摘要 |
The temperature regulating unit of a heating system (H) is combined with a cascade circuit (22, 25, 39), operating in stages and as a function of load, for switching a plurality of heat generators (1a, 1b, K) on and off. It is suitable for multi-stage heat-pump operation (1a, 1b) in a bivalent heating system having a boiler (K) for fossil fuels as auxiliary heat generator. An integrator (18) integrates a temperature difference ( DELTA theta ) between a desired and an actual value ( theta vs, theta vj) with respect to time (t). A first threshold value switch (23) influenced by the integral regulates in each case one of the heat generators (1a, 1b, K), as a function of the heat requirement, in on/off operation, or an actuator (6, 7) in a quasi-continuous fashion as a pulse generator (24). Via a second threshold value switch (22) with a higher threshold value, the same integral controls the load-dependent switching on and off of the heat generators. The regulation and control system is suitable for low-temperature heating installations with flat heating curves, and also prevents the short-term switching on and off of the regulated heat generators (1a, 1b, K) under limiting conditions. …<IMAGE>… |