Heat Controller HTV, HTH, HTD manual Preventive Maintenance

Page 42

Installation, Operation & Maintenance

HTV/HTD/HTH SERIES

Heat Controller, Inc.

Preventive Maintenance

Water Coil Maintenance

(Direct ground water applications only) - If the system is installed in an area with a known high mineral content (125 P.P.M. or greater) in the water, it is best to establish a periodic maintenance schedule with the owner so the coil can be checked regularly. Consult the well water applications section of this manual for a more detailed water coil material selection. Should periodic coil cleaning be necessary, use standard coil cleaning procedures, which are compatible with the heat exchanger material and copper water lines. Generally, the more water flowing through the unit, the less chance for scaling. Therefore, 1.5 gpm per ton [2.0 l/m per kW] is recommended as a minimum flow. Minimum flow rate for entering water temperatures below 50°F [10°C] is 2.0 gpm per ton [2.6 l/m per kW].

Water Coil Maintenance

(All other water loop applications)

Generally water coil maintenance is not needed for closed loop systems. However, if the piping is known to have high dirt or debris content, it is best to establish a periodic maintenance schedule with the owner so the water coil can be checked regularly. Dirty installations are typically the result of deterioration of iron or galvanized piping or components in the system.

Open cooling towers requiring heavy chemical treatment and mineral buildup through water use can also contribute to higher maintenance. Should periodic coil cleaning be necessary, use standard coil cleaning procedures, which are compatible with both the heat exchanger material and copper water lines. Generally, the more water flowing through the unit, the less chance for scaling. However, flow rates over 3 gpm per ton (3.9 l/m per kW) can produce water (or debris) velocities that can erode the heat exchanger wall and ultimately produce leaks.

Hot Water Generator Coils

See water coil maintenance for ground water units. If the potable water is hard or not chemically softened, the high temperatures of the desuperheater will tend to scale even quicker than the water coil and may need more frequent inspections. In areas with extremely hard water, a HWG is not recommended.

Filters

Filters must be clean to obtain maximum performance. Filters should be inspected every month under normal operating conditions and be replaced when necessary. Units should never be operated without a filter.

Washable, high efficiency, electrostatic filters, when dirty, can exhibit a very high pressure drop for the fan motor and reduce air flow, resulting in poor performance. It is especially important to provide consistent washing of these filters (in the opposite direction of the normal air flow) once per month using a high pressure wash similar to those found at self-serve car washes.

Condensate Drain

In areas where airborne bacteria may produce a “slimy” substance in the drain pan, it may be necessary to treat the drain pan chemically with an algaecide approximately every three

months to minimize the problem. The condensate pan may also need to be cleaned periodically to insure indoor air quality. The condensate drain can pick up lint and dirt, especially with dirty filters. Inspect the drain twice a year to avoid the possibility of plugging and eventual overflow.

Compressor

Conduct annual amperage checks to insure that amp draw is no more than 10% greater than indicated on the serial plate data.

Fan Motors

All units have lubricated fan motors. Fan motors should never be lubricated unless obvious, dry operation is suspected. Periodic maintenance oiling is not recommended, as it will result in dirt accumulating in the excess oil and cause eventual motor failure. Conduct annual dry operation check and amperage check to insure amp draw is no more than 10% greater than indicated on serial plate data.

Air Coil

The air coil must be cleaned to obtain maximum performance. Check once a year under normal operating conditions and, if dirty, brush or vacuum clean. Care must be taken not to damage the aluminum fins while cleaning. CAUTION: Fin edges are sharp.

Cabinet

Do not allow water to stay in contact with the cabinet for long periods of time to prevent corrosion of the cabinet sheet metal. Generally, vertical cabinets are set up from the floor a few inches [7 - 8 cm] to prevent water from entering the cabinet. The cabinet can be cleaned using a mild detergent.

Refrigerant System

To maintain sealed circuit integrity, do not install service gauges unless unit operation appears abnormal. Reference the operating charts for pressures and temperatures. Verify that air and water flow rates are at proper levels before servicing the refrigerant circuit.

42

Image 42
Contents HTV/HTD/HTH Series Two-Stage Geothermal Heat Pumps To 6 Tons Table of Contents Safety General Information Horizontal Unit Location Hanger BracketHorizontal Installation Typical Horizontal Unit InstallationField Conversion of Air Discharge Side to Back Discharge ConversionDuct System Installation Condensate Piping Horizontal Unitsರ3HU RRW Vertical Installation Vertical Unit LocationReturn Using a threaded pipe or similar device to clearMay ease final drain line installation Air InletExternal Flow Controller Mounting Water Connection InstallationPiping Installation Flushing the Earth LoopFluid Volume gal liters per 100’ 30 meters Pipe Ground-Loop Heat Pump ApplicationsAntifreeze Water Quality Standards Antifreeze Percentages by VolumeOpen Loop Ground Water Systems Pressure Tank and PumpGround-Water Heat Pump Applications Typical Open Loop/Well ApplicationWater Quality Standards Typical HWG Installation Hot Water GeneratorControl Logic Error InstallationHigh Water Temperature 160ºF ÅashesHWG Water Piping Water Tank PreparationInitial Start-Up Water Tank RefillElectrical Line Voltage HT Series Electrical DataHWG Wiring Split Units Only General Line Voltage WiringPower Connection Electrical Line VoltageLow Water Temperature Cutout Selection Electrical Low Voltage WiringLow voltage Äeld wiring for units with ECM fan Thermostat ConnectionsAccessory Connections Two-stage UnitsFault LED Electrical Thermostat WiringThermostat Installation ATM21U01ECM Blower Control ECM Board Tap Settings HT UnitsHT Series ECM Blower Performance Data CXM Controls Safety Features CXM Control Diagnostic FeaturesUnit Operation Stat signal CXM Control Start-up OperationECM fan PSC fan CXM Thermostat Details Nominal resistance at various temperaturesThermostat Signals Not compatible with the CXMCommissioning Conditions Unit Commissioning And Operating ConditionsOperating Limits Voltage utilization range complies with Ahri StandardUnit Start-Up and Operating Conditions Before Powering SYSTEM, please check the followingUnit Start-up Procedure Unit and System CheckoutUnit Start-Up Procedure HT Coax Water Pressure Drop Water Temperature Change Through Heat ExchangerUnit Operating Conditions Antifreeze Correction TableHT Series Typical Unit Operating Pressures and Temperatures PsigGPM Performance Data HT 024 Full Load Cooling EAT 80/67FPerformance Data HT 036 Full Load Performance Data HT 048 Full Load Performance Data HT 060 Full Load Performance Data HT 070 Full Load Preventive Maintenance Troubleshooting CXM Functional Troubleshooting Flow Chart CXM Process Flow ChartFunctional Troubleshooting Main power problemsPerformance Troubleshooting Performance Troubleshooting Htg Clg Possible Cause SolutionTroubleshooting Form +&$97B00