Honeywell EN2H-0221GE51 R0808 service manual Example

Hydraulic Components SDC / DHC

Discharge control 2

The heating circuits are always supplied with energy from the heat generator. As long as the buffer contains sufficient energy, the heat generator will be heated via the buffer loading pump instead of the burner. If the energy in the buffer is not sufficient, the burner will be started.

NOTE If a heat generator disable is active (e.g. through external burner disabling via contact or cycle disable (solid fuel/solar)), this will only result in the suppression of the demand for the burner.

Buffer setpoint The buffer setpoint temperature is the temperature that the buffer temperature tank has to provide for supplying the connected heating circuits. It

corresponds to the highest demand value of these heating circuits.

Example:

Demand value MC1 = 45°C

Demand value MC2 = 55°C

Demand value hot water = 65°C

=> buffer setpoint temperature = 65°C

A required offset value (e.g. hot-water load temperature offset) has already been taken into consideration in the demand value of the heating circuits.

Buffer minimum When there is heat demand for the buffer tank from the heating temperature limit circuits or from hot water, this request will be maintained at least

to the minimum temperature limit. When the temperature drops below this limit, the buffer tank is recharged by the heat generator under the conditions of the buffer start-up protection.

Buffer tank maximum If the buffer tank temperature exceeds the set value of the buffer temperature limit tank maximum temperature limit, forced switch-off of the buffer

loading pump occurs. The excess heat is dissipated into the selected circuits (see forced dissipation). Forced dissipation is disabled and buffer operation is resumed when the temperature in the buffer tank drops more than 2 K under the set maximum temperature limit.

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