| ENVISION CONSOLE INSTALLATION MANUAL |
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System Cleaning and Flushing |
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Cleaning and Flushing | Figure 7: Flushing with Water |
Prior to start up of any heat pump, the water circulating system must be | Shutoff Valve Equipped Systems |
cleaned and flushed of all dirt and debris. |
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If the system is equipped with water shutoff valves, the supply and return runouts must be connected together at each unit location (This will prevent the introduction of dirt into the unit, see Figure 7). The system should be filled at the water
The contractor should start the main circulator with the pressure reduc- ing valve makeup open. Vents should be checked in sequence to bleed off any trapped air and to verify circulation through all components of the system.
Return Runout
Supply Runout
Mains
Rubber Hose
Runouts Initially
Connected Together
As water circulates through the system, the contractor should check and repair any leaks found in the piping system. Drain(s) at the lowest
point(s) in the system should be opened for initial flush and blowdown, making sure water fill valves are set at the same rate. Check the pressure gauge at the pump suction and manually adjust the
The supplemental heater and/or circulator pump, if used, should be shut off. All drains and vents should be opened to completely drain the system.
Refill the system with clean water. Test the system water for acidity and treat as required to leave the water slightly alkaline (pH 7.5 to 8.5). The specified percentage of antifreeze may also be added at this time. Use commercial grade antifreeze designed for HVAC systems only. Environol™ brand antifreeze is recommended..
Once the system has been filled with clean water and antifreeze (if used), precautions should be taken to protect the sys- tem from dirty water conditions. Dirty water will result in
In boiler/tower application, set the loop control panel set points to desired temperatures. Supply power to all motors and start the circulating pumps. After full flow has been established through all components including the heat rejector (re- gardless of season), air vented and loop temperatures stabilized, each of the units will be ready for check, test and start up and for air and water balancing.
Ground Source Loop System Checkout
Once piping is completed between the unit pumping system and ground loop, final purging and charging of the loop is needed. A high pressure pump is needed to achieve adequate flow velocity in the loop to purge air and dirt particles from the loop itself. Antifreeze solution is used in most areas to prevent freezing. Flush the system adequately to remove as much air as possible; then pressurize the loop to a static pressure of
Insure the pump provides adequate flow through the unit by checking pressure drop across the heat exchanger. Usually
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