General .......................................................................................................................................................................................................................... 4
Design: Single plate and Semi-welded .............................................................................................................................................. 6
Single Plates .................................................................................................................................................................................................... 6
Right (R)/ Left (L) plates ........................................................................................................................................................................... 7
Right and left plates, Single plates .................................................................................................................................................. 7
Transport and lifting .................................................................................................................................................................................. 9
Piping system .........................................................................................................................................................................................................10
Installing the pipe connections.......................................................................................................................................................10
Start-up process .........................................................................................................................................................................................11
Shut-down for a short period ...........................................................................................................................................................12
Shut-down for a long period .............................................................................................................................................................12
Opening the plate heat exchanger..............................................................................................................................................13
Closing the plate heat exchanger ..................................................................................................................................................16
Regular Service of the plate heat exchanger .........................................................................................................................17
Additional service for semi-welded heat exchanger .......................................................................................................17
After sales service ...................................................................................................................................................................................... 19
Ordering parts .............................................................................................................................................................................................19
Modications to the heat exchanger ..........................................................................................................................................19
User Guide | Plate Type Heat Exchangers, Single plate & Semi-welded - Installation, Commissioning and Maintenance
Introduction
Safety alert notices
This user guide is a guide for installation,
commissioning and maintenance of plate type
heat exchangers supplied by Danfoss.
It is meant for those who are responsible for the
installation, the use and maintenance of the heat
exchangers. We recommend that you read this
user guide carefully before commencing any
work.
This user guide is applicable for all plate type
heat exchangers produced and supplied by
Danfoss.
Danfoss can not be held responsible or liable for
damage as a result of incorrect installation, use
and/or maintenance of Danfoss plate type heat
exchanger or damage caused by as not
complying with the instructions in this user guide.
Please note that our plate type heat exchangers
are specially designed and built for the maximum
design conditions (pressures, temperatures,
capacities and type of uids) provided by the
customer and stated on the nameplate.
The following must always be observed when
installing or servicing plate heat exchangers:
Sudden pressure peaks beyond the maximum
operating pressure (or pressure surges) which
can occur during start-up or stopping of the
system can severely damage the heat exchanger
and should be prevented. Danfoss can not be
held responsible for any damage as a result of
any operation deviating from the original design
conditions.
• Comply with national/local safety regulations
• Ensure that the heat exchanger is
unpressurized
• Ensure that the heat exchanger is cooled down
to a temperature below 40 °C (104 °F)
Warning symbols refer to safety alert notices.
Warning/safety notices should be observed
carefully to prevent:
Personal injury caused by:
• Wrong transport/lifting
• Burning/freezing as a result of touching
parts with extreme temperatures.
• Burning/freezing/poisoning as a result
of uncontrolled release of pressurized
media
User Guide | Plate Type Heat Exchangers, Single plate & Semi-welded - Installation, Commissioning and Maintenance
1727
F1
F4
F1
B1
B2
B4
B3
F1
F4
F1
B1
B2
B4
B3
1727
GeneralIdentification of the heat exchanger
All plate type heat exchangers supplied by
Danfoss are provided with a name plate
positioned on the front (head) of the heat
exchanger.
Single plate heat exchanger Nameplate
Month/year of production
Type designation
Serial number
Assembly (A) measure min.
Assembly (A) measure max.
Max. pressure drop
Min./max. working temp.
Inlet - outlet connections
Max. working pressure
Max. allowed test pressure
Total internal volume
Fluids per side
On this plate main technical details of the heat
exchanger are specied.
Before installation please make sure that the
intended application is compliant with the name
plate application data and use limitations.
MADE IN DENMARK
Plate heat exchanger type
S19
Serial No.
IRF76804
A-measure min.
159
A-measure max.
