The project specifications are the guidelines for test data and measurement procedures on all projects. All test and balance procedures are detailed in the “NEBB Procedural Standards for Testing, Adjusting and Balancing of Environmental Systems, Seventh Edition 2005”. The following was selected from that manual and applies to most projects.
PREPARATION PROCEDURE FOR WATER BALANCE
1. Air balance should be completed before water balance begins.
2. Open all valves to full open position. Close coil bypass stop valves. Set mixing valve to full coil flow.
3. Verify that the responsible parties have removed and cleaned all strainers.
4. Examine water in system and determine if water has been treated and cleaned.
5. Check pump rotation.
6. Check expansion tanks to determine they are not air bound and the system is completely full of water.
7. Check all vents at high points of water systems and determine all are operating freely.
8. Set all temperature controls so all coils are calling for full cooling. This should close all automatic bypass valves at coil and chiller. Same procedure when balancing hot water coils; set on call for full heating.
9. Check operation of automatic bypass valve.
10. Check and set temperatures of boilers and chillers to design requirements.
TEST AND BALANCE PROCEDURE:
1. Set chilled water and hot water pumps to proper flow (GPM).
2. Adjust chilled water flow through chiller.
3. Adjust water flow through boilers.
4. Check leaving water temperatures and return water temperatures through chiller and boilers. Reset to correct design temperatures.
5. Check water temperatures at inlet side of cooling and heating coils. Note rise or drop of temperatures from source.
6. Proceed to balance each chilled water cold and hot water coil.
7. Upon completion of low readings and adjustments at coils, mark settings and record data.
8. After adjustments to coils are made, recheck settings at the pumps, chillers and boilers and readjust, if required.
9. With full flow through the bypass, set the pressure drop across the bypass valve to match coil flow pressure drop. This prevents unbalanced flow conditions when coils are on bypass.
10. Same procedure on chiller to adjust chiller bypass valve.
11. Record and check the following items at each cooling and heating elements.
12. Pressure drop of each coil
13. Pressure drop across bypass valve.
14. Pump operating suction and discharge pressures and final T.D.H.
15. List all mechanical specifications of pumps.
16. Rated and actual running amperage of pump motor.
17. Water metering device readings
1. Verify that all control settings have been returned to normal set points.
2. Verify that all discrepancies and punch list items have been corrected.
3. Allow the system to operate automatically for 24 hours.
4. Identify all rooms on temperature test sheets.
5. Note room numbers where all thermostats are located. Record set points of all thermostats.
6. Record temperatures in all rooms. Record outside air temperatures and weather conditions at the beginning and end of temperature tests.
7. Recheck operation of all HVAC equipment in any room that is not maintaining temperature set point and correct, if necessary.
HVAC TEST and BALANCE SERVICE