System Cleaning And Flushing - McQuay 5WSS Serie Manual De Instrucciones

Water Pressure Drop Table
Model Water Flow Rate
3
m /hr
0.2
5WSS07AR 0.4
0.6
0.3
5WSS10AR 0.5
0.7
0.5
5WSS15AR 0.7
0.9
0.7
5WSS16AR 0.9
1.1
1.0
5WSS20AR 1.2
1.4
The water circulating loop system must be cleaned and flushed to remove all construction debris and dirts before operating the units.
1. If the connection is equipped with water shut-off valve, either electric or pressure operated, the individual supply and
return pipes must be connected together first. This will prevent the introduction of dirt into the unit.
2. Fill the water loop system with your local water supply with all air vents open. After filling, close all air vents. The
contractor should start the main circulator pump with the pressure reducing valve open. Check all vents in sequence to
bleed off any trapped air, ensuring circulation through all components of the system. Power to the heat rejector unit should
be off and the supplementary heat control set at 27
3. While the water is circulating, the contractor should check and repair any leaks in the piping. Drains at the lowest point(s)
in the system should be opened for initial flush and blow down. Make sure the local supply water valves are set to make up
for the required flow rate. Check the pressure gauge at the pump suction and manually adjust the make up to hold the same
positive steady pressure both before and after opening the drain valves. Flush should be continuously for two hours or
longer if required to obtain a clean and clear drain water.
4. Shut off all supplemental heater and circulator pump and open all drains and vents to complete drain down the system.
Now, the short-circuited water connection to the supply and return pipes should be removed and connected to the indi-
vidual water inlet and outlet of the unit. Use proper tape to seal off at the valve connection. Do not use sealant at the valves
connection.
5. Trisodium phosphate was formerly recommended as a cleaning agent during flushing. However, some of the local authori-
ties ban the usage of the phosphate into the sewage systems. The current recommendation is to simply flush longer with
warm at 27 o C (80 o F) water.
6. Refill the water loop system with clean water. Test the water for acidity by using a litmus paper. Treat the water if required
to obtain the pH level between 7.5 to 8.5 (slightly alkaline). If antifreeze is required, use only antifreeze designed for
HVAC. Do not use automotive grade antifreeze.
7. Once the water system is ready, ensure at all times only clean water is supply to the system. Dirty water will result in wide
degradation of performance and solids may clog valves, strainers, flow regulator, etc. Pump work will increase and may
damage the pumps. The heat exchanger may become clogged as well which will reduce the compressor service life or
causes premature failure.
8. Finally set the loop water controller heat addition point to 21
Supply power to all motors and start the circulating pumps. After full flow has been established through all components
including heat rejector (regardless of season) and air vented and loop temperature stabilized, each of the air conditioners
will be ready for check, test and start up, air balancing and water balancing.
Pressure Drop
kPa
3.71
5.00
6.65
4.28
5.80
7.63
5.80
7.63
9.72
2.93
4.58
7.46
13.06
15.35
19.03

SYSTEM CLEANING AND FLUSHING

o o
C (80 F).
1-7
Model Water Flow Rate
3
m /hr
1.2
5WSS25AR 1.4
1.6
1.6
5WSS30AR 1.8
2
1.9
5WSS40AR 2.1
2.3
2.3
5WSS50AR 2.5
2.7
3
5WSS60AR 3.2
3.4
o C (70 o F) and the heat rejection set point to 29
Pressure Drop
kPa
14.86
19.46
23.72
24.76
30.59
36.42
7.53
9.49
12.03
6.67
8.98
11.83
16.31
19.28
22.21
o C (85 o F).