-
Max. dierential pressure
16
Min. working temperature
0
Inlet > outlet
Max. working pressure
Max. test pressure
Volume
Fluid
Month and year
12-2018
Marking
mm
mm
Bar
Max. working temperature
80
°C
Ref. Side
F4 - F1
1616
/
/
/
/
/
/
Brine side
F3 - F2
20,820,8
23,523,5
WaterWater
MM-Y Y
(*)
°C
Bar
Bar
Ltr.
Semi-welded plate heat exchanger Nameplate
Month/year of production
Type designation
Serial number
Assembly (A) measure nominal
Tolerance -1.5%
Max. pressure drop
Min./max. working temp.
Inlet - outlet connections
Max. working pressure
Max. allowed test pressure
Total internal volume
Fluids per side
F2
A-measure
F3
Manufactured by Danfoss A/S, 6430 Nordborg, Denmark
Plate heat exchanger type
SW19A-IG
Serial No.
76803
A-measure Nominal*
159
Max. dierential pressure
16
Min. working temperature
080
Inlet > outlet
Max. working pressure
Max. test pressure
Volume
Fluid
Do not exceed above values at any time.
Please read instruction manual before
installation, operation and maintenance.
mm
Bar
°C°C
Ref. Side
F4 - F1
16
20,8
23,5
NH₃
MADE IN DENMARK
Month and year
02-2019
Marking
Max. working temperature
/
Brine side
/
F3 - F2
/
16
/
20,8
/
23,5
/
PropGlycol
MM-Y Y
(*)
Bar
Bar
Ltr.
A-measure min.:
A-measure Nominal - 1.5%
F2
A-measure
F3
Manufactured by Danfoss A/S, 6430 Nordborg, Denmark
User Guide | Plate Type Heat Exchangers, Single plate & Semi-welded - Installation, Commissioning and Maintenance
Ro ller
Carrying bar
Head
Na m e P la t e
Tie bolt
Guiding bar
Plate /Cassette
Follo wer
Column
Anchoringbrackets
Design:
Single plate and
Semi-welded
Roller
Carrying bar
Column
Name Plate
Head
Anchoring
brackets
Fig. 3. Construction of generic Semi-welded heat exchanger.
Single Plate construction is identical except plates are not paired (welded) into cassettes.
Frame
The heat exchanger consists of a frame plate
(head), a pressure plate (follower), a carrying bar,
a guiding bar and a column. Tie bolts are used to
The ring gasket material is carefully selected to
match the combination of temperature and
chemical resistance requirements (e.g. NH₃ and
compressor oil on the welded side).
press the plate package together. The size and
number of bolts depend on the type of heat
exchanger.
Gaskets
The following gasket types are used in Danfoss
plate type heat exchangers:
Single Plates
Single plate pack consists of single plates tted
with a ow gasket on each plate to seal the plate
pack. The number of plates, size and dimension
depend on the thermal output required. The
number of plates determines the total heat
• Sonderlock gaskets
• Glued gaskets
• Sonder Snap gaskets (semi-welded plate heat
exchangers, large range)
• Hang-on gaskets (semi-welded plate heat
exchangers)
transfer area (surface).
Semi-welded plates (plate cassettes)
A plate cassette consists of two single ow plates
welded together, creating a sealed ow channel.
The cassettes are tted with two individual
gaskets, a ring gasket and a eld gasket, to seal
the plate pack preventing the intermixing of
media. This gasket design allows the use of
dierent gasket materials for the ring and eld
gaskets respectively for best t to the actual
media and temperature conditions.
User Guide | Plate Type Heat Exchangers, Single plate & Semi-welded - Installation, Commissioning and Maintenance
Description
(Continued)
Right (R)/ Left (L) plates
Plates are designed in such a way that they can
be used both as right and left plates by
alternately turning them 180°. Semi-welded
cassettes are not turned.
Right and left plates, Single plates:
On a right plate the ow runs from porthole 2 to
3 or reverse from porthole 3 to 2.
Standard gasket
First plate:
Special gasket
All portholes gasketed)
1
2
Head
4
3
Used on all plates
except rst
R
On a left plate the ow runs from porthole 1 to 4
or reverse from porthole 4 to 1.
