Warpfive Glasshopper

  • Ultra low start-up temperature 70° C (158° F)
  • Operation is quiet due to the use of a Borosilicate glass piston cylinder
  • Uses a large 4 blade high aspect ratio fan (285mm, 11.2 inch diameter) and circulates in excess of 260 CFM
  • Designed and produced in Great Britain
  • Lifetime manufacturer warranty


How is the Warpfive Glasshopper Stove Fan Powered?

Warpfive makes some of the most distinctive looking stove fans on the market today.  The reason for their stylish and unusual look is due to the way they’re constructed.  Most stove fans rely on the Seebeck Effect to turn heat from your stove into power for the stove fan.  In this manner, stove fans do not have to rely on electricity or battery power to function, which increases their efficiency dramatically, and as a consequence, increases the efficiency of your wood stove as well.

The beauty of the Warpfive Glasshoppers stove fan

Warpfive’s fans also rely on the heat your stove produces to provide power for their fans, but they use a different methodology.  Their fans all come equipped with small Stirling engines, which are powered by that heat.  The end result is the same – heat from the stove provides all the power the fan needs to function, but Warpfive’s fans arrive at that destination by a different road.

The result is a very distinctive and elegant looking fan.  While most other stove fans on the market today are small, unobtrusive and barely noticed by family and friends, Warpfive’s offerings are small, yet eye catching.  Attractive enough to add something your home’s décor, even as they help even out the temperature in your living space.


What is the Glasshopper Model Designated For?

The Glasshopper is one of a number of fans that Warpfive manufactures, and it’s an interesting entry in their lineup.  Specifically engineered to operate at lower temperatures, it’s ideal for fires that don’t burn as hot and are fed fuel regularly, or on top of cooler stovetops (especially Soapstone).  In addition to being attractive and functionally brilliant, the fan features a clear Borosilicate glass cylinder, which allows you to see the rhythmic displacer.  It’s actually mesmerizing to watch in action.

The Power Plant of the Warpfive Glasshoppers stove fan

What Are The Dimensions?

Dimensionally, the Glasshopper is a scant 11 centimeters wide (four inches), and just 32.5 centimeters high (roughly a foot tall), and weighs just 998 grams (about two pounds), making it simple to set up and reposition as you like.  Further, its four-blade fan design allows for a surprising amount of air circulation for such a small fan – the Glasshopper is capable of pushing an impressive 260 cubic feet of air per minute, making it suitable for rooms of most sizes.


Where Is It Manufactured?

Whereas most stove fans are designed to operate at much higher temperatures, sometimes, and in some circumstances, this is not optimal, or even desired.  Extra engineering is required to fashion a stove fan that will operate at lower temperatures, and you generally pay a premium for the feature, and this is true in the case of the Glasshopper as well.  As of the time of this review, they could be found online for £218.99.  That’s certainly not cheap, and in fact, may be out of some people’s budgets, but this is definitely a case of getting what you pay for.  Each tiny Stirling engine is hand crafted in England, and the fans are built of durable stainless steel, brass and aluminum, meaning that in the overwhelming majority of cases, barring some mishap or another, they’ll last far longer than the generous three-year warranty the company includes with each fan they ship.


The Warpfive Glasshopper’s Temperature Range

Operationally, the Glasshopper is designed to begin functioning at temperatures as low as 70 degrees Celsius (158 degrees Fahrenheit), with an upper temperature range of 300 degrees Celsius (572 degrees Fahrenheit).  When you compare this to many other stove fans, including the MK6, also made by Warpfive, you see the difference in the rage.  The MK6, for example, is designed to operate in a temperature band between 230 degrees Fahrenheit / 110 degrees Celsius and 842 degrees Fahrenheit / 450 degrees Celsius.  A stunning difference, and a triumph of engineering by the folks at Warpfive.



The air moving capacity of this fan makes it perfect for most homes.  The low temperature operation is ideally suited for stovetops, allowing you to have the stove you use for cooking pull double duty to also heat your living space, which is great for people living off grid, as anything that can be done to improve the efficiency of any appliance heating your home is a welcome addition indeed.  In addition to that, the Glasshopper is more than just a functional device, it’s also attractive enough to be considered a home accent in its own right.  If aesthetics matter to you, in addition to function and performance, it’s hard to beat the products Warpfive makes.



Having said all that, the Glasshopper is not for everyone.  If you don’t have a stove that you operate at lower temperatures, and you don’t use your cooking stove to help heat your home, then this probably isn’t the fan for you.  There’s no point in paying extra for low-starting temperature functionality if that’s not what you need.  If you run a hot wood stove, you’re far better off getting a fan that’s designed around that, and in those cases, you’ll find any low temp. fan (the Glasshopper included) to be somewhat underwhelming, even if it has the air moving capacity to suit your needs.

The other downside is the cost.  At the price referenced above, the Glasshopper simply may be beyond the budgets of some consumers.



The Glasshopper isn’t for everyone, but for the segment of the market it was designed for (those who regularly rely on low temperature stoves to assist with home heating), it’s quite possibly the perfect fan.  There are other low temperature fans on the market, and many of them cost less, but none of the Glasshopper’s competitors can touch it in terms of quality, durability and attractiveness.  An excellent choice for a certain segment of the market.