Operation Manual

thermostat (disjunction of the controlling circuit relay and heating bars) and thus the boiler shut-down occur

when the temperature reaches 105°C. Shall the emergency thermostat become disconnected, the boiler can be

only put back into operation by an authorized service engineer. Another protection of the boiler is assured by a

pressure switch which disengages the control circuit when the heating system water pressure decreases (when

there is not enough water in the heating system). When the system becomes replenished with water, the boiler

automatically relaunches operation. Proper deaeration of the heating system must be assured prior to launching

and also during boiler operation. The heating system bleeding is partially ensured by the automatic vent valve

which is placed at the outlet of heating water from the boiler body.

♦ Selected important characteristics and merits of THERM- EL electric boilers:

• top microprocessor control

• very quiet operation (switch power relay of the heating bodies)

• state-of-the-art design

• ergonomic, interactive control

• smooth regulation – 2.5 kW regulation step (5 kW with the higher performance series)

• service-adjustable pump deceleration

• protection of the pump against particulate build-up

• PID regulation

• anti-freeze protection

• DHW heating option (terminals for an external three-way valve, NTC temperature sensor or a storage tank thermostat)

• optional connection of an external NTC sensor (integrated equitherm regulation)

• connection of an NTC temperature room sensor (automatic controlling system as a room regulator)

• integrated safety switch contactor for all output phases

• possibility of an intelligent cascade boiler connection format (up to 32 boilers – with smooth output modulation)

• optional external control by means of GSM (external modem necessary)

• optional connection of an external regulator with OpenTherm communication

• balanced loading of the heating bars and bodies

• power relays do not form part of the processor board printed circuits (easy servicing and replacement). Special relays with

integrated fastons were used, i.e. high currents do not flow through printed circuits.

• boiler start system functioning on the basis of a mass remote control (MRC)

• external control of energy input (relief relay)

• soft start

• integrated Grundfos UPS 15/60 pump

• integrated 7 l expansion vessel (with the lower performance series)

• integrated safety valve

• automatic bleeding

• digital heating water pressure sensor (fitted with all types)

• auto-diagnostics, unequivocal service notification of defects

• optional boiler parameter adjustment (rich service menu)

• three-digit display (displays selected temperatures, pressure, output, error messages etc.)

• further 7 LEDs for unequivocal signalling of the operational conditions

• option of a default setting (immediate change of operation into the factory settings mode)