The opening of the corner portholes is described
in a “plate code index”. For instance 1234 means
that all corner portholes are open. Every plate
can be identied by the gasket conguration, the
plate code index, and the plate geometry (e.g.
thermal short or thermal long geometry).
Each plate rotated
180° relative to plate
before/after
L
R
Last plate:
plate without
portholes
Follower
Connections:
1, 4: Brine 1
2, 3: Brine 2
Flow arrows shown are only indicative
Fig. 5. Single plates: Left and Right plates and flow
User Guide | Plate Type Heat Exchangers, Single plate & Semi-welded - Installation, Commissioning and Maintenance
Storage
Installation
If storing the plate heat exchanger for a longer
period of time, i.e. more than one month/30
days, the following precautions should be taken
to prevent unnecessary equipment damage:
Preferably the plate heat exchanger should be
stored inside in dry conditions at room
temperatures around 15 – 20 °C (59 – 68 °F) and
a humidity of maximum 70%.
If this is not possibly, place the plate heat
exchanger in a wooden box provided with a
lining on the inside that will prevent against
moisture penetration.
Foundation
Install the heat exchanger on a at foundation
providing sucient support for the frame.
Space
Ensure enough space around the plate heat
exchanger for servicing the unit (renewal of
plates, tightening of the plate pack).
As a rule, free space around the unit should be
1.5 to 2 x the width of the unit. See Fig. 7.
Rubber gasket material is sensitive to certain
agents and ultraviolet radiation.
• Plate heat exchangers must be stored
in rooms with no ozone producing
equipment such as electric motors or
arc-welding equipment as ozone may
destroy several rubber materials
• Plate heat exchangers should not be
stored together with any organic
solvents or acids in the room
• Do not expose the plate heat exchanger
to ultraviolet radiation
Drip tray
Replaceable plate heat exchangers involve a risk
of leakage.
It is recommended to take this into account while
installing. Preferably install a drip tray underneath
the heat exchanger to prevent leakages onto the
oor and/or harm to electrical equipment.
Screen plate
If the heat exchanger is being used with
temperatures above 60 °C or with aggressive
uids, we advise that you cover the heat
exchanger with a screen plate to prevent the risk
of human exposure to the surface and uids.
Min.
Fig. 7. Ensure enough free space for servicing the plate
User Guide | Plate Type Heat Exchangers, Single plate & Semi-welded - Installation, Commissioning and Maintenance
Installation
(Continued)
Transport and lifting
WARNING:
To prevent personal injury always use
appropriate hoisting equipment. If you
are to lift the heat exchanger itself,
straps should be used. The straps
should be placed as shown in fig. 8.
Usually the heat exchanger will be supplied
horizontally on a pallet.
The back side of the head will then be secured
to the pallet. This allows the unit to be
transported by means of a forklift truck.
Raising of the unit: see g. 8.
• Remove all tightening elements from the pallet
• Place straps around opposite bolts on each side
of the column (1)
• Lift the unit vertically from the pallet (2)
• Remove the pallet securely (3)
• Slowly lower the heat exchanger to the oor (4)
• Remove the straps at the unit bottom side (5)
• Lift one-sided in an appropriate lifting angle (6)
and follow the raising of the unit carefully.
Avoid any bumps or shocks
• Once the heat exchanger is in upright position
place the straps in the dedicated lifting eyes (7)
and lift the unit to its nal position (8)
• Remove the straps and mount the heat
exchanger securely to the oor
4
2
11
5
Fig. 8. Lifting instructions
Never lift the heat exchanger using any
other method than described above.
Never use the connections, studs or any
intermediate plates (if fitted) for lifting
(fig. 9).
User Guide | Plate Type Heat Exchangers, Single plate & Semi-welded - Installation, Commissioning and Maintenance
Piping systemFiltration
If the uid in the plate heat exchanger
contains particles larger than Ø0.5mm an inline
lter should be tted.
