Compressor Maintenance; Electrical Controls - York YVWA Installation Operation & Maintenance

SECTION 7 - MAINTENANCE
Mechanical Tube Cleaning Procedure
1. Drain the water from the condenser.
2. Remove the water boxes from both ends of the
condenser with proper lifting equipment. Use cau-
tion not to damage the threads on the mounting
studs that are welded to the tube sheet.
3. Select a tube cleaning brush for 5/8 in. ID copper
condenser tubes. If tubes other than those with 5/8
in. ID 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. DO NOT use a steel
bristle brush.
4. Attach the tube cleaning brush to the end of a
cleaning machine or 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 box onto the condenser.

COMPRESSOR MAINTENANCE

Perform maintenance on the compressor assembly
by:
1. Checking the operation of the oil return system
and changing the dehydrator.
2. Checking and changing the oil, and oil filters.
3. Checking the operation of the oil heater.
4. Observing the operation of the compressor.
Internal wearing of compressor parts could be a seri-
ous problem caused by improper lubrication, brought
about by restricted oil lines, passages, or dirty oil fil-
ters. If the unit is shutting down on low oil pressure
(LOP), change the oil filter element and examine it for
foreign material. If foreign material is noticeable and
the same conditions continue to stop the unit operation
after a new filter element is installed, contact a John-
son Controls Field Service Office.
144

ELECTRICAL CONTROLS

For information covering the control center operation,
refer to SECTION 6 - OPERATION in this manual,
and Field Connections and Control Wiring for YVWA
Chiller (Form 201.30-PW2).
Checking VSD Coolant Level
Never run the coolant pump without cool-
ant! Running the coolant pump without
coolant may damage the pump seals.
Always fill the system with approved
YORK coolant to avoid damage to the
pump seals and the chiller.
The chiller is shipped with a 50/50 mix of Propylene
Glycol and York Corrosion Inhibitors. This type of
coolant is being used to protect the cooling loop from
damage due to freezing conditions during the shipping
process. This coolant mixture does not have the ther-
modynamic properties required by the variable speed
drive, and must be removed. Drain the coolant from
the variable speed drive.
This 50/50 mixture must be drained and replaced with
YORK Corrosion Inhibitor as specified below.
1. Drain the coolant from the variable speed drive.
2. Fill the coolant loop using York's Corrosion In-
hibitor, part number 013-04129-000. Pour the
solution into the top of the header pipe until the
level is within a ½ inch of the top.
3. Then manually run the pump to remove pockets
of air. Observe the level in the fill-pipe, and more
coolant as necessary to bring the level back to ap-
prox.. ½ from the top of the pipe.
4. Continue to run the pump manually for 15 min-
utes, adding more coolant as needed. Then rein-
stall the pipe plug in the header pipe using teflon
tape to assure coolant does not evaporate through
the pipe threads. Do not wrap the threads with
more than 2 wraps of Teflon tape. Too much tape
can cause the fill pipe to crack.
FORM 201.30-ICOM1 (519)
ISSUE DATE: 05/22/2019
JOHNSON CONTROLS