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Twelve white wall-mounted mechanical thermostats with push buttons

Emerson 1C21-101 Mechanical Cool Only HVAC Control 12 Pack

SKU CH-4HSB-DXWAB MPN 1C21-101

A 12-pack of mechanical, mercury-free thermostats for single-stage cooling systems with a 50-90°F range and snap-action contacts

  • Mounting styleWall Mount
  • Relay contactSimple
  • Certifications and standardsNot capable emitting RF energy
  • Product typeThermostat, instructions, mounting hardware, Manual, Push Bu
  • Size or dimensions1.29 in × 2.93 in × 3.79 in
  • Product colorWhite
  • Compatible with single-stage cooling only systems
  • Mercury-free mechanical design eliminates hazardous materials
  • Rugged snap-action contacts provide reliable switching
  • Fixed heat anticipator maintains consistent temperature control
  • 12-pack supplies multiple installations or replacements

12-Pack Mechanical Cool-Only Thermostat

The Emerson 1C21-101 is a low-voltage mechanical thermostat designed for single-stage cooling-only systems. Each unit uses rugged snap-action contacts, a fixed heat anticipator and a bimetal thermometer. The mercury-free design operates across a 50-90 degree F temperature range. This pack contains twelve thermostats with mounting hardware and instructions.

Suits basic cooling control, not heat or multi-stage

Homeowners and contractors needing simple, reliable cooling control for compatible single-stage systems will find this thermostat straightforward to install and operate. Buyers who require heating capability, multi-stage cooling control or programmable scheduling should look at alternative models that support those functions. The mechanical interface offers no digital display or smart-home connectivity.

Mounting hardware and instructions included

Each thermostat ships with the necessary mounting hardware and a printed manual, so installers can complete the job without sourcing separate parts. The bundled instructions guide wiring for low-voltage cool-only circuits. No additional software, batteries or accessories are supplied or required for basic operation.

How it compares

Measured against everything we stock in Heating & Cooling Controllers, at today’s prices. Recalculated every night.

Price $21.99
Cheaper than about 71% of the 1,762 comparable items (median $45.99).

Specifications

Product
Brand nameWhite-Rodgers, Copeland
Model name1C21-101
Part number01C21 101S1
Product typeThermostat, instructions, mounting hardware, Manual, Push Button
Product colorWhite
Size & build
Size or dimensions1.29 in × 2.93 in × 3.79 in
Mounting styleWall Mount
In the box
Number of items12 pack
Environment & compliance
Certifications and standardsNot capable emitting RF energy
More details
Relay contactSimple

Questions about this item

Do I need a low-voltage single-stage cooling system already installed for this 1C21-101 thermostat to work?

Yes, the 1C21-101 is designed for single-stage cool only systems that use low-voltage wiring.

Will the 1C21-101 thermostat replace an older mercury thermostat on the same two-wire cooling circuit?

This mercury-free mechanical thermostat uses snap-action contacts and a fixed heat anticipator, so it can replace an older mercury unit on a compatible low-voltage cooling circuit.

How can I confirm the 1C21-101 is operating correctly after mounting it on the wall?

Set the dial between 50 and 90 degrees F; the air conditioner should cycle on when the room temperature rises above the set point and shut off once it reaches that temperature.

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