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[RSI]

i think you have about 15 feet of head in the pipe of 160 feet. to get 8 gpm you would need (from the taco chart) an 0011 or 0013. this would put you about the middle of the pump curve (where you should be) and 8 GPM would give you (at 180 degree water) 80,000 btu per hour and that is likley  near what your original home furnace is (just a guess) you can find that info on the name plate somewhere.

depending where you are and what your winters are like you can size yoru pump for how many GPM you need

every GPM at 180 delivers 10,000 btu to your home in you want only 6 GPM you can look on a pump flow chart for 15 feet of head at 6 GPM  and aim to find that required GPM near the middle of the pumps flow chart (as stated before this head loss is only for the pipe not for inside the house or the loss at exchangers (that is a good reason to aim for the middle of the pumps flow chart or go up a foot or 2 of head

How did you come up with 15 feet of head at 8 gpm? Using this chart for 8 gpm you need to multiply the length by 0.140 then multiply by 2.307. My calculations come out to almost 52 feet of heat on 160'. Am I doing something wrong?
http://www.alliedpex.com/LITERATURES/PEX_Pressure_Drop_Table.pdf

[willieG]

How did you come up with 15 feet of head at 8 gpm? Using this chart for 8 gpm you need to multiply the length by 0.140 then multiply by 2.307. My calculations come out to almost 52 feet of heat on 160'. Am I doing something wrong?
http://www.alliedpex.com/LITERATURES/PEX_Pressure_Drop_Table.pdf
[/quote]

maybe i made the mistake..

[willieG]

How did you come up with 15 feet of head at 8 gpm? Using this chart for 8 gpm you need to multiply the length by 0.140 then multiply by 2.307. My calculations come out to almost 52 feet of heat on 160'. Am I doing something wrong?
http://www.alliedpex.com/LITERATURES/PEX_Pressure_Drop_Table.pdf

maybe i made the mistake..
[/quote]

you are absolutely right, my bad eyes i got in teh wrong line (iwas at 1 inch=.041)

i appologise deeply  slosh disregaurd my post

in fact i will delete it so not to confuse you

[willieG]

RSI thanks for catching my goof up

[willieG]

slosh, I have a H2 also and my loop is close to 500 feet going through 2 water to air heat ex. and I used 3/4 inch pex. This is a c/p of a post I made earlier on here

 "Thanks for the replys, I ask the question at .ctwoodfurnace.com/ and was told that the taco 013 would work but the Taco 2400-20-WB Wood Boiler Series, High Capacity Circulators was what he recommended. This is what I ordered so when it comes in I will let you know how it works.
Thanks
Bull "

It is working great and I use the loop in the OWB for my hot water

bull do you know how many GPM you are getting  the chart on the pump you say you are using only goes to 34 feet of head?

[slosh250]

Bull- Is that taco pump your using a dry rotor type pump or a wet? Would like to have a dry rotor like the armstrong E9 but havent really gotten any flows or anything on it. Think i may just do the loop with 1 connection at the owb or may get that in 1 piece, the shop isnt that important to heat but all my wood is free to me and very easy to get so i dont mind burning some extra.

[RSI]

slosh, I have a H2 also and my loop is close to 500 feet going through 2 water to air heat ex. and I used 3/4 inch pex. This is a c/p of a post I made earlier on here

 "Thanks for the replys, I ask the question at .ctwoodfurnace.com/ and was told that the taco 013 would work but the Taco 2400-20-WB Wood Boiler Series, High Capacity Circulators was what he recommended. This is what I ordered so when it comes in I will let you know how it works.
Thanks
Bull "

It is working great and I use the loop in the OWB for my hot water

bull do you know how many GPM you are getting  the chart on the pump you say you are using only goes to 34 feet of head?

Looks like a little over 2 gpm is all a taco 2400-20 could do on 500' of 3/4" pex
This is just using the calculations. I never tested any to see if it actually came out the same.

[RSI]

Bull- Is that taco pump your using a dry rotor type pump or a wet? Would like to have a dry rotor like the armstrong E9 but havent really gotten any flows or anything on it. Think i may just do the loop with 1 connection at the owb or may get that in 1 piece, the shop isnt that important to heat but all my wood is free to me and very easy to get so i dont mind burning some extra.

