Hi, I’m new to the forum and have a question and hoping someone can help. I’m building a new house and am just getting ready to plumb in the hot and cold water lines. I’m using PEX and will use a manifold/homerun configuration for both the hot and cold side. The house is 80 feet long and my ensuite is at the opposite end from the mechanical room. I would like to put in a hot water recirc pump set up to a motion dectector. I can understand how these recirc pumps work if one used the trunk supply method but if one has 7 or 8 hot water lines all running to different fictures via the homerun method how does one hook up the pump? Do you only do one ficture and run a return line back from that ficture to the water heater? Can one do more than one fixture using the homerun method? Thanks to anyone who can help.
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Replies
If you want the "instant" hot water to all the fixtures in your distant bathroom, you'll have to run either hot and cold water trunk lines to that bathroom (could be 3/4" PEX) or a hot water trunk line and dedicated return line.
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Solar & Super-Insulated Healthy Homes
Edited 2/23/2008 11:09 pm ET by Riversong
The recirc. systems are really meant to be used with a standard trunk line style plumbing system. the manifold system you describe is not set up for the pump. with an 80 foot pipe run to the master bath you may want to look at a second manifold and recirc. pump to the master bath manifold or even a second (small 12 gallon Marathon brand electric) water heater in the master bath fed by a 3/4" hot water trunk from the main water heater (I'm assuming gas demand water heater) this would accomplish the quick and endless hot water at the master bath with out the pump.
Hope this is helpful.
M
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"You cannot work hard enough to make up for a sloppy estimate."
Thanks for your input ... makes perfect sense and a bit of what I was thinking. Never thought of putting a small tank close to the master suite but certaintly also makes perfect sense. Thanks again.
There are systems that use a pump at the tank and thermostatic bypass valve(s) at the fixture.
I think that you can have multiple bypass valves and make it work on a manafold system.
But probably not practical for that many connections.
.
A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
I have two Grundfos "comfort valves" set up with a singlepump on a centrally located water heater at my house and it works but wastes a lot of energy given the extended nature of my home (four buildings, three of which are connected by breezeways and share a single solar / Rinnai water heater) at least most of the energy I'm wasting is coming from the sun but it's not what I recommend for my clients any more. These days the Metlund D'mand system for re-circulating hot water or the remote tank system such as I recommended for this situation is what I'm doing. Be well.M------------------
"You cannot work hard enough to make up for a sloppy estimate."