Hot Tub Pump Not Turning On? No Power or Dead Display — Here's How to Fix It

You go to switch the tub on and… nothing. No lights, no display, no hum from the pump — it's completely dead. It's one of the more alarming faults because it feels terminal, but in our experience across Bournemouth, Poole and Christchurch, the most common causes of a totally dead pump are external — the plug, the socket or a tripped safety device — not the pump itself. Those you can often fix in five minutes without spending a penny.

This guide covers all brands — Lay-Z-Spa (AirJet and HydroJet), Intex PureSpa, MSPA, CleverSpa and hardshell hot tubs. Work through it top to bottom: the free, safe checks come first, the engineer-only faults last.

⚠️ Safety first A dead pump combined with any sign of water around the plug, scorching, or a burning smell means stop and unplug immediately. Do not keep resetting a device that trips repeatedly — an RCD trips to protect you from a real fault. Never open the pump housing: hot tub pumps run at mains voltage and hold charge even when unplugged.

Quick Checks First (5 Minutes, No Tools)

1. Reset the RCD / GFCI on the Plug

Almost every UK hot tub plugs in through a large moulded RCD plug (the chunky block with TEST and RESET buttons). This is a safety cut-out that kills all power the instant it senses a fault or a nuisance trip. If it has tripped, the pump is completely dead. Press RESET firmly — you should feel and hear it click in. If the display springs back to life, you're done.

If it trips again straight away, that's telling you something: either the plug itself has failed (very common after a season outdoors) or there's a genuine fault in the pump drawing current to earth. Don't keep forcing it — note it and move on to the checks below.

2. Confirm the Socket Actually Has Power

Plug a phone charger, lamp or any known-good appliance into the same socket. No power? Check your consumer unit (fuse box) for a tripped breaker and reset it. Hot tubs draw up to 13A, so a heavily loaded circuit can trip — ideally a tub runs on its own dedicated outdoor circuit. Avoid extension leads, reels and cheap outdoor adaptors — they're a leading cause of intermittent power loss and are a genuine safety risk on a 13A continuous load.

3. Inspect the Plug and Cable

With the plug pulled out, look closely for:

Water ingress inside the RCD plug or socket — by far the most common cause in Bournemouth's damp coastal weather. Let it dry fully before retrying.
Scorch marks, melted pins or a burning smell — stop using it; the plug needs replacing by a competent person.
Damage to the cable — cuts, crush points (patio furniture, garden tools) or rodent damage over winter.

A failed RCD plug is a recognised, replaceable fault on Lay-Z-Spa and Intex pumps — it does not always mean the pump is dead.

If the Pump Was Running and Then Cut Out

Overheat Thermal Cut-Out

If the pump went dead while running — especially on a hot day or after long use — the thermal cut-out may have tripped to protect the motor. The fix is patience: unplug the pump and leave it to cool for up to two hours, keep it out of direct sun, then plug back in. If it powers up, it overheated; improve ventilation and don't run it back-to-back in the heat.

Tripping the House Electrics Repeatedly

If switching the tub on trips your whole fuse box or RCD every time, that's a separate (and more serious) fault — usually water in the heater element or pump. We cover this in detail on our hot tub tripping the electrics guide. Don't keep resetting it.

If the Supply Is Good But the Pump Is Still Dead

Blown Internal Fuse

Some pumps contain an internal blade or glass fuse that blows to protect the electronics. A blown fuse leaves the pump totally dead. While it can be replaced, a fuse rarely blows for no reason — if a new one blows again, there's an underlying fault (heater, transformer or board) that needs diagnosing. This is engineer territory.

Failed Control Board (PCB) or Transformer

If the socket has power, the RCD plug holds in and is undamaged, but the display stays black and the pump won't respond, the fault is most likely inside the pump — typically the control board (PCB) or the low-voltage transformer that powers the display and buttons. A dead transformer is a classic "everything is fine but nothing turns on" symptom. Diagnosing this needs a multimeter and should be left to a qualified engineer.

💡 Tip: rule out the plug before condemning the pump If you can safely borrow or buy a compatible replacement RCD plug for your model, swapping it is the cheapest test there is. A surprising number of "dead pumps" are simply a failed plug — far cheaper than a new pump or a call-out.

Pump Still Dead After the Checks?

If the supply is good and the plug is sound but the pump won't wake up, it's a board or transformer fault — time for a local engineer. We'll match you with someone who knows your brand.

📞 Get a Free Quote

How Much Does a "No Power" Pump Repair Cost?

Typical costs in the Bournemouth area for a pump that won't turn on:

Resetting the RCD / drying out a damp plug: £0 (DIY)
Replacement RCD plug / power cable: £15-40 part
Internal fuse replacement: £5-20 + labour
Transformer replacement: £30-80 + labour
Control board (PCB): £80-200 + labour
Typical engineer call-out: £40-80 (often includes the first 30 mins of labour)

Many "dead pump" jobs turn out to be a £15-40 plug — well worth checking before assuming you need a new pump (£200-400+) or, worse, a whole new tub.