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EcoSmart Fire

EcoSmart Fire Flex 42SS Fireplace Insert

EcoSmart Fire Flex 42SS Fireplace Insert

Regular price £3,695.00
Regular price Sale price £3,695.00
Save £-3,695.00 Sale Sold out

In stock

  • Shares its XL700 burner with the wider Flex 60SS
  • Free UK Delivery
  • 13,650 BTU/h XL700 Ethanol Burner
Burner Finish

🚚 Estimated Delivery Date:

02 September 2026

Delivery date to be confirmed via email once order is placed

Payment methods
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Buying with confidence

  • Manufacturer warranty: 2 years on the bioethanol burner and stainless steel parts, 1 year on everything else.
  • 45 day returns. Unused and in its original packaging.
  • Damaged on arrival? Check it before you sign, and tell us as soon as you can, ideally within 48 hours, so we can sort a replacement quickly. This does not affect your statutory rights.
  • Free UK mainland delivery.
  • Not sure it is the right one? Call, email or chat with us before you order.
  • Overview:
    • The Flex 42SS widens the opening to 1265mm on the XL700 burner, the same burner used in the wider Flex 60SS, giving a genuinely cinematic flame band without the largest sizes’ weight or price.
  • Design & Build:
    • Zinc-sealed mild steel surround and toughened glass, built around a Grade 304 stainless XL700 burner delivering 13,650 BTU/h (14.4 MJ/h) from a 7-litre tank. The burner is available in Stainless Steel as standard, or a Black ceramic-coated finish for a flat, monochrome look, at a fixed premium.
  • What it does well:
    • Runs 9 to 12 hours per fill and is rated for a 90m³ room, comfortably ahead of the 32SS's 80m³. Sharing its burner with the wider 60SS means the same flame intensity, just spread across a narrower 1265mm opening rather than the 60SS's 1725mm.
  • Trade-off worth knowing:
    • At 60kg it’s a genuine two-person install, and 1265mm still won’t fill a wide feature wall the way the 50SS or 68SS do. If the wall is wide enough to take it, the 50SS gives noticeably more glass for a comparatively modest price step up.

Flex 42SS questions, answered

Does the Flex 42SS need a chimney or flue?

No. It runs on bioethanol, which burns clean with no smoke, embers or soot, so there is nothing to vent. It frames into a wall or opening with zero clearance to combustibles - no masonry chimney, gas line or flue required.

Can the Flex 42SS be used both indoors and outdoors?

Yes, it is rated for both. Indoors it needs a room of at least 90m³.

How is the Flex 42SS installed?

It frames directly into a stud wall (wood or metal) or an existing hearth opening, with zero clearance to combustibles required around the frame. There is no gas line, flue or masonry work: once the opening is framed to size, the unit drops in and connects to nothing else. At 60kg it is a two to four-person lift into place depending on the model; check the exact figure on this page before planning your install.

What does the Flex 42SS actually cost to run for an evening?

A full 7 litre fill burns for 9-12 hours. We sell e-NRG bioethanol at £65 for a 20 litre carton, so a full fill is about £23 and a three-hour evening works out at roughly £6 to £8. There is no standing cost, since it only uses fuel while it is alight.

Which Flex size should I choose?

The 42SS shares its XL700 burner with the wider 60SS, giving a genuinely cinematic flame band without the largest sizes' weight or price. At 60kg it is a two-person install; if the wall is wide enough, the 50SS gives noticeably more glass for a modest price step up.

Which fuel does the Flex 42SS burn, and do you sell it?

It runs on e-NRG bioethanol, which we stock in 20 litre cartons. Bioethanol produces no smoke, embers or ash, so there is nothing to clean out after use.

Are there any accessories that fit the Flex 42SS?

Yes. Its XL700 burner takes the XL Baffles and Black Glass Charcoal, sold separately.

Is the Flex 42SS certified for indoor use?

Yes. This model is certified to EN 16647, the UK and EU safety standard for indoor bioethanol fireplaces.

Who the Flex 42SS is for

It is a good fit if:

  • You want the same flame intensity as the wider 60SS, spread across a narrower 1265mm opening instead.
  • You want a genuinely wide feature without the largest sizes' weight or price.

Consider something else if:

  • The wall is wide enough to take more: the Flex 50SS gives noticeably more glass for a comparatively modest price step up.
Model Burner Pick it for Opening width Price Weight
Flex 18SS AB3 Narrowest, fits a tight wall recess or stairwell 578mm £1,495 to £1,795 25.7kg
Flex 32SS XL500 First step up to the XL burner family, nearly double the heat 1010mm £2,995 to £3,445 45.7kg
Flex 42SS (this one) XL700 Shares its burner with the wider 60SS, no log box required 1265mm £3,695 to £4,145 60kg
Flex 50SS XL900 First size offering an integrated log-storage configuration 1470mm £4,095 to £4,595 71.4kg (All Flame)
Flex 60SS XL700 Log box standard, no All Flame option at this size 1725mm £4,545 to £5,095 83.9kg
Flex 68SS XL1200 Largest single-burner size, four configurations at one price 1930mm £4,795 to £5,295 97.1kg (All Flame)
Flex 78SS XL700 Log boxes on both sides as standard, no All Flame at this size 2186mm £4,795 to £5,245 108kg
Flex 86SS twin XL900 First size to need twin burners for full-width All Flame 2390mm £6,995 to £7,995 122kg (All Flame)
Flex 104SS twin XL1200 Even a single log box still runs twin burners 2850mm £7,995 to £8,995 146kg (All Flame)
Flex 122SS triple XL900 First size to run three burners across All Flame 3310mm £9,995 to £11,495 172kg (All Flame)
Flex 140SS triple XL900 Every configuration carries at least one log box 3770mm £11,395 to £12,895 195kg (single log box)
Flex 158SS triple XL1200 Largest and widest in the launch, two configurations only 4230mm £12,395 to £13,895 222kg (All Flame)

Prices are current at the time of writing; follow any link for that model's live price.

Delivery Information

Standard Delivery:

  • Ground delivery to the easiest access point on your property. Does not include inside delivery, packaging removal or assembly.

Bioethanol Fuel:

  • e-NRG Bioethanol may ship separately from your EcoSmart Fire order and can arrive on a different day. A separate tracking number for the fuel order will be emailed to you.

Ship Times:

  • Zone 1 (England / Wales): 5-10 business days.
  • Zone 2 (Scotland / Republic of Ireland / Northern Ireland / Isle of Man): 10-15 business days.
  • Please allow 1-3 business days for the order to be processed before dispatch. Estimated ship times are subject to change due to unforeseen events.

Installation Guide:

  • Full installation and operating instructions: https://cdn.mad-uk.com/media/version/version/ESF-CI-MASTER-FLEX_Series-_FX-V2505_-F-lr.pdf

Key Points of Interest

  • 9-12 hour burn time on a 7-litre fill
  • Indoor or Outdoor rated
  • Stainless Steel or Black burner finish, +£450

Specifications

Category Details
Material Mild Steel (Zinc Sealed, High-Temp Powder Coat) Surround, Toughened Glass; Grade 304 Stainless Steel Burner
Weight 60kg
Dimensions (W x D x H) 1265mm x 365mm x 807mm
Surround colour Black
Burner finish Stainless Steel (standard) or Black ceramic-coated (+£450)
Fuel Bioethanol only (Indoor or Outdoor)
Thermal output 13,650 BTU/h (14.4 MJ/h)
Burn time 9-12 hours per fill
Fuel capacity 7 litres
Minimum room size (indoor use) 90m³
Burner compliance EN 16647 compliant burner (manufacturer-approved)
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