Oversink and Undersink Water Heater
- 10-
4.5
Water connections
The assembly of the safety valves must be done in conformity to the regulations in force. We recommend the integration
of a filter in the cold water supply pipes. The link pipes must be perfectly insulated according to the energy norms in order
to avoid heating dispersions.
We recommend that you install the equipment close to the main hot water draw off point, to prevent heat dispersions
along pipes, and if possible near a drain, for easier emptying and condensate discharge.
If the incoming mains static water pressure exceeds 5 bar a pressure reducing valve must be installed to protect the heater.
It should not be installed between the unit and the pressure relief valve and sufficient pipework distance should be allowed
for expansion.
WARNING:
Water
temperature over 50°C
flowing from the hot water
tap may cause serious burns.
Children, disabled and
elderly run a greater risk of
injury and therefore it is
advisable to use a
thermostatic mixing valve
connected to the water hot
water outlet
WARNING: Tundish should be installed away from electrical devices.
4.5.1
Building Regulation G3
The following text is reproduced from the Building Regulations.
It is included here for reference only.
Discharge pipes from safety devices
Discharge pipe D1
3.50
Safety devices such as
temperature relief valves
or
combined temperature and valves
(se paragraphs 3.13 or
3.18) should discharge either directly or by way of a manifold via a short length of metal pipe (D1) to a
tundish
.
3.51
The diameter of discharge pipe (D1) should be not less than the nominal outlet size of the
temperature relief valve
.
3.52
Where a manifold is used it should be sized to accept and discharge the total discharge from the discharge pipes
connected to it.
3.53
Where valves other than the
temperature and pressure relief valve
from a single unvented hot water system
discharge by way of the same manifold that is used by the safety devices, the manifold should be factory fitted as part of
the
hot water storage system unit
or package.
Tundish
3.54
The
tundish
should be vertical, located in the same space as the unvented
hot water storage system
and be fitted
as close as possible to, and lower than, the safety device, with no more than 600mm of pipe between the valve outlet and
the
tundish
(see Diagram1).
Note:
To comply with the Water Supply (Water Fittings) Regulations, the
tundish
should incorporate a suitable air gap.
