Identifying Problems with Your Hot Tub Motor

The hot tub motor that drives the pump is the heart of your hot tub. When it is not working properly, the hot tub does not provide a good experience. Identifying a problem with the motor is often easy but sometimes requires a little detective work. The following will help you diagnose what's wrong with your hot tub motor.

The Motor Will Not Start

Always check the obvious. Make sure that the power supply is active and that all switches are ‘on’. Use a mains tester to check that there is power arriving at the pump.

If the pump makes a brief humming noise this will warn you that the pump has an obstruction or the motor is damaged. You will have to check the pump and motor.

The Pump Starts but Then Runs Intermittently

This is probably a sign that the motor is over heating. Make sure that there is enough water in the tub for proper cooling of the motor. There is also the possibility of mains power interruptions so check other electrical equipment to see if that shows the same symptoms.

Excessive Noise

A pump that is not fully submerged will sound a lot noisier and will probably damage itself. Make sure the water level is high enough to cover the pump. The bearings on the central shaft of the motor do wear. When these bearings start to break down, they become noisy. You will need to examine the bearings and replace any that are worn or replace the motor.

Pump Will Not Operate

If the pump is running but not actually pumping water the pump is probably air locked. This often happens when a hot tub has been drained and refilled. Usually it can be fixed simply by loosening the connection from the pump to the tub and letting the air bleed out.

The Flow Rate and Filter Pressure Are Low

The cause of this problem is often that the water level in the tub has been allowed to fall too low. The problem can also be caused by a blockage in the pump impellor which will have to be cleared.

On rare occasions this will be caused by a leak in the suction line allowing air to mix with the water. Locating the leak can be difficult while the pump is working, so check for this with the pump off. With luck, you will see water leaking from the pipe.

The Flow Rate is Low and the Filter Pressure is High

This is usually caused by a dirty hot tub filter. Cleaning or changing the filter is all that is required.

If some of the jets show high pressure it is possible that those showing low pressure are blocked. Check them and clean them out where necessary. Try to find out where the blockage came from to prevent a repetition.

Water Leaks around the Pump

This can be caused by worn ‘O’ rings on the pump or loosening of the plumbing connections. You will need to identify exactly where the water is coming from. Tighten up the plumbing or replace the ‘O’ rings.