Zodiac - Contactor Z400 MD8/MD9 32A - B0245900

Zodiac – Contactor Z400 MD8/MD9 32A – B0245900

The Zodiac B0245900 is a genuine OEM replacement contactor designed for use with Zodiac Z400 series heat pumps, specifically compatible with MD8 and MD9 model variants. A contactor is an electrically controlled switch used to manage the high-current circuits within a heat pump — in this case rated at 32 amps — making it a critical safety and operational component responsible for switching the compressor and other high-load elements on and off under the direction of the control board. Without a properly functioning contactor, the heat pump cannot start or maintain its heating cycle reliably.

This contactor operates at a 32A rating, which corresponds to the higher-capacity requirements of the MD8 and MD9 models within the Zodiac Z400 range. Contactors of this type typically feature electromagnetic coil activation, durable contact blocks rated for repeated switching cycles, and robust construction suited to the demanding electrical environment inside a pool heat pump enclosure. As a Zodiac genuine spare part, this component is manufactured to the same specification as the original fitted unit, ensuring correct fitment, reliable contact resistance, and full compatibility with the Z400 control system.

Compatibility and installation context

The B0245900 contactor is specifically listed for the Zodiac Z400 MD8 and MD9 heat pump models. The Z400 series is Zodiac’s established range of residential pool heat pumps, designed for in-ground and above-ground pool heating applications across a broad range of pool sizes. This part is intended for qualified technicians or electrically competent service personnel, as replacement of internal electrical switching components requires isolation of the unit from mains supply and adherence to all relevant electrical safety standards. Installation should always be carried out in accordance with the Z400 service documentation and applicable local electrical regulations.

Suitability and buying context

This replacement contactor is the correct choice if your Zodiac Z400 MD8 or MD9 heat pump is exhibiting symptoms such as failure to start, intermittent compressor operation, audible clicking without the compressor engaging, or visible burn damage to the existing contactor. Sourcing a genuine Zodiac spare part ensures that the replacement matches the original electrical rating and physical configuration, avoiding the risks associated with non-specified alternatives. If you are unsure which contactor variant your unit requires, always cross-reference the model designation on your heat pump’s data plate before ordering, as alternative Zodiac Z400 variants use different contactor ratings (such as the 12A R0815500 for TD7/TD8 models).