Underfloor Heating Basics

Is it safe and environmentally friendly to use hardwood flooring with an underfloor heating system?

International standards set very strict requirements for the moisture content, thermal stability, and formaldehyde emission levels of hardwood flooring, ensuring compliance with environmental standards. The floor temperature in an underfloor heating system is generally ≤32°C, which is virtually the same as most indoor temperatures in summer. This temperature does not exceed the normal range of indoor temperature fluctuations, so it will not increase formaldehyde emissions from the flooring, nor is there any need to worry about warping caused by moisture loss.

What are the typical supply and return water temperatures for underfloor heating? What is the temperature difference between supply and return water?

Supply water temperature: 60–50°C; Return water temperature: 50–40°C. The temperature difference between supply and return water should not exceed 10°C.

26. Why should the underfloor heating supply water temperature not exceed 60°C? If the supply water temperature exceeds 60°C, it will affect the comfort and safety of the underfloor heating system and shorten the service life of the piping.

27. How should you handle a supply water temperature exceeding 60°C?

(1) Adjust the supply and return water flow rates using manual control of the heating system or smart thermostats.

(2) Use a mixing valve to reduce the temperature.

(3) Residential complexes with centralized heating should use a heat exchanger.

(4) For homes with independent heat sources, install a mixing tank. For underfloor heating-specific boilers, reduce the air damper opening.