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[muffin]

I would like to redo my setup a bit to optimize it.  I think my current configuration is poor.  Here are my loops:

The boiler is pretty much level with the house and about 50' away.  My line are all on the main floor so maybe +/-6' from the boiler port height differential.  Everything is run in 1" pex.

Main loop from the boiler to the house is about 50' and just loops back.
1st loop is only 10' and supplies the pool water heater.  I have been told to try for at least 15-20GPM on this exchanger for good performance.  Tubes in shell style.
2nd loop is about 25' and has a 30 plate exchanger for my DWH (with bypass valve) and then a 3-way to either loop back or supply my pool room heat exchanger (water-air)
3rd loop is 250' and supplies two 3-ways that either divert or supply my two house exchangers (both water-air)

I currently have a:
taco 009-BF5-J
taco 007-F5
grundfos UPS26-99 3 speed.

Would love to use these pumps if possible but realize I probably need to buy at least one more as I think none of these are adequate as the main supply line pump.  I was thinking the taco 9 would be good for the 2nd loop as I should not need a lot of flow.  Perhaps the taco 7 for the 3rd loop figuring I have a long run to drive and don't need that much flow.  And finally the grundfos on the 1st probably on the middle speed.  Thinking I need something in the 50GPM range for the main loop.  Any suggestions?

Thanks

[hondaracer2oo4]

Don't have a lot of time to type and will reply more later but 8 gpm is the max efficient flow through 1 inch pex.

[RSI]

Is the main loop 50' each way or round trip?
Are all the other loops feeding off it? Are they connected with close tees or some other way?

Does the main loop have a pump or do they others just pull out of it?

Going by what I think you have, I would put the 007 on the pool exchanger, the 009 on the 250' run to the two heat exchangers, the 26-99 on the main loop and get a 15-58 for the DHW loop.

That may change though depending on how you actually have it setup. I really doubt you will get anywhere close to 50 GPM unless you replace the main loop with much larger pipe. You shouldn't need that flow anyway though. Your boiler most likely can't put out enough BTU's to keep up with a heat load that would require that flow rate.

[muffin]

Is the main loop 50' each way or round trip?
Are all the other loops feeding off it? Are they connected with close tees or some other way?

Does the main loop have a pump or do they others just pull out of it?

Going by what I think you have, I would put the 007 on the pool exchanger, the 009 on the 250' run to the two heat exchangers, the 26-99 on the main loop and get a 15-58 for the DHW loop.

That may change though depending on how you actually have it setup. I really doubt you will get anywhere close to 50 GPM unless you replace the main loop with much larger pipe. You shouldn't need that flow anyway though. Your boiler most likely can't put out enough BTU's to keep up with a heat load that would require that flow rate.

Main loop is 50' each way.  The other loops will be connected off it with close tees.  So what are you targeting for the water-air exchangers (GPM)?  I would assume you would run the 26-99 in high and the 15-58 on medium or something.

[hondaracer2oo4]

Do yourself a big favor and read this http://www.taco-hvac.com/uploads/FileLibrary/SelectingCirculators.pdf

Great reading for anyone that wants to do things right.

[Roger2561]

Do yourself a big favor and read this http://www.taco-hvac.com/uploads/FileLibrary/SelectingCirculators.pdf

Great reading for anyone that wants to do things right.

honda - Thanks for the link.  That's a lot of information in few pages.  My home printer has died so when I get back to work I'll print it for future reference.  Roger 

[RSI]

Is the main loop 50' each way or round trip?
Are all the other loops feeding off it? Are they connected with close tees or some other way?

Does the main loop have a pump or do they others just pull out of it?

Going by what I think you have, I would put the 007 on the pool exchanger, the 009 on the 250' run to the two heat exchangers, the 26-99 on the main loop and get a 15-58 for the DHW loop.

That may change though depending on how you actually have it setup. I really doubt you will get anywhere close to 50 GPM unless you replace the main loop with much larger pipe. You shouldn't need that flow anyway though. Your boiler most likely can't put out enough BTU's to keep up with a heat load that would require that flow rate.