Installing the pipe connections
Most plate heat exchangers are intended for
counter-current ow directions, but some
specic applications require co-current ow.
Refer to name-plate for information on each
specic plate heat exchanger.
Danfoss plate type heat exchangers are
provided with various connection types
depending on size, application and
conditions.
Single plate heat exchangers come with
threaded pipe connections or studded
anges ready for counter/blind anges.
Semi-welded heat exchangers come with
factory installed welding anges. The
refrigerant side is hermetically closed by blind
plates and pressurized with nitrogen.
When connecting the piping system to
the plate heat exchanger make sure
that the piping system does not subject
the plate heat exchanger to stress or
strain.
Before connecting any piping to the
plate heat exchanger make sure to
clean and flush the piping system
thoroughly for any foreign objects.
Note:
• Identify actual ow inlets/outlets on the name
plate before commencing piping work
• Heavy piping should be supported. This will
prevent heavy forces on the plate heat
exchanger
• To be able to open/close and dismantle the
plate heat exchanger shut o valves should
be installed in all connections
• Remove anges from the plate heat exchanger
before connecting to the valve/piping system.
• Nitrogen pressurized refrigerant side must be
depressurized through the small valve in the
blind plate before removing the anges
• Always install exible connections on the
follower to prevent vibrations on the plate heat
exchanger. The exible connections also help
prevent expansion of the pipes, which could
be caused by temperature inuence
• Flexible connections must be tted
perpendicular to the header/follower
• Install vents on both sides of the plate heat
exchanger
• The vents should be tted on the highest point
in the direction of the media ow
• The installation must be tted with safety
valves according to current pressure vessel
regulations
Make sure that the piping system,
connected to the plate heat exchanger,
is secured against pressure peaks/
surges and temperature shocks!
When doing any welding in the flange/
valve/piping system make earthing to
the piping opposite of the plate heat
exchanger. Never use the heat
exchanger for earthing as plates and
gaskets might be severely damaged.
When fitting threaded pipe to the
threaded plate heat exchanger
connection make sure that the
connection do not rotate during
tightening as this might damage
internal ring gaskets. A secure
counter-hold is needed.
For studded flange connection, insert
the gaskets before bolting the blind
flanges to the end plate. Tighten the
bolts evenly - do not over-tighten as
this might damage bolts/threads.
User Guide | Plate Type Heat Exchangers, Single plate & Semi-welded - Installation, Commissioning and Maintenance
Commissioning
Commissioning, control, maintenance and repair
of the installation should be done by authorized,
trained and properly instructed sta.
Before commissioning check if all connections
are tted correctly.
Check the pressures and the temperatures of the
media and make sure they are within the limits of
the values specied on the name plate.
Start-up process
Single plate heat exchanger
For plate heat exchangers with liquid on both
sides (liquid/liquid ow) the ow with an
operating temperature closest to the ambient
temperature is to start rst, i.e.
Flow 1
Delta T to ambient temperature lowest
Flow 2
Delta T to ambient temperature highest
Start liquid flow 1 first, then liquid flow 2.
For both ows follow these steps:
• Vent the system fully
• Close shut o valve tted between pump and
plate heat exchanger
• Fully open valve tted into return line from the
plate heat exchanger
• Start the circulation pump usually placed at
the inlet
• Gradually open the closed shut o valve
between pump and plate heat exchanger
• Vent system again if necessary
The plate heat exchanger must not be
subject to thermal or mechanical shock
as this could lead to premature gasket
failure.
Check during operation
For proper and safe operation
• Check the system for potential pressure pulses
caused by pumps or control valves. In case of
pressure pulses, stop operation and rectify
• Continuous pressure pulses could cause
fatigue issues of ow plates
• Check that no leakages appear from the unit
• Check that all vents are closed to prevent air
being sucked into the system
• Check that the operating conditions including
media temperatures and pressures are within
the limitations stated on the name plate.
