Pallas EF300 and EF500 Replacement Transformer

WrekinWater stocks this replacement mains transformer for Pallas EF300 and EF500 reverse osmosis systems, supplying the low-voltage power that runs the booster pump control unit. It's a straightforward like-for-like swap when the original transformer has failed or stopped powering the system.

Signs this needs replacing

• The booster pump doesn't run at all, despite the wall socket being confirmed live.
• There are no indicator lights showing on the EF300 or EF500 control unit.
• The pump hums faintly but never starts properly, suggesting power below what it needs.
• The transformer casing feels warm or hot, or shows visible damage.

This transformer steps down your mains electricity to the low-voltage supply that drives the EF300/EF500 booster pump's control electronics. Internal winding faults, a blown internal fuse or a heat-damaged casing can all cut power to the whole pump circuit, leaving the system unable to boost pressure to the membrane even though everything else is connected correctly.

As a family run business, UK Company No. 11000488, with an Excellent Trustpilot rating and more than 50,000 customers served over 15 years, WrekinWater stocks the specific transformer your Pallas EF300 or EF500 system needs, alongside major brands such as Pentair Fleck, Autotrol, Clack and Kinetico.

How to replace it

1. Switch off and unplug the EF300/EF500 system from the mains socket.
2. Disconnect the low-voltage lead running from the old transformer to the control unit.
3. Remove the old transformer from the wall socket.
4. Plug in the new transformer and reconnect the low-voltage lead.
5. Restore mains power and check that the control unit and booster pump respond normally.
6. If the pump still doesn't run, have a qualified water treatment engineer check the wiring and switches beyond the transformer.