York YGWH 115, Installation, Commissioning & Operation

7-3

EN

Form 6S6I-B01C-EOMA-EN (0318)

Reliable water treatment companies are available in  

most large cities to supply a water treating process 

which will greatly reduce the corrosive and scale 

forming properties of almost any type of water. 

As a preventive measure against scale and corrosion 

and prolong the life of evaporator and condenser tubes, 

a chemical analysis of water should be made, preferably 

before the system is installed. A reliable water treatment 

company can be consulted to determine whether water 

treatment is necessary, and if so, to finish the proper 

treatment for particular water condition.

Condenser and evaporator water side tube cleaning 

procedure

The standard condenser tubes used in YORK YGWH 

Chiller are internally enhanced copper tubes.

If the equipment is located in an unheated 

area that is susceptible to freezing, the 

water must be drained from the condenser 

to prevent tube failure from freezing.

Proper condenser water treatment can 

eliminate or significantly reduce the formation of scale 

on the waterside of the condenser tubes.

Maintain a minimum condenser water flow rate through 

the tubes of at least 3.33 ft/sec. (1 meter/sec.). Through 

tube water velocity should not exceed 12 ft/sec. (3.6 

meter/sec.).

Condenser tubes must be maintained to provide proper 

chiller operation. Condenser Approach Temperature is a 

useful tool to monitor the performance of the condenser. 

By recording and logging the Condenser Approach 

Temperature as part of the chiller maintenance 

program, this will provide a warning that the waterside 

condenser tubes are fouled and require cleaning. 

Condenser  Approach  Temperature  is  the  difference 

between the Condenser Leaving Water Temperature 

and the Saturated Condensing Temperature.

If  the  approach  increases  above  3.5°C,  or  during 

the annual condenser inspection and the tubes are 

observed to be fouled, the tubes will require cleaning. 

For  condenser  fluids  other  than  water  consult  with 

the  local  YORK  Field  Service  Office  for  the  correct 

condenser approach temperature.

Condenser water side tube cleaning procedure

Two methods are used for waterside tube cleaning to 

remove the scale; chemical and mechanical cleaning 

procedures. The composition of the scale will determine 

which method will be most effective to remove the scale 

and dirt.

Consult  with  the  local YORK  Field  Service  Office  for 

a recommendation of the method(s) used in the local 

area.

Chemical Cleaning Procedure

Chemical  cleaning  is  an  effective  method  to  remove 

scale from internally enhanced copper tubes. However, 

a company knowledgeable with the chemical cleaning 

procedure should be contracted or consulted. Follow 

the chemical cleaning company recommendations 

concerning solution cleaning strength and time duration 

of the cleaning process.

Serious damage to the condenser tubes will result if 

the chemical cleaning procedure is improperly applied.

Mechanical tube cleaning must always follow a 

chemical cleaning procedure.

When chemical cleaning of the condenser tubes 

is required,  it may be necessary to calculate the 

internal volume of the waterside condenser tubes. This 

information  is  necessary  to  properly  mix  the  correct 

concentration of cleaning solution.

Standard materials of construction for YORK YGWH 

Chiller condensers is copper tubes and mild carbon 

steel water boxes.

Mechanical Cleaning Procedure

1. Drain the water from the condenser.

2.  Remove  the  water  boxes  from  both  ends  of  the 

condenser. Use proper lifting equipment when 

removing the water boxes. Use caution not to damage 

the threads on the mounting studs that are welded to 

the tube sheet.

3. Select a tube cleaning brush for 3/4 inch 

I.D copper condenser tubes. If tubes other 

than 3/4 inch copper are used, select a tube 

cleaning brush that is made for the tube size. 

Generally, brushes made of hard plastic or brass 

bristled wires are preferred for cleaning copper tubes.

4. Attach the tube cleaning brush to the end of a 

cleaning machine or cleaning rod.

5. Flush the condenser with clean water to remove the 

debris.

6. Replace the water box gasket with a new gasket and 

reassemble the water boxes onto the condenser.