PEX Calculator Radiant Floor

Heat Transfer Formula:

\[ Q = U \times A \times \Delta T \]

Overall Heat Transfer Coefficient (U):

W/(m²·K)

Floor Area:

m²

Temperature Difference (ΔT):

Heat Transfer Rate (Q):

1. What is a Radiant Floor Heat Transfer Calculator?

Definition: This calculator estimates the heat transfer rate for radiant floor heating systems based on the floor area, heat transfer coefficient, and temperature difference.

Purpose: It helps HVAC professionals and homeowners design efficient radiant floor heating systems by calculating the required heat output.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ Q = U \times A \times \Delta T \]

Where:

\( Q \) — Heat transfer rate (Watts)
\( U \) — Overall heat transfer coefficient (W/(m²·K))
\( A \) — Floor area (m²)
\( \Delta T \) — Temperature difference between floor and room (Kelvin)

Explanation: The heat output is calculated by multiplying the heat transfer coefficient by the floor area and the desired temperature difference.

3. Importance of Heat Transfer Calculation

Details: Proper heat transfer estimation ensures comfortable room temperatures, energy efficiency, and correct sizing of heating system components.

4. Using the Calculator

Tips: Enter the U-value (default 0.5 W/(m²·K) for typical PEX systems), floor area in square meters, and desired temperature difference (default 10K). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What's a typical U-value for PEX radiant floors?
A: Most PEX systems have U-values between 0.4-0.6 W/(m²·K) depending on pipe spacing and floor construction.

Q2: How do I determine the temperature difference?
A: ΔT is the difference between floor surface temperature and desired room temperature (typically 5-15K).

Q3: What if my floor has different materials?
A: Adjust the U-value accordingly - tile has higher conductivity than wood, for example.

Q4: Does this account for heat loss?
A: No, this calculates heat output. For complete system design, consider heat loss calculations for the space.

Q5: How does this relate to PEX tubing requirements?
A: The heat transfer rate helps determine required water temperature and flow rate in the PEX tubing.