User Guide
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Plate Type Heat Exchangers, Single plate & Semi-welded - Installation, Commissioning and Maintenance
18 | BC172686461130en-000201
© Danfoss | DCS (ms) | 2019.07
Most common problems with a plate heat
exchanger, can be solved by own trained
personnel. Fig.16 lists a summary of possible
problems together with relevant possible causes
and solutions.
To maintain a continuous proper function of the
plate heat exchanger ,it is essential to keep the
operating pressure and temperature within the
ranges stated on the nameplate.
For nearly all leakage problems it will be
necessary to dismantle the unit before any
attempts to rectify the fault can be made. Mark
the area(s) where the leakage seems located
with a felt tip marker or similar before
disassembling the plate heat exchanger. Follow
the instructions in section "Opening the plate
heat exchanger".
“Cold leakage” is caused by a sudden change in
temperature. The sealing properties of certain
elastomers are temporarily reduced when the
temperature changes suddenly. No action is
required as the gaskets most often re-seal after
the temperature has stabilized.
Exceeding these values, even as short-lasting
peaks, may damage the unit or could be the
cause of problems/issues.
To avoid costly repairs, it is recommended to
have the installation and maintenance carried
out by properly trained personnel.
Troubleshooting
Problem
Possible cause
Possible solution
Leakage
Connection sealing damaged
Check the rubber liners (if fitted)
Check the flange gasket (if fitted)
Check the ring gasket at first plate
Fit the pipes tension-free
Mixing of primary and secondary circuit
Check the plates for holes and/or cracks
Single plate:
Check the gaskets around the
port and diagonal areas
Semi-welded: Check the diagonal part of the
field gasket and ring gasket
Plate package sealing damaged
Check the assembly distance "A"
Check the condition of the gaskets
Check the proper position of the gaskets
The operating conditions deviate from the
specification
Adjust the operating conditions
Insufficient capacity
Air in the system
Vent the piping system
Check the pipe work for possible air traps
The operating conditions deviate from the
specification
Adjust the operating conditions
The heat exchanger is fouled internally
Clean the heat exchanger
The connections have been interchanged
Redo the pipe work
Too high
pressure drop
Flow larger than the design flow
Adjust the flow
Channels in plates blocked
Flush / clean
Incorrect measurement
Check the pressure indicator
Fluid deviating from the specification
Check the chemical composition
Air in the system
Vent the piping system
Check the pipe work for possible air traps
Fig. 16. Summary of possible problems, causes and solutions
