LTHW and MTHW: Understanding Applications and Temperature Ranges

Low Temperature Hot Water (LTHW) and Medium Temperature Hot Water (MTHW) are two distinct systems integral to various heating applications. Understanding their differences, applications, and temperature ranges is crucial for selecting the right system for specific heating needs.

LTHW (Low Temperature Hot Water)

LTHW Explained:

Low Temperature Hot Water systems operate within a temperature range typically spanning from 60°C to 93°C. This makes them ideal for applications where moderate heat is sufficient. LTHW systems are commonly employed in residential buildings, schools, offices, and other settings where standard space heating is required.


LTHW is commonly used for:

  • Space heating in residential buildings.
  • Heating in schools and offices.

MTHW (Medium Temperature Hot Water)

MTHW Explained:

Medium Temperature Hot Water systems, in contrast, are designed to handle higher temperature ranges, usually ranging from 93°C to 121°C. These systems are tailored for applications demanding elevated temperatures, often found in industrial processes and larger commercial spaces such as hospitals.


MTHW is commonly used for:

  • Industrial processes that require higher temperature levels.
  • Heating in facilities with larger spaces and specialised temperature needs.
  • Chemical processing applications.

Understanding the Temperature Range

The temperature range plays a pivotal role in determining the suitability of each system for specific applications.

LTHW Temperature Range (60°C to 93°C):

LTHW systems excel in providing moderate heat suitable for standard heating needs. This temperature range is effective for maintaining comfortable temperatures in residential spaces and smaller commercial buildings. The components of LTHW systems, such as pumps, valves, and heat exchangers, are optimised for efficient operation within this lower temperature range.

MTHW Temperature Range (93°C to 121°C):

MTHW systems are engineered to handle higher temperature requirements. This makes them indispensable for industrial processes and larger commercial spaces where elevated temperatures are necessary. The components of MTHW systems are designed to withstand and efficiently transfer heat at these higher levels.

In conclusion, the choice between LTHW and MTHW depends on the specific heating requirements of the intended application. LTHW is suitable for standard heating needs in residential and smaller commercial spaces, while MTHW is geared towards industrial processes and larger facilities demanding higher temperature hot water. Understanding these differences is essential for optimising heating systems to meet the unique demands of diverse applications.

If you have a temporary heating requirement for an application that uses LTHW or MTHW, call a member of our team today on 0800 464 7025.

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