APR 2018
5
Hot Water Energy Storage
Unvented Cylinders
GB & NI
Installation & Maintenance Instructions for an unvented
hot water cylinder with external thermal expansion
Notes:
The pressure reducing
valve, non-return valve
and expansion relief valve
are combined together in
the inlet control set.
*No balanced cold on
selected cylinders. Refer to
insert sheet for details.
On 120 – 180 litre sizes
there is no dedicated
secondary return boss
and the secondary return
circuit should be tee’d into
the cold feed pipe just
above the drain elbow.
Coil connections for
heat pump models are
positioned vertically, with
the top connection for
heat pump flow and the
bottom connection for
heat pump return.
Notes:
*No balanced cold on
selected cylinders. Refer to
insert sheet for details.
VERTICAL UNIT
HORIZONTAL UNIT
IMMERSION
HEATER
COLD
MAIN
ISOLATING
VALVE
PRESSURE
REDUCING
VALVE
NON
RETURN
VALVE
EXPANSION
RELIEF
VALVE
TUNDISH
TEMPERATURE
& PRESSURE
RELIEF VALVE
BALANCED
COLD
CONNECTION*
COLD
INLET VIA
DRAIN
NON
RETURN
VALVE
BRONZE
PUMP
SECONDARY RETURN CIRCUIT
( 210, 250 & 300 L SIZES )
DUAL
STAT
2 PORT
VALVE
BOILER
FLOW
BOILER
RETURN
HOT OUTLET
EXPANSION
VESSEL
WITH WALL
BRACKET
180L & 210L 1
3
/
4
” BSP Boss
250L & 300L - IMMERSION HEATER
CRADLE
IMMERSION
HEATER
TEMPERATURE
& PRESSURE
RELIEF VALVE
DUAL
STAT
BOILER FLOW
BOILER RETURN
HOT OUTLET
TUNDISH
COLD
MAIN
ISOLATING
VALVE
PRESSURE
REDUCING
VALVE
NON
RETURN
VALVE
EXPANSION
RELIEF
VALVE
BALANCED
COLD
CONNECTION*
EXPANSION
VESSEL
WITH WALL
BRACKET
DRAIN
NON
RETURN
VALVE
BRONZE
PUMP
SECONDARY RETURN CIRCUIT
( 210, 250 & 300 L SIZES )
2 PORT
VALVE