My Client wants his hot water without a wait. (?) hot water loops, do they work? my bath is two levels up from the water heater, will a pumpless loop give me quick hot water 25 to 40 ft. away? Pumps waste energy but if a pumpless loop wont work, what about loops with valve switches that one programs to start the flow at given times.
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UltraCirc UCT-303-B
Integrated Circulation Pumps That Save You Time and Money
Features:
Pump Photo:
View Image
Technical Data:
Model
Volts
Cycle
Phase
Watts
Amps
Maximum. Pressure
Maximum Temperature
Weight (lbs.)
UCT-303-B
115
60
1
33
0.30
150 PSI
230F
2.5
UCT-303-B
230
60
1
33
0.15
150 PSI
230F
2.5
UCT-353-B
230
50
1
28
0.13
150 PSI
230F
2.5
Performance Curve:
View Image
Material of Wetted Parts:
Ordering Information:
Standard pump configuration includes brass inline housing,
concealed capacitor, and two 6 inch pigtails for hard wiring.
Options Available:
Copyright © 2004 Laing Thermotech, Inc.
All Rights Reserved
http://www.lainginc.com/
Igr,
Oh, yeah. "Pumpless" loops wotk real well, and with 2 levels height difference you will have nomproblems.
But.
There ain't no such thing as a free lunch.
The energy to pump the fluid in a pumpless system comes from heat loss. As the water in the return side loses heat, it becomes "heavier" than the hot side, pulling hot water up as the cold side falls.
Ya need a spring loaded check valve in the return side to prevent sucking the cold water up when the faucet is open.
Insulate both loops, except the first verticle foot at the top of the return loop. Run the faucet till you get hot water. Wait 30 minutes, then feel that uninsulated foot. If it's still hot, you're done. If not, strip the insul from another foot and repeat the whole procedure. Repeat as needed. With 2 stories of height, it'll probably work with just 1 foot uninsulated. You might need 3', but I doubt it.
The more uninsulated return loop, the more water you will pump. You gotta reheat all that water.
SamT
"will a pumpless loop give me quick hot water 25 to 40 ft. away? Pumps waste energy but if a pumpless loop wont work, what about loops with valve switches that one programs to start the flow at given times."
Sure, you can just use gravity. Though the pumped loops have the advantage of a timer and a thermostat for more precise control. Most of the energy lost with DHW recirc is not from the electric pump, but from heatloss in the loop. Properly insulating the loop can be a challenge in a retrofit situation.
DHW recirc is convenient, and it does save water.
Look into the Grundfos UP recirc. Also, they have these 'on demand' systems with switches to activate the recirc, like Metlund.
http://www.gothotwater.com/
http://www.grundfos.com/web/grfosweb.nsf/Webopslag/A01C1CEA7B738EE3412568DF00718F7A
This might help some.
http://www.redytemp.com/Hot_Water_Circulation_Systems/Hot-Water-Recirculation-System-Comparison.htm
http://www.redytemp.com/comfort_valve_vs_outlet_installl.htm
Two stories should be fine for a recirc loop. Run it to the farthest fixtures, as long as it's one that's used...no point wasting it on a utility sink. We have a thermosiphoning loop covering 2 stories and it works great. The supply lines are 3/4 pex, the recirc is 1/2" pex and they're insulated.