HVAC Defrost Mode Switching Using Backup Sensor Feedback
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
HVAC systems face performance issues when feedback from sensors becomes unavailable, leading to inefficient operation or suspension of conditioning processes, as they rely on specific sensor data to maintain optimal temperature and defrosting conditions.
Innovation Solution
The implementation of a controller that can switch to alternative defrost or conditioning modes using feedback from different sensors when primary sensor data is unavailable, ensuring continuous operation and maintaining desired performance by directing heated refrigerant to the outdoor coil based on alternative temperature measurements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the HVAC system operates in primary defrost mode using feedback from the first sensor, then the defrosting control precision is improved, but the system reliability deteriorates when the sensor feedback becomes unavailable
Solution Approach 1:
The patent introduces a second sensor as an intermediary backup when the first sensor fails. The controller switches to using feedback from the second sensor to maintain defrost mode operation, ensuring continuous system reliability even when primary measurement feedback is unavailable
Solution Approach 2:
The controller changes the measurement parameter source from the first sensor to the second sensor when feedback unavailability is detected. This parameter substitution allows the system to maintain defrosting control using alternative temperature feedback, resolving the contradiction between measurement precision and system reliability
2Object-affected harmful factors
If the HVAC system suspends operation when sensor feedback is unavailable, then the system safety is improved, but the productivity deteriorates due to operation suspension
Solution Approach 1:
The second sensor acts as a mediator that enables continued operation when the first sensor fails. By switching to alternative sensor feedback, the system maintains productivity without compromising safety, as the backup sensor provides sufficient information for safe defrost mode operation
Solution Approach 2:
The system uses its own redundant sensor resource to service itself during primary sensor failure. This self-service capability allows the HVAC system to maintain operation and productivity without external intervention, resolving the contradiction between safety and productivity
3Adaptability or versatility
If the HVAC system uses alternative defrost mode with second sensor feedback, then the system adaptability is improved, but the measurement precision deteriorates compared to primary sensor operation
Solution Approach 1:
The system prepares backup sensor capabilities in advance to cushion against primary sensor failure. The controller is pre-programmed to switch to alternative defrost mode using the second sensor, ensuring adaptability is maintained even if measurement precision is slightly reduced compared to primary sensor operation
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
This solution allows HVAC systems to maintain performance and avoid suspension by using alternative sensor feedback, ensuring the outdoor coil remains above a threshold temperature and the air flow is conditioned effectively even when primary sensor feedback is unavailable.
Implementation Method 1
place the air flow in a heat exchange relationship with a refrigerant to condition the air flow
Data Source
AI summary
Embodiments of the present disclosure are directed to a controller for a heating, ventilation, and/or air conditioning (HVAC) system. The controller is configured to operate in a first defrost mode or a second defrost mode, determine that feedback from a first sensor of the HVAC system is unavailable, receive feedback from a second sensor of the HVAC system, and operate the HVAC system in the second defrost mode instead of the first defrost mode in response to unavailability of the feedback from the first sensor and based on the feedback from the second sensor.