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13.
DHW heating
The THERM ELN boiler can be connected with an external indirect storage tank for DHW heating. In order
to ensure DHW heating, the control panel of the LEKCPU boiler
needs to be extended with the so called DHW
module. The module consists of a LEKBOD panel which is connected with the LEKCPU panel by means of
two cables (power and signal cable). The LEKBOD panel can be connected with the storage tank thermostat
contact by means of screw terminals and with a 3-way valve (230 Vst) by means of a cable with the 3-pin
RAST 5 connector. The LEKBOD panel is mounted on a DIN-rail next to the contactor and supply terminals.
Connection of the DHW module and servicing of the electrical system of the boiler may only be carried
out by authorized service companies!
The storage tank is heated by automatic adjustment of the 3-way valve. Operation with the DHW storage
tank is always subordinate to heating and the selected temperature is always maintained without any time limits
(except for the HDO signal). If the temperature in the storage tank drops below the setpoint, the 3-way valve in
the boiler system will be adjusted in the first place and the boiler water will be heating the external indirect
DHW storage tank.
♦
Sample wiring diagram of the ELN 8, 15* electric boiler with indirect storage tank OKH 100
NTR-HV
* For the given tank volume, a corresponding boiler type and output has been selected.
8, 15 ELN
