Common Causes of Flow Error in Hot Tubs and How You Can Remedy Them

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Among the most common hot tubs service calls in Vancouver or elsewhere are about spas that are not heating, mostly due to a flow error. Many times, spa owners do not know that their tubs have a low flow error since the only indication is a temperature that is below the desired level. While it’s best to call your supplier to service your unit, it’s beneficial to know what causes the problem so you can prevent it in the first place.

What Is a Hot Tub Flow Error?

On each side of your spa’s heater, there are two devices that read the water pressure flowing through the system. You could also have a pressure switch that is located on your heater and has the same functions as the two sensory devices. These sensors help protect the heater from running dry. When the water flow goes down to dangerous levels, the sensor directs the system to shut down to avert a burnout. If the flow is not at the desired level, there is usually a generous amount of air in the lines, indicating that the system is running dry.

flow error

Causes of Hot Tub Flow Error

The most common causes include dirty filters, low water levels, bad flow sensors, and clogged circulation pumps. Filters are the number one culprits of spa flow errors. Since some users do not often clean their cartridges, the pleats get clogged, which restricts water flow. The water level is another common factor in flow errors. Even if there is an insulating cover, there could be high levels of evaporation, which could lead to a lot of water loss. When the water level goes down to a certain level, and the filter is not completely submerged, it could cause air to be drawn into the system, thus giving you a low flow error.

Troubleshooting Flow Errors

After the water levels in your spa are checked and found to be too low, a repair technician that specialises in hot tubs will turn it off at the GFI, then fill it and turn it back on. If the level of water is not the problem, however, the filter cartridges should be removed. After a minute or so, the error should clear itself. If this is not the case, the tub should be switched off at the GFI breaker and then turned on after a minute. This process will clear the error, which should be an indication that the filters need some cleaning or replacement.

The sensors should also be checked to determine whether they are producing a false error. If so, they should be replaced.

The circulation pump in your spa could be clogged by debris, which could cause a low flow. However, if the pump is not in its right condition, you can hear a whining sound when it is running. The sound could mean a bad motor or a clogged impeller.

Hot tub low flow is a common problem that can be quickly diagnosed. Tubs are designed in such a way that, when there is inadequate water flow, they switch off to avoid potential damage. However, just like any other house hold item, proper maintenance can prolong the life of a hot tub.


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