Detecting and reporting faults in solar thermal systems
OwnerMogens Lauritzeninventor
Life of this patent
Estimating the term…
Abstract
A control system and a method are disclosed for detecting and reporting a variety of faults in solar thermal systems. Detected and reported faults include a low fluid condition in a closed loop of a solar thermal system in a drain-back configuration, a pressure drop in a closed of a solar thermal system in a glycol configuration, a pressure drop in a potable water portion of a solar thermal system of either configuration. Additionally, systems and methods are disclosed for detecting and reporting power outages and heat exchanger scaling, both of which may be experienced by a solar thermal system.
Claims27
A system for controlling the operation of a solar thermal system in a drain-back configuration, the system comprising:
- a fluid level switch positioned to sense a fluid level within a closed loop of the system;
- a pressure transducer positioned to sense a pressure drop within the system;
- and
- a controller coupled to the fluid level switch and the pressure transducer and a network.
A system for controlling the operation of a solar thermal system in a drain-back configuration, the system comprising:
- a drain-back tank;
- a fluid level switch positioned within the drain-back tank to sense a fluid level within a closed loop of the system;
- a controller coupled to the fluid level switch and a network, the controller configured to turn off a pump within the closed loop and transmit an alert over the network in response to the fluid level switch indicating the fluid level being below a threshold.
A system for controlling the operation of a solar thermal system in a drain-back configuration, the system comprising:
- a pressure transducer positioned to sense a pressure drop within the system;
- a controller coupled to the pressure transducer and a network, the controller configured to, responsive to the pressure transducer indicating a pressure drop, turn off a pump within the system and transmit an alert over the network.
A system for controlling the operation of a solar thermal system in a glycol configuration, the system comprising:
- a first pressure transducer positioned to sense a pressure drop within a potable water portion of the system;
- a second pressure transducer positioned to sense a pressure drop within a closed loop of the system;
- a first temperature sensor positioned to sense a first temperature at a first location;
- a second temperature sensor positioned to sense a second temperature at a second location;
- a flowmeter positioned to sense a flow rate;
- and
- a controller coupled to the first pressure transducer and the second pressure transducer and the first temperature sensor and the second temperature sensor and the flowmeter and a network.
A system for controlling the operation of a solar thermal system in a glycol configuration, the system comprising:
- a first pressure transducer positioned to sense a pressure drop within a potable water portion of the system, the first pressure transducer coupled to a controller;
- a second pressure transducer positioned to sense a pressure drop within a closed loop of the system, the second pressure transducer coupled to the controller;
- the controller coupled to a network and configured to, responsive to the first pressure transducer indicating a pressure drop:
- turn off a first pump in the potable water portion;
- transmit an alert over the network;
- determine a risk of a glycol fluid within the closed loop overheating;
- calculate a delay based on the risk;
- and
- turn off a second pump in the closed loop after the delay.
A system for controlling the operation of a solar thermal system in a glycol configuration, the system comprising a controller coupled to a network, the controller configured to:
- detect a restart of the system;
- determine a duration that the system was without power;
- determine a risk of a glycol fluid overheating during the duration;
- and
- responsive to determining the risk as above a threshold, transmit an alert over the network.
A system for reporting scaling in a heat exchanger of a solar thermal system, the system comprising a controller coupled to a network and configured to:
- calculate a present solar thermal output for the system;
- compare the present solar thermal output to a previously calculated solar thermal output;
- and
- responsive to the difference between the present solar thermal output and the previously calculated solar thermal output exceeding a threshold, transmit an alert over the network.
A method for controlling the operation of a solar thermal system in a drain-back configuration, the method comprising:
- responsive to detecting that a fluid level within a closed loop of the system is below a threshold, turning off a pump within the closed loop;
- and
- transmitting an alert.
A method for controlling the operation of a solar thermal system in a drain-back configuration, the method comprising:
- responsive to detecting a pressure drop within the system, turning off a pump within the system;
- and
- transmitting an alert.
A method for controlling the operation of a solar thermal system in a glycol configuration, the method comprising:
- responsive to detecting a pressure drop within the system, determining a location of the pressure drop;
- responsive to determining the location as within a potable water portion of the system:
- turning off a first pump in the potable water portion;
- transmitting an alert;
- determining a risk of a glycol fluid within a closed loop overheating;
- calculating a delay based on the risk;
- and
- turning off a second pump in the closed loop after the delay.
A method for controlling the operation of a solar thermal system in a glycol configuration, the method comprising:
- responsive to detecting a restart of the system:
- determining a duration that the system was without power;
- determining a risk of a glycol fluid overheating during the duration;
- and
- responsive to determining the risk as above a threshold, transmitting an alert.
A method for reporting scaling in a heat exchanger of a solar thermal system, the method comprising:
- calculating a present solar thermal output for the system;
- comparing the present solar thermal output to a previously calculated solar thermal output;
- and
- responsive to the difference between the present solar thermal output and the previously calculated solar thermal output exceeding a threshold, transmitting an alert.
Dependencies are inferred from the claim text.