Description
Product Summary
The McDonnell & Miller 42S-HD is a switch from McDonnell & Miller, described by the manufacturer as: head mechanism for 42 with snap switch 129502. It replaces 42-HD.
This switch opens or closes a circuit in response to a door, temperature, pressure or other condition, allowing the equipment to run only when conditions are correct. Replace a switch that no longer changes state when it should or shows physical damage.
Before you order, match 42S-HD 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-HD, factory new.
- Cross-reference: Replaces 42-HD.
- Part type: Switch.
- 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-HD, a factory-new switch from McDonnell & Miller.
How do I make sure it fits my equipment?
Compare 42S-HD 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-HD replace?
The McDonnell & Miller 42S-HD replaces 42-HD.
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.
