Dirt separator for heat pumps Termojet Dn25 (G1")

Termojet DN25 magnetic dirt separator — a specialized device for protecting heat pumps against magnetite and other contaminants. Connection DN25 (G 1"), flow capacity 2,7 m³/h, maximum temperature 110°C, pressure 10 bar, body — composite/brass. Built-in shut-off valves and a drain valve allow servicing without draining the heat transfer fluid from the system.

Why a heat pump needs a magnetic separator

Heating systems accumulate magnetite over time — Fe₃O₄, a black ferrous sludge that forms during corrosion of steel radiators, pipes, and expansion tanks. For a conventional boiler this is a slow problem. For a heat pump — it is critical. The HP plate heat exchanger has narrow channels (0,5–2 mm) where magnetite gradually accumulates and blocks the flow. Thermal conductivity drops, the HP enters fault mode, and the cost of replacing the heat exchanger starts from tens of thousands of hryvnias. A conventional dirt separator does not retain magnetite — a powerful permanent magnet is required.

How it works

The heat transfer fluid passes through the separator chamber, where the flow velocity decreases. A powerful neodymium magnet inside the body "pulls" magnetite particles out of the flow — they adhere to the magnetic rod and accumulate. At the same time, gravitational separation settles non-magnetic particles — sand, rust, mechanical sludge. For cleaning: open the shut-off valves, remove the magnetic rod, wipe off the black magnetite deposit, reinsert — the procedure takes a few minutes without fully draining the system.

Technical specifications

Where and how it is used

Installed on the return pipe directly before the heat pump heat exchanger. This is where all particles are intercepted before they enter the narrow channels of the heat exchanger.

• Air-source heat pump. An air-to-water system with radiator heating or underfloor heating — magnetite from old steel radiators is the main risk to the heat exchanger.
• Geothermal heat pump. A closed ground loop can also introduce corrosion products — the magnetic separator protects the heat exchanger from both sides.
• Bivalent system (HP + boiler). The boiler additionally generates corrosion products during operation — the separator protects the HP heat exchanger from contamination on the boiler circuit side.
• New system with radiators. During the first months of operation the system releases the maximum amount of magnetite — that is when the separator is most important.

More about heat pump systems and equipment selection — on the Termojet heat pump website.

Advantages

• Neodymium magnet — the only effective way to capture Fe₃O₄ magnetite from the heat transfer fluid.
• Shut-off valves included — servicing without draining the entire system and without stopping the HP for a long time.
• Combination of magnetic and gravitational separation — retains both magnetic and non-magnetic particles.
• The cost of the separator is incomparably lower than the cost of repairing or replacing the HP heat exchanger.

Related products

If the system also requires air removal — supplement the protection with the combined Air and Dirt Separator DN25. For standard dirt protection without a magnet — Dirt Separator DN25. Full range — Termojet Separators — catalogue.