Dolphin power supply overheating

dolphin

The Problem

A Dolphin power supply that becomes very hot to the touch, shuts down mid-cycle, or cuts power repeatedly is entering thermal protection mode. The PSU has a built-in temperature sensor that shuts the unit off when it exceeds its safe operating temperature. This is almost always caused by direct sun exposure or poor ventilation — not a fault with the unit itself.

Steps

1
Move the PSU immediately to a shaded, ventilated location. Allow it to cool for 30–60 minutes before attempting another cycle.
💡 A cool PSU is warm to the touch but not hot. If you cannot hold your hand on it, it is too hot to run.
2
Confirm there is open airflow on all sides of the PSU — at least 15cm clearance around the casing.
3
Run a cycle from the shaded location. If the PSU stays cool and completes the cycle, sun exposure was the cause.
4
If the PSU overheats even in shade at normal ambient temperature, check whether the unit has an internal fan and listen for it running during operation.
5
For hot climates, schedule robot cycles for early morning or evening to reduce ambient temperature stress on the PSU.

Possible Causes & Solutions

common

PSU placed in direct sunlight during operation

Move the PSU to a shaded location — under a sun umbrella, in a pool house, or in the shade of the pool equipment. The PSU is not weatherproof against direct sun heat and will regularly trip its thermal protection in full sun.

common

Insufficient airflow around the PSU

Do not place the PSU in a sealed box, wrapped in a towel, or against a wall without airflow on all sides. The unit needs air circulation around the casing to dissipate heat.

occasional

Ambient temperature too high for extended operation

In very hot climates (above 40°C ambient), even a shaded PSU may overheat during long cycles. Run the robot early morning or evening, or use the shortest cycle time appropriate for your pool.

rare

Internal PSU fan failure (on fan-cooled models)

Some larger Dolphin PSU models include an internal cooling fan. If the unit overheats even in a shaded, ventilated location, the internal fan may have failed. This requires professional service.

When to Replace

A PSU that overheats in shade and normal temperatures may have a failed internal cooling component. Contact Maytronics support — do not replace until the root cause is confirmed.

Where to Buy

Find compatible replacement parts from these retailers:

Check price for dolphin replacement parts on Amazon

Frequently Asked Questions

Is it safe to run the PSU when it is hot to the touch?

No. A PSU that is too hot to hold has triggered or is about to trigger thermal protection. Let it cool fully before running another cycle — operating above thermal limits can cause permanent damage.

Can I use a fan to cool my PSU?

Yes. Placing a portable fan to direct airflow across the PSU is a practical solution in very hot environments. This does not harm the unit.

Why does my Dolphin work in the morning but not in the afternoon?

This is a classic thermal shutdown pattern. The PSU heats up as ambient temperature rises through the day. Running the robot in the morning avoids the hottest part of the day and prevents thermal shutdown.