Bull's pump is a dry rotor.
If you didn't buy that pump off ebay you will spend less buying 1" pex than the difference in the pump prices to get one big enough. (an e9 is close to $300 but there are others closer to $200 that a similar)

If you go with 1" a Grundfos 15-58 will probably pump as much as the E9 would on the 3/4" and it will use less power. Also if the big pump dies you have to buy a $200+ replacement instead of around $100.

Also with the 1" pipe you have the option of putting the larger pump on and getting a lot more flow than would be possible with the 3/4"

[slosh250]

RSI- how did you know it was on ebay? You must have bought it because it was gone today. Anyways i think i will just run the 320ft loop and keep it simple, what are the dry rotor make and models that would be good for my application? I'll wait for a good priced  one on ebay so i'm in no hurry just want to have it all by the time of install. And what would a good pump be for the 160-180 ft pull on the dhw as i am probly just going to use the coil in the furnace for now. I'm tryin to at least get 4-5 years out of this setup and go to somthing bigger maybe an h4 or bigger in the future. Thanks RSI and willie and others for your patience with me and all your input i would really be lost without you guys

[RSI]

No, I didn't buy it. I found it right after you posted about it and was watching it. I would have bought it if I knew you weren't.
Other than people here, I have never heard of using cast iron pumps on DHW. I always use bronze.

There aren't really any small dry rotor pumps. A B&G PL30 is the smallest that I know of. An Armstrong E7 might be smaller but not sure. (I didn't look it up)

If you setup the DHW loop so the cold water has to travel to the coil in the boiler before going into the water heater tank then you can just use a small pump to recirculate and won't need it near as big. A Taco 005 or 006 will probably work.

[Bull]

Slosh, sorry but I have no idea of the numbers on head pressure that you asked about. I was to far into my setup before I ran across this site. I was told by some that my setup would not work according to the charts but I remembered back on my fire fighting training about how much pressure you loose per section of hose and how I connected enough together that I "should not" have any pressure but did and even checked it with a pitot tube so sometimes the numbers are not correct.
As for your DHW I don't use a pump. I run the cold to the H2 through the coil and back to the hot water heater just using the house pressure.

[Hydronix]

i think you have about 15 feet of head in the pipe of 160 feet. to get 8 gpm you would need (from the taco chart) an 0011 or 0013. this would put you about the middle of the pump curve (where you should be) and 8 GPM would give you (at 180 degree water) 80,000 btu per hour and that is likley  near what your original home furnace is (just a guess) you can find that info on the name plate somewhere.

depending where you are and what your winters are like you can size yoru pump for how many GPM you need

every GPM at 180 delivers 10,000 btu to your home in you want only 6 GPM you can look on a pump flow chart for 15 feet of head at 6 GPM  and aim to find that required GPM near the middle of the pumps flow chart (as stated before this head loss is only for the pipe not for inside the house or the loss at exchangers (that is a good reason to aim for the middle of the pumps flow chart or go up a foot or 2 of head

How did you come up with 15 feet of head at 8 gpm? Using this chart for 8 gpm you need to multiply the length by 0.140 then multiply by 2.307. My calculations come out to almost 52 feet of heat on 160'. Am I doing something wrong?
http://www.alliedpex.com/LITERATURES/PEX_Pressure_Drop_Table.pdf

Uh......... Gentlemen, you do know your using the wrong chart...right?  That is a different head loss calculation, it doesn't figure friction head loss as a rate of flow.  Combined it is called total dynamic head loss , And the more gpm you flow the head goes up exponentially. That chart is specifically for potable water supply lines ( toilets,faucets, etc)  from a plumbing code book. 10 gpm at 180* supplies 100,000 btu/hr which is big enuff to heat some big homes.  You need to look at a pump chart like this   
http://www.taco-hvac.com/uploads/FileLibrary/SelectingCirculators.pdf

But before you do that, you need to know your heat load, how many BTU's you need all together. This will give you how many gpms you will need to flow. Also in that chart you will be able to see how much a 3/4 line can actually supply and whether you need to go larger or not. There is a reason 007,15-58 pumps are the most popular sizes, since they can supply over 150kbtu/hr on the right sized pipe. But if you exceed 10' head loss that 007 wont pump squat. Hopefully this helps a little

[banjoman]

Help please, I need someone to do the calculations for my owb. Piping is 160' round trip using 1" regular pex and approx 4' of lift. I am going through a filter,  5x12 heat plate, and a 18x18 heat coil. Any suggestion for the pump I will need?
Thanks

[Scott7m]

That bell and gosset 36 would likely be a good choice