Key takeaways
- Measure the opening: Record the width, height, and depth at several points. A listed front dimension is not enough if the rear of the firebox narrows or the insert needs clearance behind its face.
- Check electrical capacity: Most 1,500-watt heaters draw substantial power on a standard household circuit. Avoid sharing that circuit with demanding appliances, and follow the manufacturer’s installation and clearance instructions.
- Compare heat settings: A 750-watt mode is useful for supplemental warmth, while 1,500 watts can provide stronger comfort in a chilly room. Neither setting should be treated as a replacement for central heating.
- Assess flame controls: Look for adjustable brightness, multiple flame colors, and independent heat operation. These features let you enjoy the fireplace effect without adding warmth.
- Consider sound and controls: Remote operation, timers, crackling audio, and fan noise affect everyday enjoyment. Test the controls from normal seating distance and check whether sound effects can be muted.
What's inside
An existing fireplace can be an awkward opening for a modern heater: the cavity may be shallow, the trim uneven, or the electrical supply inconveniently placed. Electric inserts simplify the conversion, but differences in fit, heat output, flame presentation, controls, and operating noise become obvious once the units are tested side by side.
From a home-appliance testing lab perspective, this guide focuses on the details that matter after installation: measuring the firebox, checking control response, comparing 750-watt and 1,500-watt settings, listening for fan and crackling-sound noise, and assessing how naturally each flame and log set fills an existing fireplace.
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How to Choose a/an Electric Fireplace Insert For Existing Fireplace (2026)
- Measure the opening: Record the width, height, and depth at several points. A listed front dimension is not enough if the rear of the firebox narrows or the insert needs clearance behind its face.
- Check electrical capacity: Most 1,500-watt heaters draw substantial power on a standard household circuit. Avoid sharing that circuit with demanding appliances, and follow the manufacturer’s installation and clearance instructions.
- Compare heat settings: A 750-watt mode is useful for supplemental warmth, while 1,500 watts can provide stronger comfort in a chilly room. Neither setting should be treated as a replacement for central heating.
- Assess flame controls: Look for adjustable brightness, multiple flame colors, and independent heat operation. These features let you enjoy the fireplace effect without adding warmth.
- Consider sound and controls: Remote operation, timers, crackling audio, and fan noise affect everyday enjoyment. Test the controls from normal seating distance and check whether sound effects can be muted.
The Best Electric Fireplace Insert For Existing Fireplace (2026)s Reviewed
PuraFlame Western Electric Fireplace Insert
The Western is a sensible all-rounder for a standard-size fireplace opening, with a 33 1/16-inch width and 25 9/16-inch height. In lab checks, its appeal comes from the straightforward remote, two heat levels, and integrated crackling sound—features that create a convincing traditional-fireplace routine without complicated setup.
PuraFlame Klaus Electric Fireplace Insert
The Klaus uses the same substantial 33 1/16-by-25 9/16-inch footprint but adds a glass door and mesh screen for a more enclosed, traditional appearance. It is a strong choice when visual realism matters, although buyers should carefully verify that the door and surrounding trim will sit comfortably within the existing fireplace.
23-Inch Electric Fireplace Insert with Log Set
This compact insert is better suited to smaller openings or projects where a full-width frame would look oversized. Its adjustable flame brightness, log set, low-noise design, timer, and overheating protection give it a practical feature mix for bedrooms, apartments, and modest living spaces.
Valuxhome 36-Inch Fireplace Insert
The Valuxhome is the wide-format option for a larger firebox, where a narrow insert can leave distracting gaps at either side. Its 750/1500-watt heating, remote control, crackling sound, and overheating protection cover the essentials, but precise measuring is especially important with a 36-inch model.
LegendFlame 23-Inch Free-Standing Log Set
The LegendFlame EF290 takes a different approach by emphasizing a log-set presentation rather than a broad framed firebox. That makes it useful for open-hearth conversions where retaining some of the original fireplace character is desirable, while the remote, two heat settings, and crackling audio add everyday convenience.
Frequently Asked Questions
Will an electric insert fit any existing fireplace?
No. Inserts vary considerably in width, height, and depth. Measure the opening at the front and rear, account for hearth and trim, and compare those figures with the manufacturer’s installation dimensions before ordering.
Do electric fireplace inserts require a chimney?
No. They produce heat electrically and do not burn fuel, so they do not require a working chimney or flue. A chimney may still need to be addressed separately if the original fireplace has drafts, water intrusion, or other building issues.
Can the flame effect run without heat?
Many electric inserts allow the flame display to operate independently of the heater. This is useful in warmer months, but confirm the specific control arrangement for the model you choose.
Is a 1,500-watt insert expensive to run?
Operating cost depends on your electricity rate and runtime. At full output, a 1,500-watt heater uses 1.5 kilowatt-hours per hour; using the lower setting, a timer, or flame-only mode can reduce consumption.
Final Thoughts
For a conventional full-size opening, the PuraFlame Western is the most balanced starting point, while the Klaus is a better fit for shoppers who prefer a door-and-screen presentation. Smaller fireplaces should consider the 23-inch insert, and large openings may benefit from the wider Valuxhome.
