Bard QW2S1 Installation Instructions Manual

Bard QW2S1 Installation Instructions Manual Manual pdf 36 page image

Manual 2100-532BPage 36 of 46MIS-2750Hose Bib (A)Hose Bib (B)PumpIsolation ValveTO WATER COILFROM WATER COILLAKE AND POND INSTALLATIONSLakes and ponds can provide a low cost source of waterfor heating and cooling with a ground water heat pump.Direct usage of the water without some filtration is notrecommended as algae and turbid water can foul thewater to freon heat exchanger. Instead, there have beenvery good results using a dry well dug next to the waterline or edge. Normal procedure in installing a dry wellis to backhoe a 15 to 20 foot hole adjacent to the body ofwater (set backhoe as close to the water’s edge aspossible). Once excavated, a perforated plastic casingshould be installed with gravel backfill placed aroundthe casing. The gravel bed should provide adequatefiltration of the water to allow good performance of theground water heat pump.The following is a list of recommendations to followwhen installing this type of system (Refer to Figure 25):A. A lake or pond should be at least 1 acre (40,000 asquare feet) in surface area for each 50,000 BTUs ofground water heat pump capacity or have 2 times thecubic feet size of the dwelling that you are trying toheat (includes basement if heated).B. The average water depth should be a least 4 feet andthere should be an area where the water depth is atleast 12 to 15 feet deep.C. If possible, use a submersible pump suspended in thedry well casing. Jet pumps and other types ofsuction pumps normally consume more electricalenergy than similarly sized submersible pumps.Pipe the unit the same as a water well system.D. Size the pump to provide necessary GPM for theground water heat pump. A 12 GPM or greaterwater flow rate is required on all modes when usedon this type system.E. A pressure tank should be installed in dwelling to beheated adjacent to the ground water heat pump. Apressure switch should be installed at the tank forpump control.F. All plumbing should be carefully sized tocompensate for friction losses, etc., particularly ifthe pond or lake is over 200 feet from the dwellingto be heated or cooled.G. Keep all water lines below low water level andbelow the frost line.H. Most installers use 4-inch filed tile (rigid plastic orcorrugated) for water return to the lake or pond.I. The drain line discharge should be located at least100 feet from the dry well location.J. The drain line should be installed with a slope of 2inches per 10 feet of run to provide completedrainage of the line when the ground water heatpump is not operating. This gradient should alsohelp prevent freezing of the discharge where thepipe terminates above the frost line.K. Locate the discharge high enough above high waterlevel so the water will not back up and freeze insidethe drain pipe.L. Where the local conditions prevent the use of agravity drainage system to a lake or pond, you caninstead run standard plastic piping out into the pondbelow the frost and low water level.FIGURE 24CLEANING WATER COIL