I have a question on pump dynamics after speaking with a Taco rep about the pump I plan to use for a hot water recirculation system. More accurately it's going to be a cold water purge system as I really don't need to circulate hot water. I plan to use a Taco 006e3 pump which I selected because of the variable speed and low cost.
One of the things she told me is that since it will just be used to purge that I can run it at max speed. I asked if that might put too much pressure on the pipes (PEX) and her response was that it doesn't really add any pressure to the system. I didn't feel it was appropriate to pick her brain and educate me on fluid dynamics so I though it might be an appropriate question here and of interest to others.
The idea of running it at max speed is appealing to minimize the purge time. On the other hand I'm concerned about putting unnecessary pressure on the pex pipes and fittings especially if I wind up using multiple pumps for different zones of what is a large footprint single story house with a basement. If pressure truly isn't a practical issue this zoning approach would really work well. The kitchen is in a corner of the house all by itself with 1/2" PEX for the supply and return so the idea of using a pump that can deliver 4gpm at 12' of head is cause for some concern without understanding how that can be safe.
Here's the brochure on the pump if you'd like to see it. This pump is only $175 and at that cost it's cheaper and simpler to use a pump for each zone rather than create zones some other way and have to deal with balancing the flow.
http://apps.taco-hvac.com/uploads/FileLibrary/006e3_Circulator_100-143_GREEN.PDF
One of the things she told me is that since it will just be used to purge that I can run it at max speed. I asked if that might put too much pressure on the pipes (PEX) and her response was that it doesn't really add any pressure to the system. I didn't feel it was appropriate to pick her brain and educate me on fluid dynamics so I though it might be an appropriate question here and of interest to others.
The idea of running it at max speed is appealing to minimize the purge time. On the other hand I'm concerned about putting unnecessary pressure on the pex pipes and fittings especially if I wind up using multiple pumps for different zones of what is a large footprint single story house with a basement. If pressure truly isn't a practical issue this zoning approach would really work well. The kitchen is in a corner of the house all by itself with 1/2" PEX for the supply and return so the idea of using a pump that can deliver 4gpm at 12' of head is cause for some concern without understanding how that can be safe.
Here's the brochure on the pump if you'd like to see it. This pump is only $175 and at that cost it's cheaper and simpler to use a pump for each zone rather than create zones some other way and have to deal with balancing the flow.
http://apps.taco-hvac.com/uploads/FileLibrary/006e3_Circulator_100-143_GREEN.PDF
