Routine Maintenance of HVAC Recirculated Water System

The Routine Maintenance of HVAC Re-circulated Water System

Routing maintenance of HVAC re-circulated water system is recommended to keep the system any kind of trouble-free. Routine maintenance or preventive maintenance determines the continuous services as well as ensures increasing the lifetime of machinery.

Strainer Maintenance:

The pan strainer should be removed and cleaned at least once a month or as often as necessary to keep it clean.

 Pan Maintenance:

The pan should be flushed out quarterly or as often as necessary to keep down any accumulation of dirt. 

Maintain Water Make-Up:

The float switch and valve should be checked at least once a month to make sure that the recommended water level is correct.  The correct water level must vary according to the model number. The recommended water level should be found in the manufacturer-provided catalog.

Initial starting time or after draining down the unit, the water system must be filled to overflow.  Overflow is above the normal operating level and accommodates the volume of water normally in suspension and in the water distribution system.  

The water level should always be above the strainer and pump suction.  Check by running the pump with the fans off and observing the water level through the access door.  Maintain make-up water pressure within the manufacturer's prescribed value.

Pressurized Water Distribution Systems Maintenance:

Check the water distribution system every month to ensure it is operating properly. Check the spray system with the pump on and the fans off.  The diffuses are essentially non-clogging and should rarely need cleaning or maintenance.

If dirt or any foreign matter accumulates in the water system or pan and the system strainer is not working properly then the water diffuser may malfunction. The nozzles can be cleared by using a small pointed probe and moving it rapidly back and forth in the diffuser opening with the pumps running and the cooling load and fans off.  

If dirt or foreign matter occurs, remove the end cap in each branch to flush the debris from the header pipe.  The branches or header can be removed for cleaning. Check the strainer condition and position; also check that the orientation of the water diffusers is placed correctly.

Gravity Feed Water Distribution Systems Maintenance:

Cross-flow cooling towers use a gravity-feed distribution system.  Hot water is pumped into distribution pans and is drained by gravity through a matrix of diffuser heads.  The hot-water distribution pans and diffusers are accessed from the top of the unit by sliding back the FRP pan cover.  The top of the anti-vortex type diffuser can be pulled off if necessary, allowing debris to be removed.  The lower body of the diffuser can be removed by turning and pulling. 

Bleed-Off Valve Maintenance:

The bleed-off valve may factory factory-fitted or installed at the site, that does not matter, must be checked once a week. If not working properly, be sure it may cause scaling or corrosion.

Pump and Pump Motor Maintenance: 

The pump and pump motor should be checked regularly, if necessary lubricated, and serviced in accordance with the pump manufacturer’s instructions as supplied with the unit.

Following the “routine maintenance of re-circulated water system” as per manufacturer’s instruction, optimized performance and maximum efficiency might be possible to get from the re-circulated water system equipment.