after the burner is off. It runs from a knob, a remote or a thermostat, and it can run with the damper shut, which is the whole point.
Trade-offs to know
- A clean-burning flame is a smaller flame; if you want the tall, lazy fire of a wood log, a vented set gives it and a vent-free set does not.
- It puts moisture and the products of combustion into the room. Some people notice the smell on a new set; most do not after the first burns.
- It is not allowed everywhere, and the room must be big enough.
Living with it
Brush the logs gently once a season and never move them from the diagram; a log out of place makes soot on the ceiling. Keep the ODS pilot dust-free. Run a window cracked in a tight house. Change the control batteries yearly.
Specifications
| Sphere set models | US4‑18-CM, US4‑24-CM |
|---|---|
| Burners | G23‑18 and G23‑24, with -12 (on/off remote) or -01V (electronic variable) |
| Fuel | Natural gas. Not field-convertible to propane |
| Inlet pressure | 5 to 10.5 inches w.c. |
| Certification | ANSI Z21.11.2 unvented room heater, and ANSI Z21.60 vented decorative appliance. Indoor use only |
| Warranty | Fyre Spheres: lifetime for the original owner, indoors. Burner: 10 years. Glass: 10 years. Valves, ODS pilots and remotes: 1 year |
Warranty
| Component | Coverage |
|---|---|
| Ceramic refractory logs | Lifetime, for as long as you own them |
| Burner parts, except valves, ODS pilots and controls | 10 years |
| Fyre Glass and spheres | 5 years |
| SPK-26 safety pilot control | 3 years |
| APK-17 control | 2 years |
| All other valves, ODS pilots and controls (batteries excluded) | 1 year |
Source: R.H. Peterson Real Fyre limited warranty, printed in the burner manual linked above. Register the set with Peterson after installation.
Questions people ask
Can I use my vented Fyre Spheres on this burner?
No. The G23 takes only the pegged vent-free sets made for it, in the exact count for the burner size.
Do I need a chimney?
Not a working one. It goes in a wood-burning fireplace or a listed vent-free firebox, and the damper can stay closed as long as the clearances are met.
Can I put it in a bedroom or bathroom?
No. Codes do not allow vent-free heaters of this size in bedrooms or bathrooms.
Can I get it in propane?
Yes, by request. Everything on this page is natural gas. Add a note to your order and we will contact you to confirm the propane version before it ships.
Do I need electricity at the fireplace?
No. The controls and remotes run on batteries that come in the box.
Where is vent-free not allowed?
California bans it outright; many states and cities bar it from bedrooms and bathrooms; some ban match light. Check your local code before you order, and we will confirm the room-size rule with you.
Why does the room need to be a minimum size?
The burner takes its oxygen from the room; the ODS pilot shuts the gas off if oxygen falls. The minimum room volume on this page keeps that from happening in normal use.
Does it make the house damp?
It puts the moisture of combustion into the room, about a cup an hour on high. In a tight house, crack a window; in a normal one, most people never notice.
Manuals and drawings
If you have any questions about this product, please let us know by filling out the form below, and we will contact you as soon as possible.
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