Bard WPV48D, Руководство по установке

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Manual 2100-250
Page 16
There are four main water quality problems associated with ground water. These are:
1. Biological Growth. This is the growth of microscopic organisms in the water and will show up as a slimy
deposit through out the water system. Shock treatment of the well is usually required and this is best
left up to the well driller. The treatment consists of injecting chlorine into the well casing and flushing
the system until all growth is removed.
2. Suspended Particles in the Water. Filtering will usually remove most suspended particles (fine sand,
small gravel) from the water. The problem with suspended particles in the water is that it will erode
metal parts, pumps, heat transfer coils, etc. So long as the filter is cleaned and periodically
maintained, suspended particles should pose no serious problem. Consult with your well driller.
3. Corrosion of Metal. Corrosion of metal parts results from either highly corrosive water (acid water,
generally not the case with ground water) or galvanic reaction between dissimilar metals in the
presence of water. By using plastic plumbing or dielectric unions galvanic reaction is eliminated. The
use of corrosion resistant materials (such as the Cupro Nickel coil) through the water system will reduce
corrosion problems significantly.
4. Scale Formation. Of all the water problems, the formation of scale by ground water is by far the most
common. Usually this scale is due to the formation of calcium carbonate by magnesium carbonate or
calcium sulfate may also be present. Carbon dioxide gas (CO2), the carbonate of calcium and
magnesium carbonate, is very soluble in water. It will remain dissolved in the water until some outside
factor upsets the balance. This outside influence may be a large change in water temperature or
pressure. When this happens, enough carbon dioxide gas combines with dissolved calcium or
magnesium in the water and falls out of solution until a new balance is reached. The change in
temperature that this heat pump produces is usually not high enough to cause the dissolved gas to fall
out of solution. Likewise, if pressure drops are kept to a reasonable level, no precipitation of carbon
dioxide should occur.
REMEDIES OF WATER PROBLEMS
Water Treatment. Water treatment can usually be economically justified for closed loop systems. However,
because of the large amounts of water involved with a ground water heat pump, water treatment is generally
too expensive.
Acid Cleaning the Water Coil or Heat Pump Recovery Unit. If scaling of the coil is strongly suspected, the coil
can be cleaned up with a solution of Phosphoric Acid (food grade acid). Follow the manufacturer's directions
for mixing, use, etc. Refer to the "Cleaning Water Coil," Figure 15. The acid solution can be introduced into
the heat pump coil through the hose bib (part 8 of Figure 15). Be sure the isolation valves (parts 9 and 11 of
Figure 15) are closed to prevent contamination of the rest of the system by the coil. The acid should be
pumped from a bucket into the hose bib (part 8 of Figure 15) and returned to the bucket through the other
hose bib (part 10 of Figure 15). Follow the manufacturer's directions for the product used as to how long the
solution is to be circulated, but it is usually circulated for a period of several hours.
FIGURE 15
CLEANING WATER COIL
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