Airwell HRW 07, Руководство по установке и обслуживанию

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15
RECOMMENDATIONS FOR CLEANING AND FLUSHING OUT THE SYSTEM
1. Before commissioning an appliance for the first time, the water loop must be cleaned and rinsed out
to remove any dirt and manufacturing debris.
If the appliances are equipped with isolation valves
(either electric or pressostatic), the water supply and
return conveyance circuits to and from each machine
must be connected to each other. This will avoid any
dirt being introduced into the units.
Flushing water through the units is acceptable if they
are not equipped with water flow control devices.
2. The system must be filled from the mains water
supply. All air bleeds must be open during filling.
Close the air bleeds once the system is filled.
The installer must start the main circulation pump
with the water top-up tap on the pressure reduction
valve in the open position. Check the air bleeds by
increasing order of height to ensure water flows freely
throughout the entire system.
Power supply to the cooling tower must be shut
down, and the water loop temperature regulation
thermostat must be set at 27 °C.
As the water circulates through the system, the installer must seek out and repair any possible pipe
work leaks. The drain cocks, on the lowest points on the circuit, must be open for flushing out and
chasing out any impurities. Ensure that the mains water valves are adjusted to allow water to enter at
the same speed as it exits. Check the pump inlet pressure gauge and manually adjust the compensating
valve to maintain the same pressure before and after the opening of the drain taps. Flushing must
be performed for at least two hours, or longer if necessary, until clear and clean water is obtained at
the drain taps.
3. Stop the additional heating and the water circulation pump. Open all the bleed points and the drain
taps to empty the system completely. The short-circuited water supplies and returns must now be
connected to the units’ inlet and outlet connections. It is recommended to use Teflon tape on the
pipe connector threads. Do not use sealing paste on the hoses’ rotating connecters.
4. Formerly, sodium tri-phosphate used to be recommended as a cleaning agent for flushing.
However, nowadays numerous countries forbid the introduction of phosphates into their wastewater
networks.
Therefore, it is now recommended that the system is flushed out with hot water
(30 °C).
5. Fill the system again with clean water. Test the water acidity level (litmus paper), and treat as required
to obtain a slightly alkaline water quality (pH 7.5 to 8.5).
At this stage, the recommended percentage of anti-freeze can be added. Use commercial quality
anti-freeze specifically intended for air conditioning systems. Do not use automobile radiator anti-
freeze.
6. On the main electrical cabinet, adjust the heater set temperature point at 20 °C and the cooling tower
set temperature at 30 °C. Connect the power supply to all motors and start the circulation pumps.
When the normal flow level has been reached through all components, including the cooler (irrespective
of the season) and when the air is bled form the system and the loop temperature has stabilised, each
appliance is ready to be checked, tested and started for balancing the air and water flows.
Rubber
hose
Return conveyance
Supply conveyance
Main circuits
INTERCONNECTED
CONVEYANCES