Expansion Discharge - ElectraStream BEL 130 User Manual

4-5

Expansion Discharge

AIR BREAK
DISCHARGE PIPE
Fig. 4-5a Tundish
4 4 4 4 4
WARNING
Scalding water and steam can be
blown out of the discharge pipe.
Position the discharge so that it is
not a hazard to property or people
(especially children).
Dischar Dischar Dischar Dischar Discharge pipes fr ge pipes from safety devices ge pipes fr ge pipes fr ge pipes fr om safety devices om safety devices om safety devices om safety devices
Dischar Dischar Discharge pipe D1 Dischar Dischar ge pipe D1 ge pipe D1 ge pipe D1 ge pipe D1
3.49 3.49 3.49 Each of the temperatur 3.49 3.49 temperatur temperatur temperature r e r e r e r e relief valves temperatur
temperatur temperatur temperatur temperatur temperature and pr e and pressur e and pr e and pr e and pr essure r e r e r e r e relief valves essur essur essur
3.17 should discharge either directly or by way of a manifold via
a short length of metal pipe (D1) to a tundish.
3.50 3.50 3.50 3.50 3.50 The diameter of discharge pipe (D1) should be not less
than the nominal outlet size of the temperatur
3.51 3.51 3.51 Where a manifold is used it should be sized to accept and
3.51 3.51
discharge the total discharge from the discharge pipes
connected to it.
3.52 3.52 3.52 Where valves other than the temperatur
3.52 3.52
r r r r r elief valve elief valve elief valve
elief valve from a single unvented hot water system discharge elief valve
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 storage system unit storage system unit or package. storage system unit storage system unit
T T T T T undish undish undish undish undish
3.53 3.53 tundish tundish
3.53 3.53 3.53 The tundish tundish tundish should be vertical, located in the same space
as the unvented hot water storage system hot water storage system hot water storage system hot water storage system hot water storage system and be fitted as close
as possible to, and lower than, the valve, with no more than
600mm of pipe between the valve outlet and the tundish
Diagram 1).
Note: Note: Note: Note: Note: To comply with the Water Supply (Water Fittings)
Regulations, the tundish tundish tundish should incorporate a suitable air gap. tundish
tundish
40
4-5.1 Tundish (supplied)
Normally the Electrastream cylinder is supplied with a TPR valve and PR valve (part of the
combination valve) fitted and plumbed to the Tundish.
Fig. 4-5b shows typical GAH expansion discharge arrangement for unvented cylinders.
The Tundish must be vertical and fitted within 500mm of the temperature and pressure
relief valve and must be located with the cylinder. The tundish must also be in a position
visible to the occupants, and positioned away from any electrical devices. The discharge
pipe from the tundish should terminate in a safe place where there is no risk to persons in
the vicinity of the discharge, and be made of metal.
The Tundish must not be located near or above electrical components, switches or
junction boxes.
4-5.2 Expansion Discharge - Self Sealing Valve
A Hepvo Self Sealing Valve enables alternative discharge arrangements to be used,
however its use and installation must be approved by the local building control. Refer to
G3 Regulation and valve supplier/manufacturers instructions for installation and servicing
requirements.
4-5.3 Expansion Discharge Pipe - To Gully
The discharge pipe from the Tundish must be installed to comply with Part G3 of the
Building Regulations (latest edition). The following text, and diagram 1 are reproduced
from G3 Building Regulations 2000 (as amended) Draft.
elief valves elief valves elief valves elief valves or combined combined combined combined combined
elief valves elief valves elief valves elief valves specified in 3.13 or
tundish. tundish. tundish.
tundish.
temperatur temperatur temperature r e r e r e r e relief valve. elief valve. elief valve. elief valve.
temperatur elief valve.
temperatur temperature and pr temperatur e and pressur e and pr e and pr essur essure e e e e essur
temperatur e and pr essur
hot water hot water
hot water hot water
tundish tundish (see tundish tundish
INST INST INSTALLA INST INST
3.54 Any discharge should be visible at the tundish 3.54 3.54 3.54 3.54
where discharges from safety devices may not be apparent, e.g.
in dwellings occupied by people with impaired vision or mobility,
consideration should be given to the installation of a suitable
safety device to warn when discharge takes place, e.g.
electronically operated.
Dischar Discharge pipe D2 Dischar ge pipe D2 ge pipe D2 ge pipe D2
Dischar Dischar ge pipe D2
3.55 The discharge pipe (D2) from the tundish 3.55 3.55
3.55 3.55
a. have a vertical section of pipe at least 300mm long below
the tundish tundish before any elbows or bends in the pipework tundish tundish tundish
(see Diagram 1); and
b. be installed with a continuous fall thereafter of at least 1 in
200.
3.56 The discharge pipe (D2) should be made of: 3.56 3.56 3.56 3.56
a. metal; or
b. other material that has been demonstrated to be capable
of safely withstanding temperatures of the water
discharged and is clearly and permanently marked to
identify the product and performance standard (e.g.) as
specified in the relevant part of BS 7291).
3.57 3.57
3.57 3.57 The discharge pipe D2 should be at least one pipe size 3.57
larger than the nominal outlet size of the safety device unless its
total equivalent hydraulic resistance exceeds that of a straight
ALLA ALLA ALLATION ALLA TION TION TION TION 4 4 4 4 4
tundish. In addition, tundish tundish tundish
tundish tundish tundish should:
tundish