These must not be exceeded
When in operation the conditions
should not be changed. Media
temperatures and pressures must be
within the limitations stated on the
name plate and should not be
exceeded.
Start-up process
Semi-welded heat exchanger
For semi-welded plate heat exchangers with
refrigerant on one side and glycol/water on the
other side, the glycol/water side, i.e. the liquid
ow, must be started rst.
Start liquid flow first, then refrigerant flow.
For the liquid ow follow steps mentioned above.
For refrigerant ow follow these steps:
• Keep shut-o valves at the plate heat exchanger
connections closed, while evacuating the heat
exchanger completely
• Gradually open the shut-o valve at the outlet
for pressure equalization and subsequently
gradually open the inlet to the heat exchanger
• Activate the refrigerant system following
normal procedure
If a high pressure difference is present
and refrigerant in liquid phase in
connecting pipes, precautions should
be taken to avoid liquid hammer.
Liquid hammer may cause considerable
damage to the equipment and cause
refrigerant leakage to the ambient.
User Guide | Plate Type Heat Exchangers, Single plate & Semi-welded - Installation, Commissioning and Maintenance
Shut-down
Shut-down for a short period
If the plate heat exchanger has to be shut down
for a short period the following procedure should
be followed:
• Gradually close the inlet control valve in the
refrigerant (ow 2) circuit whilst maintaining
the full ow in the liquid circuit (ow 1)
• For high temperature applications cool down
the heat exchanger to below 40 °C ( 104 °F)
• Gradually close the inlet control valve in the
liquid (ow 1) circuit
• Switch o the liquid (ow 1) circuit pump
Shut-down for a long period
If the unit is to be shut down for an extended
period of time then the following procedure
should be followed:
• Follow steps above
• Allow unit to reach ambient temperature
• Ensure a minimum amount of refrigerant in the
heat exchanger. Boil o using ow 1 in
evaporators or use liquid drain in condensers.
• Evacuate refrigerant side
• Drain ow 1 circuit
• Lubricate threads on the tie bolts
• Loosen tie bolts according to the instruction
in “opening the plate heat exchanger” section
until the length of the plate pack reaches:
- Single plate: A-measure max. +10%
- Semi-welded: A-measure Nominal +10%
• The tie bolts should not be removed or
loosened to such an extent that dirt is allowed
to enter in-between the plates. It is
recommended to attach a warning notice to
the plate heat exchanger to remind personnel
that the tie bolts need adjustment before the
unit can be put back into service
• Cover the plate pack with black plastic to
exclude any sunlight
Maintenance
CIP cleaning
Clean-in-Place, CIP cleaning, allows cleaning the
plate heat exchanger without opening it and is
done by circulating cleaning agents in the heat
exchanger.
CIP cleaning of the refrigerant circuit is
not allowed. CIP cleaning can be done
only on the brine circuit.
The use of CIP cleaning is relevant for soluble
fouling only. Prior to CIP cleaning ensure that all
materials in the entire circulation system are
resistant to the cleaning agent/CIP liquid used.
We advise to ask for a confirmation
from the supplier of the cleaning agent
that it will not damage the materials in
the heat exchanger.
Cleaning agents guidance
Oil and grease can be removed with a water
emulsifying oil solvent.
Organic and grease cover can be removed with
sodium hydroxide (NaOH) maximum
concentration 1.5% - max. temp. 85 °C (185 °F).
Mixture for 1.5% concentration = 5 l 30% NaOH
per 100 l water.
Check maximum allowable working temperature
on the name-plate mounted on the head of the
plate heat exchanger before performing CIP
cleaning. Maximum working temperature should
not be exceeded at any time. Consult Danfoss if
in doubt.
If the solution requires recirculation, select a ow
that is as high as possible, and no less than the
service or operation ows.
