More on boiler insulation

[BradS]

First of all - thanks to all the espresso research workhorses here who do so much research and sharing in order to further the coffee experience for all. If I am any example, your help reaches many people.

I decided early-on that I wanted to insulate the boiler in my Elektra T1 for power consumption reasons, and after accomplishing the task, I think I may have rushed into it somewhat. The consensus here seemed to be that ceramic blankets were the way to go, but now I am not so sure. Granted, the ceramic may achieve what your goal is, give or take somewhat, but after looking closer, it looks to me like melamine foam is the most effective (and most cost-effective) way to accomplish the task. Not to mention the fact that I did not really care for all the dust and mess associated with the ceramic blanket (I used the 1/2" Kaowool brand alumina ceramic blanket listed in the photo below supplied by McMaster Carr).


revised 3/15/2008 to add Melamine Foam info

So, unless my calculations are off, the fiberglass would be the choice, with comments:

1. 1" thickness fiberglass blanket is pushing the limits of workability and 1/2" is harder to procure. It may be necessary to compress the blanket more than you would like, reducing it's efficiency somewhat.

2. The K-factor for fiberglass (which is irrespective of the thickness used) or melamine foam is significantly better than ceramic or silicone in general.

3. The R-value for the examples given (which is respective of thickness) is significantly better for fiberglass and melamine foam.

4. The cost per square foot is significantly better for fiberglass and melamine foam, granted the sizes you may be forced to buy for each will vary.

5. Fiberglass or Ceramic either are relatively messy to work with compared to the silicone or melamine foam options.

The most attractive installation would likely be silicone or urethane foam rubber if done properly. However, the cost effectiveness for silicone was the worst of all three options, and without consideration to cost was still inferior to fiberglass. In any event, I have already done mine with ceramic and am mostly pleased with the results, considering it is nice to still have some cup warming ability along with much less heat-on time. However, if I did it again (and I just might if free time allows), I would likely use the melamine foam. The point here was just to share the research with folks who may be contemplating this modification.

Here is a picture of the results (it is encased in copper mesh just to keep it a bit tidier):



Cheers,

Brad
edited 3/15/2008 to add melamine foam info

[another_jim]

If you enjoyed the mess of the ceramic, you'll be ecstatic when strands of fiberglass start cutting into your hands (and lungs, if you're not wearing a mask).

[BradS]

If you enjoyed the mess of the ceramic, you'll be ecstatic when strands of fiberglass start cutting into your hands (and lungs, if you're not wearing a mask).

I've been there! And yes, I would definitely recommend a respirator or mask and latex gloves. That's also why, if I did the job with fiberglass insulation, I would wrap it with the high-temp tape to keep any fibers from coming free. In fact, I would probably use the tape on ceramic too. I don't know if people using other brands of the ceramic blankets had the same experience, but when I was done working the blanket with gasket punches and scissors, I had a respectable pile of silica dust laying on the bench.

Cheers,

Brad

[DaveC]

The link below shows the product I used to insulate my Izzo Alex. Luckily for you guys, it's available in the US (manufactured in US). Seriously read the article all the way through, it's not a joke and 7-8 months on the product remains stable.

http://coffeetime.wikidot.com/ins...er-on-an-izzo-alex

[cafeIKE]

After reading the MSDS, and although the ratings are probably overly cautious, even if ceramic was free, no amount of persuading could convince me to use it :

HAZARD CLASSIFICATION

Although studies, involving occupationally exposed workers, have not identified any increased incidence of respiratory disease, results from animal testing have been used as the basis for hazard classification. In each of the following cases, the conclusions are qualitative only and do not rest upon any quantitative analysis suggesting that the hazard actually may occur at current occupational exposure levels.

In October 2001, the International Agency for Research on Cancer (IARC) confirmed that Group 2b (possible human carcinogen) remains the appropriate IARC classification for RCF.

The Seventh Annual Report on Carcinogens (1994), prepared by the National Toxicology Program (NTP), classified respirable RCF and glasswool as substances reasonably anticipated to be carcinogens.

The American Conference of Governmental Industrial Hygienists (ACGIH) has classified RCF as "A2-Suspected Human Carcinogen."

The Commission of The European Communities (DG XI) has classified RCF as a substance that should be regarded as if it is carcinogenic to man.

The State of California, pursuant to Proposition 65, The Safe Drinking Water and Toxic Enforcement Act of 1986, has listed "ceramic fibers (airborne fibers of respirable size)" as a chemical known to the State of California to cause cancer.

The Canadian Environmental Protection Agency (CEPA) has classified RCF as "probably carcinogenic" (Group 2).

