circ sizing for 1000gallon storage

[Bnolin]

I am buying a royall 6300 wood boiler and a 1000 gallon storage tank. I will have 3500 sqft of radiant heat.
I am wondering about the in the sizing of the circulater how many gallons a minute in need to keep up with the boiler if it is running wide open. it is a 300000 btu with around 100 gallons in the boiler.
Any help would be appreciated

 

[Bob Rohr]

lets say the boiler operates at around a 70% efficiency, X 300,000 = 210,000 BTU/ hr to transfer from boiler to tank. Running a typical 20 temperature difference you need to pump 21 gallons per minute.

You will also want a temperature protection device installed to protect the boiler from extended cold return temperatures. Either a 3 way valve, or a unit with valve and pump in one module.

On the distribution side you will also need a mixing valve or device to provide the required temperature to the radiant. You will need two pumps, one for the boiler loop, one for the distribution, both sized to the load they will be moving.

 

[JP11]

I have a 60kw boiler.. 250k BTU. I use a Taco 0011.. which runs about 25gpm with my 1.5 inch piping to storage. It's a very short run, maybe 25 feet of pipe one way.

Just as a WAG. you really should do the head calculations and get the right pump. The boiler won't do you any good if you can't get the heat out of it into your storage.

JP