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Wetback & Water Boosters for Solid Fuel Appliances


  • Reduced power consumption and lower your power account.
  • Availability of hot water during power cuts.
  • Recover more energy from the fuel burnt - less heat lost up the flue

Almost all solid fuel appliances can be fitted with a water heating device that will either boost or provide a majority of the households hot water requirements. However there are a number of factors which can affect the performance of these units. These range from :-

  • The quality and type of fuel burnt.
  • The number of hours per day the fire is operated.
  • The average air control setting.
  • The distance between the appliance and the hotwater cylinder.

Other factors that can affect the benefits to be gained are:-

  • The thermal insulation of the hotwater cylinder and pipes.
  • The control of the electrical element whilst the appliance is operating. (An electric switch with bi-metal switch control can be fitted to the flow pipe from the heating device. This senses the hot water from the appliance and switches out the electric circuit to eliminate both electric and heating device working at the same tim e.)
  • Sizing the hot water cylinder to the household hot water requirements.
  • Ensuring the overflow pipe is not running over i.e. pressure reducing valve fault.
  • Ensure hot water tap washers are sound.
  • The output rating of the water heating device installed i.e. low output heating device against a larger hot water cylinder.


A well balanced system, i.e. sufficient hot water storage matched to the correct water heating device against the household hot water draw off, can occasionally become over heated with the result that boiling water squirts from the vent pipe and a banging noise is heard from the flow pipe between the appliance and the cylinder.

If this effect is a common occurrence - material damage can occur i.e. cylinder joint leaks, pipe joint leaks, tap washer premature failure, as well as the high risk of personal injury from excessive hot water and needless to say the wastage of water.

If you experience this situation immediately reduce the output of the appliance by closing the air control. DO NOT fully open hot water taps to drain the hot water. The effect of this action is to reduce the ‘head’ in the vent pipe which in turn reduces the pressure within the cylinder with the result the water is likely to boil more vigorously. Partially opening a hot tap will lessen the drop in ‘head’ pressure and allow a flow of cold water to enter the heating device via the base of the hot water cylinder. In due course the cylinder temperature will lessen and the noises stop.



Current Building regulations require all new hot water systems to be fitted with a Tempering Valve. These are fitted to the outlet side of the cylinder and control the maximum hot water temperature to the taps by mixing cold water with the cylinder hot water. Existing systems can be retrofitted to provide this safety feature.

Highly Recommended

  • Match the heating device, appliance, cylinder size and expected water use.
  • Ensure there is a Tempering Valve installed.
  • Upgrade the cylinder size if experiencing frequent boiling.

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