Biomass schematic

[Chalmers7]

Folks can someone explain why / how this system works from what I see the boiler can heat direct to system but once the demand from the system is off the excess heat goes to the buffer tank.is that correct. This is on a Kunzel biomass set up.

also is the thermomix valve set to 60 degrees or higher or lower???

 

[missplumb]

Hi, did you sort this issue out, i'm not familiar with the Kunzel theory of how it should work but this is certainly not the way we would pipe up a biomass system. and yest we would look to set the shunt mixer valve to 60 oC on our boilers, again speak to Kunzel as to what their boilers should run to before they switch to heating mode.

 

[JW Heating]

Most pellet boilers require 55deg back end protection, but this would be down to the manufacturer to stipulate. If you go too low the boiler guarantee would be void.

Interesting that no safety valves are shown on the schematic... careful placement will keep the system safe.

Good Luck.
Wes

 

[Ryan LPS]

Very poorly designed system... :hand:

 

[wifflebat]

Hi
Sorry to hijack the thread a bit, but does anyone know if/how these Thermomix valves are cleaned?
I think I have a problem with mine as the pump is not circulating to the buffer tank (I've replaced the pump which was knackered too but new one has made no difference!)
I can find next to nothing online about this!
What I'm going to try, when the system cools a bit, is to try to remove the cap on the right hand side and see what's in there. I'll post a pic in a bit.

 

[missplumb]

i dont think your hijacking this thread :50:.im not sure about thermomix valves, we always use esbe 3 port valves. some photos would be good.

 

[Ermintrude]

Valves sometimes have mesh in but a real system has a strainer either side. U can clean it when in use by fully opening and closing at full flow rate . But take it off and unscrew cart. There may be crud on the top of the seat preventing lifting of the valve. They generally default to cold side

 

[wifflebat]

Hi
Thanks for the info.
I stripped it and gave it a bit of a clean then put it back together and it seems ok. I tested the cartridge with boiling water and it works so all good.
Here are some pics for those who are into these things...!

https://www.dropbox.com/s/r8q6pj9exfsudy1/Photo 16-08-2014 20 04 08.jpg

https://www.dropbox.com/s/pxffkinf6y5kcmf/Photo 16-08-2014 20 28 25.jpg

https://www.dropbox.com/s/jyu4r6rl9o9nrrj/Photo 16-08-2014 20 28 49.jpg

 

[joe plumber]

Looks like what you said is right. Heats direct or heats buffer. Would make sense to heat buffer then pull heating out of buffer! Although I've seen one system that uses a biomass to preheat a 6" header
in the morning the. Change orientation and heat a buffer in another room. I guess there is no limit to what can be done.

 

[missplumb]

we always pipe into then out of the buffer, as this way you always have a heat store.

 

[Sima07]

The schematic is of a buffer system how the majority is done in Europe not to be confused with an accumulator system.

 

[missplumb]

That is an accumulator system. we would only use this type of system if fitting a log boiler as it needs somewhere for the heat to accumulate after the heating demand has gone. A buffer system is basically a heat store between the boiler and heating circuit and would be used in most woodchip or pellet systems