Follow the instructions from the supplier of the
cleaning agent. For re-circulated cleaning, we
recommend that uid is circulated in the plate
heat exchanger for no less than 30 minutes.
Rinsing
After using any type of cleaning agent, always
rinse the plate heat exchanger thoroughly with
fresh water. After CIP cleaning, circulate fresh
water for at least 10 minutes.
Nitric acid has an build up eect on the
passivation lm of stainless steel.
CAUTION:
Nitric acid and Sodium Hydroxide may
cause injury to exposed skin, eyes, and
mucous membranes. Use of protective
eyewear and gloves is strongly
recommended.
Stone and limestone can be removed with nitric
acid (HNO₃) - max. concentration 1.5% - max.
temp. 65 °C.
Mixture for 1.5% concentration = 2.4 l HNO₃
62% per 100 l water.
User Guide | Plate Type Heat Exchangers, Single plate & Semi-welded - Installation, Commissioning and Maintenance
Maintenance
(Continued)
Opening the plate heat exchanger (continued)
• Remove all tie bolts
• Pull the follower back towards the column
• Remove the plates/cassettes one by one
without damaging the gaskets
CAUTION:
Plates/cassettes have sharp edges!
When handling plates/cassettes
always wear gloves
Fig. 11. Removal of plates
Mechanical/Manual Cleaning
• Plates/Cassettes can be mechanically cleaned
by use of water and a soft brush. Alternatively a
high pressure cleaner might be used with
caution and without abrasives
• If needed cleaning agents may be used
• Cassettes are only cleanable on the brine side
and all precautions must be taken to avoid any
water or cleaning agent entering the welded
cassettes
• Consult a cleaning specialist for choosing a
suitable cleaning agent. Ensure that all agents
used are compatible with the plate/cassette
and gasket material
CAUTION:
Some cleaning agents may cause injury
to exposed skin, eyes and mucous
membranes. Use of protective eye-wear
and gloves is strongly recommended.
Never allow any water or cleaning agent
to enter the welded side of the cassettes.
User Guide | Plate Type Heat Exchangers, Single plate & Semi-welded - Installation, Commissioning and Maintenance
Maintenance
(Continued)
Mechanical Cleaning continued
Never use a metal brush, steel wool or
sand/glass paper. This will damage the
passivation film of the plates.
Never use Hydrochloric for Stainless
teel plates. Never use Hydrofluoric for
Titanium plates.
• Always remove plates/cassettes one by one
and number them in right order
• Plates/cassettes removed for manual cleaning
must be re-tted in the same order
• Single plates may be immersed into a solvent
bath to dissolve hard fouling
Plate/Cassette replacement
If a plate/cassette has to be renewed
because of serious damage, it is
recommended to replace the plates/
cassettes next to this plate/cassette.
• Plates/Cassettes must be replaced if damaged
or not cleanable
• When ordering new plates/cassettes all data
from the nameplate is required
• New plates/cassettes are supplied with
complete gaskets ready for immediate
installation
Before fitting chemical cleaned plates
they need to be thoroughly rinsed
with fresh water!
These gaskets are mounted without the use of
any glue. They are positioned by pushing the
gasket fully down into the gasket groove or
fastened by special devices. Make sure groove
and gasket are clean.
Glue type gaskets
The surfaces need to be clean and free of oil. Only
use chloride free glues like Pliobond 20 or 30,
Bostic 1782, 3M EC 1099 and Bond Spray 77.
Follow the instructions of the manufacturer.
CAUTION:
When using commercial solvents and
adhesives, follow the manufacturers
recommendations carefully. Most of
these solvents are hazardous.