Main loop is 50' each way.  The other loops will be connected off it with close tees.  So what are you targeting for the water-air exchangers (GPM)?  I would assume you would run the 26-99 in high and the 15-58 on medium or something.

I just looked up the ratings and you will most likely not be able to get more than in the 12-15 GPM range on the main loop. The 26-99 would be on the low end of that and a larger pump could get you to the top.

If you really need the high flow rates you mentioned, I would replace the main loop with 1-1/2" pex.

[Sprinter]

Honda that's a great link at Taco, and lots more info too. I think that should be a must read since a lot of owners are DIY and that info sure would cure a lot of problems.
What pumps are in each loop now? What are the delta T's for each zone? That will help you determine where you have to go. With unknown systems or zones that can't be calculated for what ever reason ( pipes buried behind walls,etc) I'll stick a VDT bumble bee pump or 3 speed grundfos in there and monitor what speed gives me the proper delta T the zone needs.
Back to the 1" S&R lines, they will only flow so many gpms, and the Taco site and or its flow pro videos will show this too.
50 GPM would eat the boiler and any metal fittings in the loop in short order. That would be a full water exchange in just a couple minutes even in a huge boiler. There is a reason the pipes are always oversized. Can't think of it the same as your potable water system.

[muffin]

The ports on he boiler are only 1" though.  So would running 1 1/2" really help?  There is a second set of ports.  Seems like the better option would be to run a second main loop.  Maybe dedicate that to the pool water heater since it needs the high flow rate?  What do you all think.

[ITO]

 Honda, that's a great Taco link, for me that's what it's all about, learning what size rather than just being told what pump you need. Thanks that's a keeper.

[hondaracer2oo4]

It really is great info. I found the when I was trying to size my system piping and pump after calling some dealers and they would just say use such and such because it's worked for me in the past. That obviously wasn't the righ answer. I got my delta t within 2 degrees of my goal using that taco guide.

[RSI]

The ports on he boiler are only 1" though.  So would running 1 1/2" really help?  There is a second set of ports.  Seems like the better option would be to run a second main loop.  Maybe dedicate that to the pool water heater since it needs the high flow rate?  What do you all think.

Yes, running 1-1/2" pex to a 1" fitting is not a problem. The small diameter long length is the flow killer. 1-1/2" pex is about 1-1/4" actual ID and the insert fittings are probably almost as small inside as a 1" pipe thread fitting.

[Sprinter]

If you know how many gpms your device needs, say 6 you could actually have a half inch hole on a fitting, and it will work. It will increase velocity at the bottleneck via the bournoule principal. So not something you want to do on a hydraulic separator or buffer tank.

It doesn't matter that the holes on the boiler are 1", if designed right this will tell you how many gpms it should flow max. On the headers larger pipe is used to slow down velocity , decrease noise, decrease pipe erosion and maintain separation. If you know gas pipe,,,,,NG and LP they. Work by volume not pressure, the pipe is always several times larger than what the appliance needs.

As for the pool, what does the specs on the HE say? How many gpms , delta T and supply temp. The higher the temp the less head you have also. So a 009 will flow more GPM @ 180 than it will at 160. This is also explained at Taco and grundfos site.

[muffin]

Since I am redoing all my piping, would I be better to make a loop of my main line and use closely spaced tees, or just buy two manifolds (one for supply and one for return)?  Just noticed some of the manifolds look kind of nice and have flow meters/check valves built into them.  I was also considering splitting the two house exchanges into their own loops so I can get rid of the 3-way valves.  They seems to start leaking to the closed side after about a year of operation anyways.

[LittleJohn]

Upsizing pex might not directly help increase GPM, but it would probably decrease head press so pump can push more GPM.

You only have to worry about erosion if fuild velocities are above 8ft/s (with metal pipes typically Cu), shows up as pin hole leaks several inches after an elbow or bend in piping.  For 1" PEX @ 8ft/s - you are looking at about 14 GPM