The following are arguments for insulation even if basic for your boiler.

I am basing this on the 3.9L boiler on the Rancilio S-27.

Before the insulation the time to Vacuum release seal was...

12Min 30Sec.

After the wrap, nothing on the top or bottom, only the sides with buffalo snow...

10Min 53Sec. to the vac seal closing.


Beyond that...

16Min 20Sec for the initial pressure cut off at 1.2 bar. Without the insulation.

With it...

14Min 50Sec.

And not that great a insulation job. That is with just poking the insulation where I could get it in. As I said the top and bottom of the boiler are still uncovered.

I expect at least another 25% gain once I get them on.

Bottom line is get something on there ASAP.

-Cecil

So, your argument for insulation is just faster warm-up times? Not that I'm complaining about faster heat-up, but dramatically improved power consumption and heat shedding is a much bigger deal for me.

Well Nick,

It's not that I don't see substantial decreases in the cycle times, but more that I didn't record them. So I do not have the data points to clearly back them up. I can say that the heater on time to off time ratio has gone down, in a clearly obvious way but I do not have the numbers.

I guess I wanted to state the data I had, and not distract from it.

-Cecil

That sounds good. I think most of the people that have approached insulation have focused on steady-state cycle time improvements, since if you keep your machine on most of the time (e.g. all day) this is the biggest factor in reduced energy consumption. It's no surprise that insulation, since it reduces heat loss from the enclosure, would enhance the startup time of your machine and indeed speed the time it takes to get to a stable state, heat-wise. This may be of keen interest to people who turn their machine on only when needed, so thanks for your numbers.

After insulating(KO Wool) the steam boiler in my S1V2 I saw a 42% reduction in the frequency of the heating cycles. The steam boiler in my Speedster comes insulated with a thin but very effective foam material. The rear portion of the cup warmer rail which sits directly over the S/B doesn't even get warm unless there are cups touching it to conduct heat from the cover.

I insulated the boiler on my A3 some time ago. It makes the boiler cycling much less which shaves $$$. It runs 24/7 so even a slight reduction in boiler cycles will add up. Now if you have a PID controlled system, you do not want to insulate the boiler. The boiler needs to lose heat. It helps the PID tune itself. There was a more detailed discussion on it in another thread.

cannonfodder wrote:Now if you have a PID controlled system, you do not want to insulate the boiler. The boiler needs to lose heat. It helps the PID tune itself. There was a more detailed discussion on it in another thread.

Are you referring specifically to an HX machine? The Speedster boilers are both PID controlled and the steam boiler is insulated.

As to not insulating PID machines, wouldn't the PID just learn a different curve?

I have a 110v single HX Futurmat with an 8L boiler and a 220v single HX Astoria with an 8L boiler. They are both uninsulated and live in different places. There is a difference in the warm up time and recovery speed for these that is much greater than what Cecil's numbers are showing and I think people have "successfully" installed PID on machines similar to the ones that I have. The only thing that insulation would seemingly do is make the coast down out of an over temperature situation longer, so it would be a patience thing on the part of the user?

Good job Cecil in figuring out a low-tech way to get some performance numbers on boiler insulation that removes a lot of variables like heater wattage, voltage, PID vs. pressurestat etc.

WES

With a PID-controlled insulated boiler there is a higher performance penalty from overshoot. Since there is no active cooling, it takes a little extra time to passively settle back down if the temperature has significantly overshot the mark.

But this is a manageable problem, usually solved by increasing derivative gain. IMO, this inconvenience is not a good enough reason to forgo the many benefits of insulation.

Jim

JohnB. wrote:Are you referring specifically to an HX machine? The Speedster boilers are both PID controlled and the steam boiler is insulated.

Steam boiler yes, brew boiler, no. While you can put a PID on a HX machine I don't see any real need for it. I believe we obsess over uber flat temp profiles simply because it is one of the few variables that can actually be measured.

As Jim mentioned, the arguments I have seen against insulating the brew boiler on a PID machine have to do with the derivative (margin of error) or the D in PID for those not familiar with PID function. You should be able to compensate in the programming of the controller but most suggest not insulating the brew boiler because it hinders the accuracy of the PID.