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[concordprof]

I'm currently struggling to get a sufficient burn from my owb (cb 4040). Currently the wood is a mixture of seasoned and green, so I'm hoping that this problem will take care of itself next year when I can burn seasoned wood. However, in reading another thread it got me thinking about the size of my circulating pump on my owb.

My stove is 45' from my house. The line comes into my basement, over about 20', up to my attic, and over another 30ft.

 I am unsure what size the pump is on the current model (I'm assuming just a standard pump for the 4030). Any help will be greatly appreciated.

[ITO]

 Take the numbers off your existing pump and you will get better info, it's hard to guess with so many pumps out there. Do you have gauges so you can tell what temps you have supply and return at your house? Green wood is not ideal, can you mix it with some drier stuff?

[LittleJohn]

Also, what size S&R are you running, and what kind of accessories (HXs, fan coils) are you feeding.  All this information helps you do the math to figure out where you are at approzimately for required flow and head loss

[concordprof]

I'm gonna check on the current pump size in the morning. I'm sure it is the standard that comes on the 4030. I've been considering purchasing a wireless meat thermometer to gauge toms and alert me before the stove drops too low.

My supply and return are 1"pex that is feeding one heat exchanger. I'm hoping to add another heat exchanger for the basement and set the stat down to 65.

Thanks

[RSI]

An easy way to check if the flow is way too low is turn on blower (and DHW if you have a plate) and grab a hold of the return line. If it is just warm you need more flow. It is normal to be able to tell the difference between the supply and return but if you have the boiler at 180 you shouldn't be able to keep your hand on the return for more that 5-10 seconds.

How high is the highest point in the system above the top of the OWB?

[concordprof]

Probably about 15 feet above it.

[concordprof]

Here is the current pump that is on the stove

http://www.amazon.com/Taco-009-F5-Single-Phase-Circulating/dp/B000LDFNAS

[Sprinter]

200' of 1" pex =5.02'HL @ 7gpm + HE and any other equipment HL.
 The 009 does 8.6gpm @ 10' of head. It has a very steep pump curve, but only 10gpm max. When running your boiler has to put out 70,000btu to keep the water temp from dropping.
At 7gpm it does a full water exchange in 20 minutes.

First thing I would do is measure your delta T at the HE. You can also reduce flow IF you have too much by partially closing a valve. It acts just like a balancing valve.
Another option if you understand outdoor reset controls. Is to replace the 009 with a variable delta T circulator. It will maintain a temperature differential that you set. And on colder days the house will pull more btu out, the pump senses this and adjust for it. So on a mild day you might see 20 hour burn times, and 4 hour burns on -10 days for example. The delta T circ will move the btuz the HE needs. Not to mention they use 10-35% of electricity of a fixed speed circ.

[Scott7m]

200' of 1" pex =5.02'HL @ 7gpm + HE and any other equipment HL.
 The 009 does 8.6gpm @ 10' of head. It has a very steep pump curve, but only 10gpm max. When running your boiler has to put out 70,000btu to keep the water temp from dropping.
At 7gpm it does a full water exchange in 20 minutes.

First thing I would do is measure your delta T at the HE. You can also reduce flow IF you have too much by partially closing a valve. It acts just like a balancing valve.
Another option if you understand outdoor reset controls. Is to replace the 009 with a variable delta T circulator. It will maintain a temperature differential that you set. And on colder days the house will pull more btu out, the pump senses this and adjust for it. So on a mild day you might see 20 hour burn times, and 4 hour burns on -10 days for example. The delta T circ will move the btuz the HE needs. Not to mention they use 10-35% of electricity of a fixed speed circ.

Are there any pumps out there right now comparable to the 011 or similar that use delta t sensors?

When I got mine the largest I could find was an 008 eqivealent.  Which is barely big enough.  My pump runs on 11 eatt most of the time and jumps to 35-40 when the heat is being called for

[Sprinter]

http://www.taco-hvac.com/uploads/FileLibrary/100-68.pdf

http://www.taco-hvac.com/en/products/Variable%20Speed%20Delta%20T%20%2200%22%3Csup%3E%26reg%3B%3C/sup%3E%20Circulators/products.html?current_category=372

http://www.pexsupply.com/Taco-Cast-Iron-Pumps-289000

If your talking about the Bumblebee, at start up it ramps up to full speed in the de mode to get an accurate reading of the whole loop. After a min or 2 it makes adjustments.  The thing I found is to have both sensors on the same material, not one on steel and other on pex or copper for example. It still works , but the target DT actual can be different than what the sensors see.

[Scott7m]

Yea I have my sensors under some pipe insulation on the supply and return at the back of the stove. Its done a good job all winter ramping up and down just as it should. 

Im adding a loop using a close t set up off of my main loop under the home to feed my garage.  I think when I do that im going to go ahead and install logstor all the way to the shop, ill have 2 pumps but one will be on demand