Controller interface and system for controlling a heating system

Abstract

A controller interface (B 12 ) between a hot water tank controller (B 13 ) and a heat pump controller (B 2 ) in a heating system is provided. The controller interface (B 12 ) comprises a response module configured to receive, from the hot water tank controller (B 13 ), a first signal indicative of a temperature. The response module provides a response signal based on the first signal and a temperature response characteristic and communicates the response signal to the heat pump controller (B 2 ). The controller interface (B 12 ) enables interoperability of a heat pump controller (B 2 ) and a legacy hot water tank system and hot water tank controller (B 13 ).

1 . A controller interface for interfacing between a hot water tank controller and a heat pump controller, the controller interface comprising:
 a response module configured to:
 receive, from a hot water tank controller, a first input signal indicative of a temperature; 
 provide a response signal based on the first input signal and a temperature response characteristic; and 
 communicate the response signal to a heat pump controller. 
   
     
     
         2 . The controller interface of  claim 1  wherein the response module is an electrical circuit and an electrical property of the circuit is configured to vary in dependence on the first input signal and the temperature response characteristic. 
     
     
         3 . The controller interface of  claim 1  or  claim 2  wherein the temperature response characteristic is programmable, preferably via a user interface. 
     
     
         4 . The controller interface of any preceding claim wherein the temperature response characteristic comprises a temperature-resistance relationship profile. 
     
     
         5 . The controller interface of any preceding claim wherein the temperature-resistance relationship profile is modelled on a response of a temperature sensor associated with a heat pump. 
     
     
         6 . The controller interface of any preceding claim wherein the response signal is a resistance of a circuit at the response module. 
     
     
         7 . The controller interface of any preceding claim, wherein the response module comprises a relay and a pair of potentiometers. 
     
     
         8 . The controller interface of any preceding claim, wherein the response module comprises a plurality of fixed value resistors for connection of a subset to a relay. 
     
     
         9 . The controller interface of any preceding claim wherein the response module comprises a transistor configured to operate in dependence on the first input signal. 
     
     
         10 . The controller interface of any preceding claim wherein the response module is configured to vary the response signal between a number of discrete values, preferably between two values; or wherein the response module is configured to vary the response signal in a continuous range of values. 
     
     
         11 . The controller interface of any preceding claim further comprising an auxiliary heater control module configured to:
 receive, from the heat pump controller, a second input signal associated with an auxiliary heating requirement; and   communicate, to the hot water tank controller, an instruction to operate an auxiliary heater in response to the second input signal.   
     
     
         12 . The controller interface of  claim 11  wherein the auxiliary heater control module comprises a potentiometer and an analogue to digital converter. 
     
     
         13 . The controller interface of any preceding claim wherein the controller interface is configured to communicate with the hot water tank controller via a digital communication protocol or via analogue signals. 
     
     
         14 . The controller interface of any preceding claim wherein the response module is configured to communicate with the heat pump controller via a sensor cable of the heat pump controller. 
     
     
         15 . The controller interface of any preceding claim wherein the controller interface is further configured to receive a user hot water schedule and to vary the response signal based on the user hot water schedule. 
     
     
         16 . A hot water tank controller configured to provide a first input signal indicative of a temperature to the controller interface according to any preceding claim. 
     
     
         17 . A system for controlling a heating system comprising:
 the controller interface according to any of  claims 1  to  15 ; and   a hot water tank controller, optionally according to  claim 16 .   
     
     
         18 . The system of  claim 17  wherein the hot water tank controller is configured to receive temperature measurements from one or more temperature sensors, optionally wherein the hot water tank controller is configured to switch on an auxiliary heater. 
     
     
         19 . The system of  claim 17  or  claim 18  wherein the hot water tank controller is configured to receive a user hot water schedule and to vary the first input signal based on the user hot water schedule. 
     
     
         20 . The system of any of  claims 17  to  19  further comprising a heat pump controller configured to control a heat pump in dependence on the response signal received from the controller interface. 
     
     
         21 . A heating system comprising:
 the system for controlling a heating system of  claim 20 ;   a hot water tank optionally comprising one or more of:
 an auxiliary heater disposed within the hot water tank; and 
 a temperature sensor configured to measure a temperature of water in the hot water tank; and 
   a heat pump configured to heat water in the hot water tank via a heat exchanger.   
     
     
         22 . The heating system of  claim 21  further comprising a diverter valve for diverting fluid from the heat pump to or from the heat exchanger, wherein the diverter valve is arranged to energise a pump of the heat exchanger. 
     
     
         23 . A hot water tank comprising an inlet port and an outlet port arranged to receive a retrofit heat transfer module comprising a plate heat exchanger, wherein the inlet and the outlet are sealed for use in the absence of a retrofit heat transfer module. 
     
     
         24 . A heating system comprising:
 the hot water tank of  claim 23 ;   a retrofit heat transfer module comprising:
 a pump configured to draw water from hot water tank via the outlet port and return water to the tank via the inlet port; and, 
 a plate heat exchanger configured to heat water drawn from the second outlet. 
   
     
     
         25 . The heating system of  claim 24  further comprising a heat pump with a diverter valve for diverting fluid to the heat transfer module, wherein the pump is controlled in dependence on the diverter valve. 
     
     
         26 . The heating system of  claim 24  further comprising a hot water tank controller, wherein the pump is controlled in dependence on the hot water tank controller.