Insulating The Izzo Alex Mk II (polyester batting)

This describes the insulation of an Izzo Alex MK II using polyester batting (fire retardant)

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In the parent page to this one you will see that Dave C insulated his Alex MK I sometime last year (i.e. 2007). I read it at the time and realised this was beyond me for my Alex. When 2 of us collected our GC4 beans this month, Dave C tagged along (March 2008) and the subject of insulation came up during the return journey. Dave was talking about the suitability of polyester batting and mentioned a shop we could easily detour to.

I stupidly became enthusiastic about it so a short while later I was returning home with 1 metre of this stuff and I was then obliged to go through with it. Believe me, I have neither the patience nor the skill for tasks such as this.

Some while later, I spent an hour thinking about it, moaning to Dave, thinking more, moaning to Dave, thinking even more and finally resigning myself to having a go.

Miraculously, it actually took me less than half an hour once I was started. Quick summary:

  • it works really well. Boiler on/off times are noticeably iproved meaning my machine is using less energy than before, prior to insulation the on/off cycle was about 10s/1m05s. After insulation and at about an hour after switch-on to thoroughly warm through this was 10s/1m50s. However, it was pointed out to me that after another hour this became 2m15s
  • I simply removed the case to install, no inteernal components or wioring needed to be disconnected
  • the material compresses and is therefore easier to work with than it first looks
  • I received no cuts (on the forum John Y seems to have suffered this using silicon for his Fracino)
  • it is really cheap (I read on another forum about a group buy of expensive silicon - £30+ if I recall correctly). The amount of polyester batting I took home cost £2.50
  • I used only 2 strips of approx 40cm x 15cm. If I had got this wrong I had plenty left over to get it right!
  • To check how long I needed the strips to be I wrapped a piece of string around the boiler and put that on the batting to mark the cut point - adding some extra on just in case
  • check out the linked article by Dave on the safety experiments we carried out when he came round

That's the words over, this article is mostly pictures (click on any image to enlarge). Here goes:

1 below. The sheet of polyester batting used


2 below. Fitting the 1st of the 2 strips (around one end of the boiler)


3 below. Alternative view of the 1st strip (I left enough at the end to tuck it in)


4 below. The 2nd strip (I realised this would be trickier to work so so I threaded it with string to allow me to push and pull it round the boiler simultaneously)


5 below. Fitting the 2nd strip


6 below. Alternative view of the 2nd strip


7 below. All done - end view (the material tucks in easily so there is no need to tie with string or other types of fastener)


8 below. All done - top view


9 below. Outer double skinned case and inner top plate re-fitted (these do provide some insulation by themselves)


10 below. Outer top plate re-fitted (which also helps the insulation)


11 below. Top plate protector in place (and the top plate still warms the cups and baskets and dries items nicely)


12 below. The batting I had left over and the various tools I used (spanner and screwdriver for the Alex case)


Cheap, simple, effective and safe. Well worth doing.

Paul L