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Mst04 - Mrcool Smart Thermostat - Mrcool

Brand: Mrcool
Part #: Mst04
$99.00
🏭 Ships Directly from Manufacturer This item ships straight from our trusted supplier — saving you time and keeping things moving fast.
* Unsure about this part? Submit a " Part Number Research " request for assistance.
Brand New Part
Eligible For Free Shipping! Cart Minimum $145
Manufacturer Warranty Included - More info
Return & Cancellation Policy - More info

Description / Mst04 - Mrcool Smart Thermostat - Mrcool

MrCool Mst04 Thermostat
MrCool • HVAC Equipment / Parts
Mst04MrCoolThermostat

Mst04 Thermostat MrCool MrCool Thermostat mini split Mrcool Smart Thermostat

The MrCool Mst04 is a MrCool thermostat for controlling the system Mrcool Smart Thermostat. Mounts on an interior wall and wires to the air handler or furnace control board.

⚠ Important Note

Disconnect power before servicing. Refrigerant-circuit work (condensers, coils, TXVs, linesets) must be performed by an EPA Section 608-certified technician improper handling of refrigerant is illegal and unsafe. Verify model and refrigerant type (e.g., R-410A vs. R-454B) before installing.

✗ Symptoms

  • ✗ System not responding to setpoint
  • ✗ Blank or faulty display
  • ✗ Erratic cycling

✓ What This Restores

  • ✓ Full cooling and heating performance
  • ✓ Restored efficiency and capacity
  • ✓ Reliable, quiet operation
  • ✓ Correct system control
  • ✓ Equipment back to spec

🔧 Installation Overview

  1. Disconnect power at the disconnect and confirm the system is de-energized before any work.
  2. For refrigerant-circuit parts, recover refrigerant per EPA rules this work should be done by an EPA-certified technician.
  3. Remove panels and the old component, noting wiring and line connections.
  4. Install the new MrCool component, reconnecting lines and wiring exactly as removed.
  5. Pressure-test, evacuate, and recharge as required, then restore power and verify operation.

📋 Specifications

Specifications
TypeThermostat
BrandMrCool

❓ Common Questions

What is the MrCool Mst04?

It's a MrCool thermostat a MrCool thermostat for controlling the system.

Will it work with my MrCool system?

Match the capacity, voltage, and refrigerant type to your existing system. Check the specs above, or send us your model and we'll confirm compatibility.

Do I need a professional to install it?

Refrigerant-circuit work requires an EPA-certified technician by law. Other connections may be DIY-friendly, but always disconnect power first.

Not sure this is the right part?

Send us your MrCool model number and our team will confirm the exact fit.

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