Quickly match the right TOSOT mini split size for your space.

Quickly calculate supplemental refrigerant needed when copper lines exceed 25ft.

Answer a few questions about your project and receive instant product recommendations.

Room Details

Need a more precise recommendation?

View the detailed HVAC Proposal Calculator for a full system match.

Enter your room details and click Calculate to see recommendations

Calculation Rules:

  • Standard Length: 25 ft (Refill threshold)
  • Additional refrigerant required for portion exceeding 25ft
  • Formula: (Actual Length - 25) × Refill Rate

Recommendation:

We recommend refrigerant charge be verified by a qualified HVAC installer during installation.

TOSOT Refrigerant Calculator v2.3

Get Your Custom
HVAC Proposal

Answer a few questions about your project and receive instant product recommendations powered by our local rule engine — no internet connection required.

1. Who Are You?
2. Project Info
3. Spaces
4. Proposal
Step 1 of 4

Who Are You?

Step 2 of 4

Project Information

🔇Ultra-Quiet
⚡Max Efficiency
💰Budget Friendly
📱WiFi / Smart
❄️Cold Climate
🛠️Easy Install
🌿Energy Star
💧Dehumidify
Step 3 of 4

Define Your Spaces

Add each room or zone. The rule engine will calculate BTU requirements and match products accordingly.

HVAC Project Proposal

Project:
Area:
Zones:
Total BTU:

BTU Calculation Breakdown

Space Qty Area (sqft) Floor BTU/sqft Adjustment BTU Required

Project Summary

    Next Steps

    1

    Review the recommended systems above and confirm they match your installation preferences.

    2

    Copy the proposal below and email it to support@tosotdirect.com to request pricing and availability.

    3

    Ask about certified installer referrals in your region and current lead times.

    Proposal copied to clipboard!
    Paste it into an email to support@tosotdirect.com
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