Grundfos UP15-42F Replacement

Verified specifications

Single-speed circulator: drop-in replacement for older Grundfos UP circulators. If the failed pump was a 3-speed UPS, the 3-speed models above are the closer match — the system was balanced around a speed setting.

Not the VS: the variable-speed UP15-42F/VS was discontinued in July 2021 — do not confuse it with this single-speed model. The ALPHA 15-58F is the current variable-speed path.

Confirming the right replacement

Before we quote, compare these fields on your failed pump's nameplate. If any of them differ, send us a photo of the nameplate and we'll match it exactly rather than guessing:

• Full model number — including the part number (e.g. B&G P/N) where one exists
• Voltage and phase
• System duty: flow (GPM), head (ft), and fluid — heating water vs. potable water matters
• Flange size and orientation for in-line replacements

Other Grundfos models

• More Grundfos modelsBrowse every Grundfos model page we quote
• Grundfos UPS15-58FC3-speed sibling with built-in flow check
• Grundfos ALPHA 15-58FECM variable-speed upgrade

Documented equivalent replacements

The motors below are published as replacements for this model in the cross-reference tables cited. We confirm the match against your nameplate before quoting:

Cross references via Grundfos-published cross reference documents (VersaFlo UPS/TP guide L-UP-TL-008 and the competitive 3-speed pump cross reference). Match flange size, head, and flow to your system before ordering.