Maintenance
Note: It is best to service your system in the morning because all of the components will be cooler.
Components and water may be very hot.
Every 6 months:
Back Flush the Tank and Heat ExchangerRegardless of water quality, it is important to flush the system of minerals that will inevitably collect at the bottom of the tank and heat exchanger. These minerals will impede the flow of water and reduce your efficiencies. |
Check the Heat Transfer Fluid LevelSunward Heat Transfer Fluid is a food grade product and no other Heat Transfer Fluid should be used or you will void your warranty. |
Inspect the Mixing valveSolar heated water can get surprisingly hot, as the mixing valve tempers the very hot water down to a safe temperature before it enters your existing heater. It is important to make sure the valve is mixing water correctly. |
Back Flush the Tank and Heat ExchangerRegardless of water quality, it is important to flush the system of minerals that will inevitably collect at the bottom of the tank and heat exchanger. These minerals will impede the flow of water and drastically reduce your efficiencies. |
Instructions:
Back-Flush the Heat Exchanger:
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Back-Flush the Tank:- Remove the brass cap that is furthest from the heat exchanger and replace it with the female end of a hose (see figure 3) - Place the other end of the hose into a clean 5 gallon bucket, drain, or outside the home - Turn the Blue valve 90 degrees clockwise - Open the drain valve by turning the silver handle counter-clockwise (water will be forced out of the hose) - Let the water run until the cloudy water turns clear (typically requires 5-10 gallons) - Close the drain valve by turning back to its original position - Turn the Blue handle to the original position - Remove the hose
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Check The Heat Transfer Fluid Level:The pump must be turning in order to get an accurate reading - Open the heat exchanger lid - Slowly remove the Brass Cap that is attached to the fill tube by turning it counter clockwise (Note: system may be under pressure) - Insert the wooden dipstick all the way down inside the fill tube (the dipstick is typically tucked behind the insulation at the rear of the unit) - Remove the dipstick and read the level (Heat Transfer Fluid is a clear substance so the darker part of the dipstick is the easiest to read) - Heat Transfer Fluid level should be between 2 and 8 inches from the bottom of the stick while the pump is running - If the level is below 2 inches, add some to the fill tube and re-check, inspect the system for leaks - If the Heat Transfer Fluid level is OK, re-install the brass cap tightly and place the dipstick in it’s original position. |
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Inspect the Mixing Valve
After the next sunny day, open a hot water tap, sink, shower, or faucet. With the tap still open and the water running, check the temperature of the water leaving the solar tank (left or lower temp gauge), and the water leaving the mixing valve (right or upper temp gauge). If the temp gauge on the left (or lower) is above 120 degrees, then the temp gauge on the right (or upper)should be around 120 degrees. If the temp gauge on the left (or lower) is lower than 120, then both temperature gauges should read within 5 degrees of each other.
Adjust your mixing valve
(only if temperatures are unsatisfactory)
There must be hot water (above 120 degrees) in the solar storage tank and water must be flowing in order for you to accurately adjust the valve.
- Open a hot water tap
- Remove the allen screw on the left side of the red knob located on the solar manifold.
- Once the screw is removed you can now back the knob off a bit to disengage the safety lock.
- To increase temperature turn the red knob counter clockwise, to decrease the temperature turn it clockwise. 1 full rotation will adjust the temperature 10-15 degrees.
- Observe the right (or upper) temperature gauge and adjust the knob accordingly. Gauges react slowly so you may need to wait 30 seconds.
- Once the desired temperature is set, push the red knob back in to engage the safety lock and re-install the Allen screw or just release the gray knob.
PLEASE BE CAREFUL BECAUSE THE SOLAR HEATED WATER CAN GET UP TO 180 DEGREES! We do not recommend sending temperatures exceeding 120 degrees to your existing heater.









