14
The thermostat(s) on the immersion heater(s) should be adjusted to trip at
60°C. This is the ideal temperature to prolong element life in hard water
areas. Scale on the sheath builds up more rapidly at temperatures above
this causing the element to overheat and premature failure can occur. Higher
temperatures without additional controls would result in scalding.
In addition to the thermostat the thermal cut-out will switch power off to the
element should the thermostat malfunction, causing an excessive rise in
water temperature. The thermal cut-out can be reset manually after the fault
has been corrected.
THERMAL
CUT-OUT
L2
N
L1
N
THERMOSTAT
DAY ELEMENT
3 kW 240V~
NIGHT ELEMENT
3 kW 240V~
ECONOMY 7
THERMAL
CUT-OUT
THERMOSTAT
THERMAL
CUT-OUT
L1
N
THERMOSTAT
ELEMENT
3 kW
240V~
Single Element
2.11
E
LECTRICAL
D
IAGRAM
Should the Economy 7 system not to be used, a separate 13 amp supply to
each element will be required. Through a double pole fused isolating switch
having a contact gap of at least 3mm on each pole.The immersion heater
shall be installed with 85°C rubber insulated hofr-sheathed flexible cords
complying with Table 8 of BS 6141: 1991. Make the connection(s) to the
immersion heater(s) as per F
IG
. 2.12 and F
IG
. 2.13. For High Capacity 500
litre models consult the wiring diagram on the reverse of the inspection
panel.
F
IG
. 2.12
F
IG
. 2.13
Summary of Contents for Contract STI 300 indirect
Page 23: ...23 NOTES ...
