Description
Product Summary
The McDonnell & Miller 42S is a circulator pump from McDonnell & Miller, described by the manufacturer as: pump Controller/Low water cut off 129302. It replaces 42 129300.
A circulator pump moves heated or chilled water through a hydronic system. Circulators are matched by flow, head, horsepower, voltage, flange size and body material. Cast iron is used in closed heating loops; bronze or stainless steel is required for open and potable water systems. Replace a circulator that hums without pumping, leaks at the body or seals, runs hot or is noisy after air has been purged from the system.
Before you order, match 42S to the part number on the part you are replacing or in your equipment's repair parts list, and confirm the voltage, size and connections match your equipment. If you are not sure which part your equipment needs, call us at 1.888.509.3391 with the model and serial number and we will confirm it for you.
Key Features
- Genuine McDonnell & Miller part: Manufacturer part number 42S, factory new.
- Cross-reference: Replaces 42 129300.
- Part type: Circulator Pump.
- Ready to ship: In stock with live quantities shown on this page.
Frequently Asked Questions
Is this a genuine McDonnell & Miller part?
Yes. This is the McDonnell & Miller 42S, a factory-new circulator pump from McDonnell & Miller.
How do I make sure it fits my equipment?
Compare 42S with the part number printed on the part you are replacing or listed in your equipment's repair parts list, and confirm the voltage and connections match. If you are not sure, call us at 1.888.509.3391 with your model and serial number and we will confirm it.
What part numbers does the 42S replace?
The McDonnell & Miller 42S replaces 42 129300.
Can I use a cast iron circulator for domestic hot water?
No. Open systems that bring in fresh water need a bronze or stainless steel circulator to prevent corrosion.
Should a professional install this part?
Yes. Gas, electrical, hydronic and combustion components should be installed by a qualified technician who can test the system afterward and follow the codes that apply where you live.
