Rheem Lo Line Tank Sensor
If you are just replacing the tank sensor on your system, we recommend you check the sensor port or immersion sleeve for moisture. If there is moisture, the sensor port or immersion sleeve will need to be replaced. This is mostly a problem in the older stainless steel hot water tanks. The original sensor port develops pin holes because it is the weaker metal.
Sensors are not designed to be installed in water and the moisture gives them an inaccurate reading. If you find moisture, check the roof sensor and the circulation pump first before ordering a tank sensor. Just because the pump motor is running does not mean it is circulating water as it should. With some models of solar hot water systems, your best option may be replacing everything at once with a complete pump station. Please contact us if you have questions about this before you purchase this item.
It is important that tank sensors are not used as roof sensors. Tank sensors are normally made from PVC cable and not high temperature silicone cable. Tank sensors are generally only rated to 90 degrees, whereas roof sensors can be rated two to three times higher.
Not all sensors are the same. This is a common mistake because over the years some manufacturers changed controllers multiple times. The thermistor inside the sensor gives different resistance levels with temperature change and the controller uses the reading to calculate the differentials required to operate the circulating pump.
There are many different types of controllers that use different types of sensors. If you are unsure, email us a photo of your controller and we can guide you to the correct sensor.
Images of the solar hot water controllers and original sensors are included in the description of products to assist you to find the appropriate product for your system (controller is not included in sale price).
Solar Hot Water Parts has the complete solar hot water replacement range. We are continually extending our solar hot water spare parts catalogue to give you the best selection of solar hot water replacement parts to choose from.
We sell the widest range of spare parts to suit any solar hot water service, whether it be a flat plate panel or evacuated tube solar collector. The Solar Hot Water Parts range is now online and ready to order, with complete tech specs to ensure your seamless selection.
If you're unsure which part suits, simply contact us - click here
A solar monitor is located on the side of the solar control unit and houses a green and a red LED.
The green LED, marked “Solar”, indicates the current operational mode of the solar water heater and the red LED, marked “Attention”, indicates a fault mode.
The green LED will emit either a constant glow or a series of flashes, with a 2 second interval between each series.
The red LED will emit a series of flashes, with a 2 second interval between each series, only if there is a particular fault condition with the system.
The operational modes are:
Flashes Operational Modes
solid green (remains on) Standby mode
green slow pulse Standby mode (power on for less than 48 hours)
green rapid pulse Water circulating through collectors
3 x green Water circulating through collectors (power on for less than 48 hours)
no green (remains off) Power outage or call for service
If the power supply to the solar control unit is on and the green LED is off or the red LED is flashing, this indicates there may be a fault with the water heater. The red LED may emit up to six flashes in each series of flashes.
- If the system is in standby mode with the green LED emitting either a constant glow or slow pulsing flashes (circulator is off) and the solar storage tank is full of hot water, the red LED may simultaneously emit a constant glow if solar radiation is still being received by the solar collectors. This does not indicate a fault. The red LED will go out when the temperature in the solar collectors decreases.
- During periods of high solar radiation and the circulator activates after having been off (the green LED will emit either a rapid pulse or a series of three flashes), it is possible the red LED may simultaneously emit a rapid pulse for a period of up to ten (10) minutes. This does not indicate a fault.
- If the red LED continues to emit a rapid pulse for longer than ten (10) minutes, or emits a series of flashes, then count the number of flashes and phone Rheem Service or their nearest Accredited Service Agent to arrange for an inspection.