Secondary water storage for gasification units

[Scotty2]

I noticed that many gasification wood boilers show 50-100 gallon water capacity. Is the recommendation to add a second storage tank, particularly if heating a radiant slab? Is this a bit of an improvement over a Garn (with built in massive water storage), whereby I can bypass the secondary tank to bring the slab or whatever is being heated up to temperature faster, then bring the second tank back online?
Regards, Scotty

 

[Bob Rohr]

I noticed that many gasification wood boilers show 50-100 gallon water capacity. Is the recommendation to add a second storage tank, particularly if heating a radiant slab? Is this a bit of an improvement over a Garn (with built in massive water storage), whereby I can bypass the secondary tank to bring the slab or whatever is being heated up to temperature faster, then bring the second tank back online?
Regards, Scotty

There are a number of ways to pipe a buffer tank to the boiler. The two pipe method, shown below, allows the heat energy to travel to the load before the buffer tank is heated, or while it is being heated.

Here is a link to a good journal showing various options and the pros and cons of them.

http://www.caleffi.com/sites/default/files/coll_attach_file/idronics_17_na.pdf

 

[maple1]

Also/or, if your loads are plumbed in to the top of your storage tank, you will be pulling hot water to them pretty well as soon as the boiler sends hot water to the tanks. No bringing things online or taking things offline. Storage can be so simple to implement remembering a couple of fundamentals - hot water goes up & cold water goes down, and the flow will tend to follow the path of least resistance.

(Mine is plumbed more like Bobs diagram though).