Heat Pump Buffer Preheating to Prevent Low-Pressure Startup Failures
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing heat pump systems face challenges in quickly restarting after installation or a longer standstill, particularly due to low return temperatures that can lead to low condensing pressures, affecting compressor operation.
Innovation Solution
A heat pump system with an electrical heating device on the flow line that heats the buffer before startup, ensuring the heating circuit medium is not too cold, and a temperature sensor to manage the heating process, allowing for efficient startup and operation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of time
If the heat pump system is started immediately after installation or standstill, then the system can begin operation quickly, but the return temperature is too low causing low condensing pressure and unstable compressor operation
Solution Approach 1:
The electrical heating device preheats the heating circuit medium in the buffer before the heat pump starts operating, ensuring the return temperature is sufficient for stable compressor operation. This preliminary heating action eliminates the harmful effect of low return temperatures during startup.
2Reliability
If the electrical heating device heats the heating circuit medium in the buffer, then the return temperature increases improving compressor operation, but additional energy is consumed for preheating
Solution Approach 1:
The system performs preliminary heating of the buffer before heat pump operation, which consumes additional energy temporarily but ensures stable and efficient compressor operation during the main operating phase, preventing energy waste from unstable operation or shutdowns.
Solution Approach 2:
The buffer acts as an intermediary thermal storage element between the electrical heating device and the heat pump compressor. It absorbs the preheating energy and releases it gradually, decoupling the energy input from the compressor operation timing.
3Reliability
If the buffer volume is increased to store more heated medium for startup, then the preheating capability improves, but the system size and cost increase
Solution Approach 1:
The system changes the temperature parameter of the heating circuit medium in the buffer through electrical heating, rather than increasing buffer volume. By controlling temperature, the system achieves reliable startup capability with a compact buffer design.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enables rapid system readiness and stable compressor operation by preheating the buffer, ensuring a minimum pressure difference and quick system recovery after a standstill.
Implementation Method 1
heat is supplied to the heating circuit medium located in the buffer (4) by means of an electrical heating device (5)
Implementation Method 2
heat can be supplied to a heating circuit medium by means of a heat pump (1)
Data Source
AI summary
In a method for operating a heat pump system, heat can be supplied to a heating circuit medium using a heat pump; a heating circuit medium flows through a heating circuit; in a first operating mode of the heat pump system, heat is supplied to at least one heat sink located in the heating circuit between a flow line of the heating circuit and a return line of the heating circuit; in a second operating mode of the heat pump system, heat is supplied to a buffer located in the heating circuit between the flow line and the return line and in parallel with the at least one heat sink. In a third operating mode of the heat pump system, an electrical heating device is used to supply heat to the heating circuit medium located in the buffer in order to start the heat pump.