The Canadian Workplace Hazardous Materials Information System (WHMIS) - RCF is classified as Class D2A - Materials Causing Other Toxic Effects

The Hazardous Materials Identification System (HMIS) -

Health 1* Flammability 0 Reactivity 0 Personal Protection Index: X (Employer Determined)
(* denotes potential for chronic effects)

When done with the silicone foam insulation, I had no itchy skin, no gritty eyes, no dust, no bits, nada to clean up.
There is ZERO possibility of fibres floating around in the future. THAT peace of mind is well worth the tariff.

Should the need ever arise, I can cut 4 tie wraps and remove the insulation in under 5 minutes.
Double that to reinstall.

[jesawdy]

Wow, both are seriously neat installations. Nice work guys.

I have a machine that has a 4.5-liter copper boiler that was uninsulated. I used a ceramic felt product simply because I could get it locally at a heating supply house and it was pretty cheap for the quantity I needed. The product was labeled "Roll Pyrofelt Gasket - (1/4" x 12")" and was sold by the foot for ~$3 per foot. The material I used was only 1/4", but I wanted it to be somewhat lossy to still have an effective cup warmer. It certainly reduced pressurestat cycling significantly and you can rest your hand on the hot boiler no problem. It was a messy product and I wore latex gloves... if you have to work with it for any length of time, a dust mask would be wise. I also wouldn't recommend it in any exposed application... you just don't want to touch or disrupt it. I secured the felt to the boiler with a few wraps of copper wire and stitched the ends on with the same, much like Bob Barraza did on his Elektra in Insulating the Elektra A3's boiler. I also used the wire to "tie down" the boiler to the frame, but I first cut some silicone tubing lengthwise to fit on the edge of the metal boiler supports (to keep from cutting into the insulation and to help dampen any vibration). This ceramic felt product also does not fair well with a lot of handling, as it will tear if stressed, so you need to plan accordingly.

I can certainly see how the foam product Ian used would be much nicer to work with.

[BradS]

After reading the MSDS, and although the ratings are probably overly cautious, even if ceramic was free, no amount of persuading could convince me to use it :

Definitely a good point, and yes it's likely overstated. Your installation looks very good, BTW. For folks following along, here are the MSDS for all three products (or an equivalent):

Fiberglass Insulation Blanket

Ceramic Insulation Blanket

Silicone Foam Rubber


Cheers,

Brad

[k7qz]

When done with the silicone foam insulation, I had no itchy skin, no gritty eyes, no dust, no bits, nada to clean up.
There is ZERO possibility of fibres floating around in the future. THAT peace of mind is well worth the tariff.

Should the need ever arise, I can cut 4 tie wraps and remove the insulation in under 5 minutes.
Double that to reinstall.

Nice! That looks like the insulation material of choice for me. Where did you pick this material up? I asked at my local heating and sheet metal shop on the way home from my office today and the man at the counter gave me the "deer in the headlights" look which I took as "I don't have a clue what you're talking about"...

[cafeIKE]

Nice! That looks like the insulation material of choice for me. Where did you pick this material up? I asked at my local heating and sheet metal shop on the way home from my office today and the man at the counter gave me the "deer in the headlights" look which I took as "I don't have a clue what you're talking about"...

It's from McMaster-Carr.
It's FDA Approved 1/2" Extreme Temperature Silicone Rubber
It ain't cheap. About USD150, but there is enough for two or three < 2L machines.
I used about 7" of the 24" to do the Vibiemme. Sold the rest.

[2xlp]

i bought the remainder of the above silicon..

insulated 2 of my machines ( expobar + isomac ), gave away the rest to a friend who did his brewtus

silicon foam is the only option -- UNLESS -- you have an external rotary pump. if you have an internal pump (vibe or rotary), i think you're crazy using ceramic/fiberglass . the vibrations & air current will loosen up enough strands to get in the air and make me worry.

[BradS]

i bought the remainder of the above silicon..

insulated 2 of my machines ( expobar + isomac ), gave away the rest to a friend who did his brewtus

silicon foam is the only option -- UNLESS -- you have an external rotary pump. if you have an internal pump (vibe or rotary), i think you're crazy using ceramic/fiberglass . the vibrations & air current will loosen up enough strands to get in the air and make me worry.

It's by no means the only option when it's 42 times the cost and has 1/3rd the insulating value of the fiberglass example. In fact it's not even considered a thermal insulation by McMaster or other vendors who handle it. Further, if fiberglass was unsafe or impractical for interior insulation in a motor-driven appliance, virtually every appliance manufacturer wouldn't have put it in virtually every dishwasher, refrigerator, dryer etc. for the past three decades and beyond. Granted, it is more cumbersome to fabricate and should best be faced or sealed, but the numbers clearly show it's superior (for anyone who knows how to install it without wrecking themselves. If not, then foam rubber is likely the choice for you.)

Not to mention, its' pretty amazing stuff if a 24" X 24" sheet could insulate 4 espresso machine boilers! That at least gets the cost down in the $35.00/per range for inferior thermal insulation.


