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Reduce Hot Water Demand

Nearly all offices have hot water available for hand washing, general kitchen use and in some cases for showering. There are plenty of ways of reducing demand for hot water:

  • Assess layout & design
  • Don’t use it
  • Make sure temperature is adequate but not too high (if storing hot water, like a normal cylinder, it needs to be a minimum of 60°C to minimise the risk of Legionella)
  • Install a mixer valve to reduce the temperature of the water at the tap (also a good safety feature)
  • Use it wisely

Assess Layout & Design

  • Assess the use of isolated outlets (e.g. sinks) to see if installing a hot water heater close to the point of use will both improve the services and be more efficient.
  • Often hot water temperatures are set at over 700C. Set the temperature to around 60-65 0C
  • Check a Watermark ‘A’ grade label, storage water heaters that do not have one are less efficient.
  • Showers use the most hot water, assess how much water is used and consider installing a low flow showerhead.
  • Installing a mixer valve by the hot water cylinder mixes cold water in with the hot, reducing the temperature to around 500C.
  • Insulate hot water pipes between the cylinder and the tap to reduce heat loss.

Don’t use it

  • Use cold water for rinsing hands/ dishes (keep hot water available for to health & safety)

Use it wisely

  • Ensure pipes and cylinders are insulated to reduce heat loss.
  • If dishwasher has heating elements make sure the incoming water supply is cold (unless you have gas fired or solar hot water)
  • Always do full dishwasher loads
  • Service gas water heater annually to ensure safety and efficiency.

Use Alternative Energy Sources

  • Solar water heaters can supplement electricity
  • Heat pumps, which use the sun and a compressor, can heat water far more efficiently than conventional heaters.

(See www.eeca.govt.nz for renewable energy information)

Conserve Water

Maintain your system