User Guide | Plate Type Heat Exchangers, Single plate & Semi-welded - Installation, Commissioning and Maintenance
cassette/plate package
cassette/plate package
Maintenance
(Continued)
Closing the plate heat exchanger
When assembling and closing the heat
exchanger observe the following:
• Check that all gaskets are correctly positioned
in the grooves
• Check that plates/cassettes are hanging
correctly on the carrying bar
• Press the plate package together by pushing
the follower
• Make sure the plates are in the correct position
according to the marked diagonal or
numbering
• Check the plate/cassette edge pattern for
uniformity (see g. 13)
• Identify the A-measure noted prior to opening
the heat exchanger (conrm with nameplate)
• Use appropriate tools and lubricant
• Ensure there is no ow to any part of the unit
• Clean the tie bolts and grease the threads
• Install the long tie bolts and tighten evenly
in the numbered order 1, 2, 3, 4 (g. 14) until a
resistance can be noticed. i.e. the follower shall
have a parallel closing motion
• Tighten the long tie bolts in sequence 1 to 4
alternately until the A-measure has been
reached at all long tie bolts
• Tighten the short tie bolts in an alternating
order until the A-measure has been reached at
all tie bolts
• Prepare for operation. Folow instructions in
section "Start-up process"
• If the heat exchanger does not seal immediately
the tie bolts can gradually be tightened to
A-measure minimum (see name plate)
The A-measure shall never be less than
A-measure minimum.
• If rollers are tted to the follower, lubricate the
bearings with light machine oil
CIP and
manual
cleaning
PHE audit
PHE audit
PHE audit
Leak
detection
refrigerant
Replace
ring- and
main body
gaskets**
Leak
detection
refrigerant
CIP and
manual
cleaning
Leak
detection
refrigerant
CIP &
manual
cleaning
Replace
ring
gaskets*
CIP and
manual
cleaning
Replace
ring
gaskets*
10
Replace
ring- and
main body
gaskets**
12
13
PHE audit
15
Fig. 15. Guideline for service intervals for semi-welded plate heat exchangers. Indicative for clean fluids/normal
conditions and dirty fluids/severe temperature-pressure conditions respectively
* Ring gasket kit
** Full gasket kit
PHE audit: Visual inspection of operating conditions, leaks, corrosion and general condition
Leak detection refrigerant: Electronic testing (sniffer)
CIP: Clean in place (See section "clean in place")
Manual cleaning: Plate pack disassembly/plate cleaning
Replace gaskets: Plate pack disassembly/replace gaskets
At extreme fluids/conditions audits should be performed more frequent
User Guide | Plate Type Heat Exchangers, Single plate & Semi-welded - Installation, Commissioning and Maintenance
Troubleshooting
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.
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.
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.
ProblemPossible causePossible solution
Check the rubber liners (if fitted)
Connection sealing damaged
Leakage
Insufficient capacity
Too high
pressure drop
Fig. 16. Summary of possible problems, causes and solutions
Mixing of primary and secondary circuit
Plate package sealing damaged
The operating conditions deviate from the
specification
Air in the system
The operating conditions deviate from the
specification
The heat exchanger is fouled internallyClean the heat exchanger
The connections have been interchangedRedo the pipe work
Flow larger than the design flowAdjust the flow
Channels in plates blockedFlush / clean
Incorrect measurementCheck the pressure indicator
Fluid deviating from the specificationCheck the chemical composition
Air in the system
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
“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.
Check the flange gasket (if fitted)
Check the ring gasket at first plate
Fit the pipes tension-free
Check the plates for holes and/or cracks
Single plate:
Semi-welded:
Check the assembly distance "A"
Check the condition of the gaskets
Check the proper position of the gaskets
Adjust the operating conditions
Vent the piping system
Check the pipe work for possible air traps
Adjust the operating conditions
Vent the piping system
Check the pipe work for possible air traps
the instructions in section "Opening the plate
heat exchanger".
Check the gaskets around the
port and diagonal areas
Check the diagonal part of the
field gasket and ring gasket
oss can accept no responsibility for possible errors in catalogues, brochures and other printed material. Danfoss reserves the right to alter its products without notice. This also applies to products
already on order pro
All trademarks in this material are property of the respec
vided that such alterations can be made without subsequential changes being necessaryeady agreed.