Danfoss XG Heat Exchanger Service and Repair Instructions

Safety Notes

⚠️ To avoid injury of persons and damages to the device, it is absolutely necessary to carefully read and observe these instructions.

Necessary assembly, start-up and maintenance work must only be performed by qualified and authorized personnel.

Cleaning the Heat Exchange Plates

Backwash

The backwash removes fouling that has accumulated on the surface of the plate. Clean water is flushed with high speed into the primary and / or secondary side in the opposite direction from the one used during normal operation.

The heat exchanger can also be washed with a cleaning compound, approved by Danfoss (e.g. Kaloxi® or Radiner FI liquid cleaner concentrate), which is environmentally friendly and can be disposed of through a normal sewer. After using a cleaning compound, the heat exchanger must be flushed thoroughly with fresh water.

Manual Cleaning

Note: You cannot open the brazed heat exchanger.

Do not damage the heat exchange plates gasket during cleaning.

Detach the heat exchange plates from the heat exchanger for cleaning. Clean the plates with a soft brush and running water. If the dirt does not come off the plates easily, you can use a cleaning compound. After use of the cleaning compound, the heat exchange plates must be rinsed completely with clean running water.

Opening the Gasket Heat Exchanger

Wait for the heat exchanger's temperature to fall below +40 °C before opening the heat exchanger.

1. Drain the heat exchanger.
2. Mark the order of the exchange plates by drawing a diagonal line to the exchanger.
3. Measure and note the heat exchanger's measurement (tightening measurement A).
4. Loosen and detach the exchanger's tightening bolts.
5. Open the plate pack by moving the end plate. Detach the heat exchange plates carefully from each other.

Gasket Replacement

XG 10 Gaskets

1. Remove the old gasket.
2. Place the new gasket into the groove. The plate is ready for mounting to the heat exchanger.

Clip-on Gaskets

For XG 14, XG 18, XG 20, XG 31, XG 40, XG 50.

1. Remove the old gasket.
2. Place the new clip-on gasket into the groove and fasten it with the aid of the clip. The plate is ready for mounting to the heat exchanger.

Glued Gaskets

For XG heat exchangers except for XG-10 and ones equipped with clip-on gaskets.

1. Remove the old gasket.
2. Clean the gasket groove carefully (note the safety aspects when using e.g. thriclorethylene).
3. Apply the glue into the gasket groove and let it dry for about 10 minutes.
4. Place the gasket into the groove and let it dry for about 1 hour. After drying, the plate can be mounted to the heat exchanger.

Reassembling the Heat Exchanger

Before reassembly, check that the sealing surfaces are clean and the gaskets are securely attached to the heat exchange plates.

1. Mount the plates in the opposite order from that used in dismantling, with the gasket side of the plate towards the front end plate.
2. Check that adjacent plate profiles are in opposite directions (see the plate diagram).
3. Press the plates against each other and start the tensioning of the plate back by tightening the bolts evenly (start tightening from center to outwards, see the numbering). Ensure that the end plates are parallel at all times.
4. Continue tightening until the heat exchanger's measurement A (tightening measurement) is achieved.
5. The tightening measure is correct when the crests of the plates are in metal contact with each other. Excess tightening can cause changes in the plate profiles.