FILLING AND WATER TREATMENT : GLYCOL IN STEEL WATER TANKS
GLYCOL IN STEEL WATER TANKS On occasion, customers ask about using glycol in the GARN tank directly. There are several reasons one may want to do this, but the primary reason is to eliminate freeze potential if the unit will be unattended for long periods of time. But glycol reduces thermal storage capacity, decreases heat transfer, requires larger pumps, can cause leaking around standard valve seals, is not compatible with the water treatment chemicals, and degrades over time with the potential of increased corrosion. Because of these reasons, glycol is NOT recommended for use in any GARN WHS unit. If there is a concern about freezing provide additional thermal insulation and install the GARN 16.5 kW electric backup kit.
precipitated out of the water (the sludge and debris). The remaining water can then be considered clean, properly treated water that will keep the GARN unit healthy. Ideally, the water in a GARN unit is relatively clear. The bottom of the tank and heat exchanger tubing should be visible from the manway access. If a brown/tan/milking sludge or debris is present on the bottom of the tank such that the bottom steel is not visible, then follow the instructions on this sheet. Cleaning is most easily accomplished outside of the heating season. If the tank bottom or heat exchanger tubing is not visible, then the water is not relatively clear. In such a case, a bypass filter should be installed on the unit in addition to cleaning.
HOW TO CLEAN A GARN UNIT (SAVING THE TREATED WATER) This section discusses methods that can be used to clean a GARN unit. These methods are: 1. Holding Tank and Re-fill method 2. Vacuum, separation, and filtration method (like getting dirt off the bottom of a pool or cleaning a fish tank) 3. Drain, clean, and refill method. Why and When do I need to clean my GARN unit? The most critical factor for ensuring a long and healthy life of a GARN unit is the quality of its water. Initial and ongoing water testing and treatment is used to protect every GARN unit with properly conditioned water. The issue is that water is very hard to control for every imaginable water condition. Water varies so greatly from area-to- area that it is exceedingly difficult to test for every element, impurity, chemical, and substance that could be present in the water of a GARN unit. Water quality can even vary drastically between neighbors in the same town only a couple of miles apart. The greatest corrosion risk occurs from under deposit corrosion . Such corrosion is a result from sludge and debris sitting on the bottom of the tank for extended periods of time. The sludge and debris prevents the chemical from reaching the surface of the steel. Without treatment, the steel begins to corrode which can result in a tank eventually leaking. For some customers, sludge and debris form because of the condition of the water. Removing the sludge and debris should remedy the condition because it will remove the impurities that
Holding Tank and Re-Filling Method :
The idea here is to remove all of the good, chemically-treated water from the GARN unit and move it to a holding tank. As the water is removed, leave the sludge, flock, and debris behind. Then flush the debris and sludge out of the GARN and clean the GARN tank with water from the fill water source. After cleaning the GARN tank, refill with the chemically treated water from the holding tank. Top off the water as needed from the same fill water source. To accomplish this:
GARN WHS 1000 and WHS 2000 Manual © HY-C Company LLC - September 2024
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