![plumbing - Can someone explain to me how this hot water recirculating system works? - Home Improvement Stack Exchange plumbing - Can someone explain to me how this hot water recirculating system works? - Home Improvement Stack Exchange](https://i.stack.imgur.com/FB3Xy.jpg)
plumbing - Can someone explain to me how this hot water recirculating system works? - Home Improvement Stack Exchange
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Grundfos 99452459 (old part number 595916) UP15-10SU7P/LC Instant Hot Water Comfort Recirculation System 9H with NEW Digital Timer - Amazon.com
![Grundfos UP15-10SU7P TLC 3/4 in. NPT 115-Volt Comfort Hot Water Recirculation Pump 595916 - The Home Depot Grundfos UP15-10SU7P TLC 3/4 in. NPT 115-Volt Comfort Hot Water Recirculation Pump 595916 - The Home Depot](https://images.thdstatic.com/productImages/1eddd1c3-e18d-4a6f-845b-bf3acc74fcd0/svn/grundfos-hvac-accessories-595916-44_600.jpg)
Grundfos UP15-10SU7P TLC 3/4 in. NPT 115-Volt Comfort Hot Water Recirculation Pump 595916 - The Home Depot
![GRUNDFOS 98420224, UP 10-16 APMBU/LC, 115V, DIGITAL TIMER PUMP, W/ AUTO ADAPT AND LINE CORD, 1-1/4 INCH UNION » Cedars HVAC GRUNDFOS 98420224, UP 10-16 APMBU/LC, 115V, DIGITAL TIMER PUMP, W/ AUTO ADAPT AND LINE CORD, 1-1/4 INCH UNION » Cedars HVAC](https://cedarshvac.com/wp-content/uploads/2022/07/98420224-2-jpg.webp)
GRUNDFOS 98420224, UP 10-16 APMBU/LC, 115V, DIGITAL TIMER PUMP, W/ AUTO ADAPT AND LINE CORD, 1-1/4 INCH UNION » Cedars HVAC
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Grundfos 98420224 UP 10-16 A PM BU/LC Comfort PM AutoAdapt Recirculation Pump: Amazon.com: Tools & Home Improvement
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Grundfos Comfort UP 10-16 Hot Water Recirculating Pump w/ Digital Timer, 1-1/4" Union - PEXhouse.com
![Grundfos ALPHA 15-55 HWR-D Hot Water Recirculation Pump w/ Cord, Bypass & Isolation Valves – 99793173 Grundfos ALPHA 15-55 HWR-D Hot Water Recirculation Pump w/ Cord, Bypass & Isolation Valves – 99793173](https://images4.plumbersstock.com/product/500/500/920084-GyApX1.webp)