Cheers,

Brad

[Grandma]

What about fiberglass insulation paper (mcmaster 9323K21)? Am I mistaken to think it stays together like paper, so it doesn't have the mess issue of other fiberglass options? It's only 1/8" thick, but with a k-factor of .21, that's still a .595 r-value. At $24 for 10' a double wrap might be a decent cost/efficiency/cleanliness tradeoff.

[BradS]

What about fiberglass insulation paper (mcmaster 9323K21)? Am I mistaken to think it stays together like paper, so it doesn't have the mess issue of other fiberglass options? It's only 1/8" thick, but with a k-factor of .21, that's still a .595 r-value. At $24 for 10' a double wrap might be a decent cost/efficiency/cleanliness tradeoff.

That is very good for a 1/8" piece of insulation. Don't know how easy it would be to conform to the shape of the boiler without leaving a lot of air gaps though. That's the problem with semi-rigid insulations for this type of use. Fiberglass tape would seal the joints well enough, but it would be tough to cover any compound curves like the rounded ends (most) boilers. If your boiler were more squared-off, it might work much better. Just imagine trying to wrap your boiler with poster board.

Cheers,

Brad

[cannonfodder]

I used ceramic insulation on my Isomac and fiberglass for my two group Faema and Elektra A3. I have not died yet. The ceramic was high temperature insulation for stainless steel chimney liners. I actually prefer the fiberglass over the ceramic. If I remember correctly the fiberglass was a fiberglass/wool fabric.

[BradS]

I used ceramic insulation on my Isomac and fiberglass for my two group Faema and Elektra A3. I have not died yet. The ceramic was high temperature insulation for stainless steel chimney liners. I actually prefer the fiberglass over the ceramic. If I remember correctly the fiberglass was a fiberglass/wool fabric.

Just curious, did you prefer the fiberglass for efficiency, ease of installation, or both (over the ceramic, that is)? I have some here (the mcmaster example above) but Lord knows when I'll have time and motivation.

Cheers

[RapidCoffee]

Quick 'n dirty insulation job on my Rancilio L7 boiler:


The kitchen smelled of neoprene for a few days, but the price was right.

[DaveC]

Now don't laugh, but the insulation above looks like one of my mouse mats...sort of polyester covered neoprene

[cannonfodder]

Just curious, did you prefer the fiberglass for efficiency, ease of installation, or both (over the ceramic, that is)? I have some here (the mcmaster example above) but Lord knows when I'll have time and motivation.

Cheers

The ceramic was messy, and aluminum backed. A month or two after I wrapped the boiler on my Isomac, it stopped working. The thermal fuse plug was ever so slightly exposed and had arced to the aluminum backing on the insulation. Baked the fitting and blew the fuse. After that I pulled the backing off.

The fiberglass was easier to work with and appears to insulate just as good or better. I cut a template from some paper, cut the fiberglass mat to match, wrapped the boiler and put a piece of duct tape down the seam to close it. It was quick, simple, cleaner and I think it insulates better. I can lay my hand on top of the boiler after it has been running for an hour or two. It is toasty warm, but not burning hot.

A little trick, don't wrap the insulation too tightly. Insulation insulates by trapping air in the fabric and not allowing it pass from one side to the other. If you wrap the insulation very tight or use something like wire ties or mesh netting to hold it all nice and tight, you kill you insulation's ability to insulate. That is why R-13 insulation is thinner than R-30 and why you dress in layers when it is cold. It may look nice, neat and form fitted, but it does not work as well. My insulation is loose and baggy, more draped over than wrapped and it works wonderfully.

[BradS]

A little trick, don't wrap the insulation too tightly. Insulation insulates by trapping air in the fabric and not allowing it pass from one side to the other. If you wrap the insulation very tight or use something like wire ties or mesh netting to hold it all nice and tight, you kill you insulation's ability to insulate. That is why R-13 insulation is thinner than R-30 and why you dress in layers when it is cold. It may look nice, neat and form fitted, but it does not work as well. My insulation is loose and baggy, more draped over than wrapped and it works wonderfully.

Yeah, I definitely agree. That mesh isn't as tight as it looks, though. In fact the stuff is about .006" thick, so it exerts barely enough pressure to keep the insulation from sagging away from the lower part of the boiler. What I really want to do is the fiberglass insulation wrapped with fiberglass tape, but like you say, the tendency would likely be to compress the fiberglass as you wrap it. I'll probably do that eventually.

Cheers,

Brad

[k7qz]

I used ceramic insulation on my Isomac and fiberglass for my two group Faema and Elektra A3. I have not died yet.

I think the key word in that sentence is yet...

Hmmm, I wonder if something as simple as buying a small water heater blanket at Home Depot or the likes would work? Fiberglass insulation with a built in vinyl type of cover on it with attached tape strips to hold it in place- You'd also have enough left over to do all the other boilers of HB members that live in your town as well...