Thursday, November 10, 2011

Mulberry Stoker Inset Stove


A First Look at 
The Mulberry Stoker
Inset Stove


I had a long and very interesting conversation recently with Peter Hughes of Mulberry Stoves Ireland. Peter really knows his stuff and answered my many questions regarding the design principles, operation, materials, installation, efficiency, fuel, and maintenance of solid fuel inset stoves.

Why am I telling you this? The reason I mention it is because it gives me confidence to know that there is an individual in a company who is a competent engineer, and who fully understands the scientific design and operating principles involved in their subject.

The Stoker Inset

The Mulberry Stoker is a bit different in its basic shape from the many run of the mill inset stoves on the market. It presents an unfussy look with modern simple clean lines.

I am looking here, in this posting, at the non-boiler version of the Mulberry Stoker. There is also a stove available with a built-in boiler.

One very different feature of the Stoker is the fire box, which appears to project outwards into the room in a unique "Bay Window" formation. This feature allows a very wide angle view of the fire, but it also presents a larger surface area to the room thus allowing more heat to radiate and convect to the room space.

This would appear to be reflected in the higher rated output of 6.5kW. A figure of between 5 and 6kW is about average. The Mulberry also has a notably higher efficiency of 76%. A certified efficiency of 76% is unusual in an inset stove. Efficiency of 70% would be considered good, 76% is closer to the efficiency of a free standing stove and is excellent for an inset.

Note the Dormer fronted Fire box

All of the castings which come into contact with the fire, such as grates, baffles etc., are done in 17%.hi-chrome iron. This makes them resistant to burning out and therefore longer lasting.

The Convection Airflow Pattern


The Stoker inset is a bit more expensive than the Blacksmith Anvil. The list price is just over €1000 but it can be purchased a deal cheaper than this. Walsh Bros. Tullamore currently have it on a special offer at €795.

Manufacturer Specifications

• Maximum output 6.5kW
• Maximum fuel consumption 0.93kg per hour
• Efficiency of 76%
• Clean burning with low emissions - O.26% CO (at 13% O2)
• Long lasting 17% Hi-Chrome castings in grate and firebox
• Unique bay window gives wide view of fire
• Window air wash for clean glass
• Provides both Convection and Radiant heat
• Will burn overnight
• Easily installed – DIY fitting in 15 minutes
• Works perfectly in normal chimney
• Can be used with or without flexible flue liner
• Guaranteed Irish – manufactured in Ireland
• Certified to EN 13240 and CE approved
• Manufactured by company certified to ISO 9001
and ISO 14001

I have not had a chance to see this stove working as yet, so I can give no assessment of its actual performance. When I get to examine one close up I will inform the blog with an update.


1 comment:

Joe said...

Hi, I saw your piece on the Mulberry Stoker and prompted me to do some investigation of my own as I would like to install a multi-fuel stove inset into my fireplace, preferably without removing the fireback. I only light the fire occasionally to supplement my oil-fired heating. What's concerning me slightly about a self-install - straight into the existing fireback and conventional clay chimney without a separate stainless steel liner, are all the scare stories about chimney fires caused by these high-efficiency stoves and insurance companies not covering the consequential damage. The instructions for several of these inset stoves (including the Stoker) indicate that the stove can be installed without a liner (or a stub connection to the existing flue) or alternatively can be installed with a liner but then the existing fireback would need to be removed. Now if there was a regulation that these devices must be installed by a certified installer and you got a certificate to prove safe installation it would be all and good, but there doesn't seem to be a lot of clarity about what constitutes best practice. The industry seems to be self-regulated and no government body is overseeing the process of stove installs (incl. SEAI)! Have you any information on whether a self-install of one of these stoves would be used by an insurance company to evade pay out should there be a subsequent chimney fire?