All water pipes must be adequately insulated to minimise energy waste during heat transfer.
Heat losses from pipes are proportionate to the temperature difference between the water inside and the surrounding temperature, so that in an ambient temperature of 20 ºC water at 60 ºC loses twice as much heat energy per metre of piping as water at 40 ºC. Reducing excessive water temperature is an effective measure to reduce heating energy demand. A water temperature of 40 ºC at the point of use is sufficient for guest bathrooms, and regulations in some countries restrict the maximum temperature of hot water in commercial and public buildings. Separate boiler systems should be installed for hot water and central heating systems to avoid overheating of hot water based on heating system temperature requirements. One universally applicable best practice measure is to ensure adequate thermal insulation of all hot water pipes.
It is imperative to refer to relevant national legislation on water system hygiene, particularly with respect to the minimisation of risk from Legionella bacteria. Usually, water systems above a specified capacity must be heated to at least 60 ºC, though this may be implemented periodically.
Environmental benefits
- Energy saving
Reduced costs
- 20 mm of insulation can reduce heat loss by almost 400 kWh per year for every metre of large diameter (5 cm) piping.