Hot tub starts on its own?

[green2012]

Had a costomer call over the weekend and say that his house experienced a surge or blackout (probably both). He knew this because all his clocks and displays were blinking. The problem was that his hot tub started on its own. Going over tomorrow to take a peak and wanted some advice. I have never heard of a hot tub starting on its own when the tub was empty. He says that it has happened more then once and both times he experienced a blackout. Can the inrush of power from service being restored start a motor? Does this indicate any red flags that im not thinking off?

 

[Sierrasparky]

There is a Electronic control unit Who's to say what can happen to it to cause the unit to turn on by itself.

Gremlins I say.

 

[CONDUIT]

I would contact the tech department of the hot tub manufacturer and ask them!

 

[kwired]

The "brownout" is not starting the motor, but may be causing the (most likely solid state) controls to operate in an undesired way. Maybe the spa manufacturer is aware of this problem and has a fix for it.

 

[Sierrasparky]

Please let us know what you find out.

 

[HotTubTips]

Tub starts by itself

Tub starts by itself

Had a costomer call over the weekend and say that his house experienced a surge or blackout (probably both). He knew this because all his clocks and displays were blinking. The problem was that his hot tub started on its own. Going over tomorrow to take a peak and wanted some advice. I have never heard of a hot tub starting on its own when the tub was empty. He says that it has happened more then once and both times he experienced a blackout. Can the inrush of power from service being restored start a motor? Does this indicate any red flags that im not thinking off?

If the tub is empty, the power should be turned off at the maintenance disconnect and/or the main breaker.

If the power was left on, the tub should detect it is empty and throw an error code that shuts down the pumps and heater. The tub will be 'shut down' for all intents and purposes but will still have 220V and an error code on the digital display. It should pull less than 1 Amp in this state.

If the power is reset, the tub will reboot, perform it's self test and attempt to restart until it triggers another empty-related error condition. The restart cycle often includes automatically turning on pumps and other components. If the tub is empty, it may go through this restart cycle four or five times before it triggers a 'hard error code' that can only be cleared with a power reset.

I would bet the tub behavior is not the cause before the power outage but the effect of the tub rebooting after the power outage.

I have seen lots of tubs take some pretty good power hits including one that had a hot Neutral while the power company repaired lines after a storm. Every electronic component in the house with the hot neutral was fried. The tub was 100% operational.

If nothing else, it sounds like they don't use the tub. Pull the disconnect or turn off the breaker and take the tub out of the equation.

 

[Sierrasparky]

That is some great troubleshooting advise.
Thanks.



Wow and this is my 3,000 post

 

[kwired]

If the tub is empty, the power should be turned off at the maintenance disconnect and/or the main breaker.

If the power was left on, the tub should detect it is empty and throw an error code that shuts down the pumps and heater. The tub will be 'shut down' for all intents and purposes but will still have 220V and an error code on the digital display. It should pull less than 1 Amp in this state.

If the power is reset, the tub will reboot, perform it's self test and attempt to restart until it triggers another empty-related error condition. The restart cycle often includes automatically turning on pumps and other components. If the tub is empty, it may go through this restart cycle four or five times before it triggers a 'hard error code' that can only be cleared with a power reset.

I would bet the tub behavior is not the cause before the power outage but the effect of the tub rebooting after the power outage.

I have seen lots of tubs take some pretty good power hits including one that had a hot Neutral while the power company repaired lines after a storm. Every electronic component in the house with the hot neutral was fried. The tub was 100% operational.

If nothing else, it sounds like they don't use the tub. Pull the disconnect or turn off the breaker and take the tub out of the equation.

I don't know for certain, but I am guessing when he said "never seen one start by itself when empty", he may have just meant when there is no users, but otherwise yes if there is no water in it, by all means disconnect the power to it.

 

[Jraef]

If the tub is empty, the power should be turned off at the maintenance disconnect and/or the main breaker.

If the power was left on, the tub should detect it is empty and throw an error code that shuts down the pumps and heater. The tub will be 'shut down' for all intents and purposes but will still have 220V and an error code on the digital display. It should pull less than 1 Amp in this state.

If the power is reset, the tub will reboot, perform it's self test and attempt to restart until it triggers another empty-related error condition. The restart cycle often includes automatically turning on pumps and other components. If the tub is empty, it may go through this restart cycle four or five times before it triggers a 'hard error code' that can only be cleared with a power reset.

I would bet the tub behavior is not the cause before the power outage but the effect of the tub rebooting after the power outage.

I have seen lots of tubs take some pretty good power hits including one that had a hot Neutral while the power company repaired lines after a storm. Every electronic component in the house with the hot neutral was fried. The tub was 100% operational.

If nothing else, it sounds like they don't use the tub. Pull the disconnect or turn off the breaker and take the tub out of the equation.

This is EXACTLY how my hot tub works. I empty the water 4 times a year to do a thorough cleaning and I kill power to the tub while doing that. I discovered that if I turn power on BEFORE I refill the tub (brain fart), it does exactly that; it cycles through 3 starts before it decides that the sensor is not telling lies. I would imagine that's because it doesn't really sense the height of the water, only that there is flow through the pipe. So as with any flow sensor, you have to have a time delay on it to allow starting, then after the pump has started you make sure there is flow. No flow after the time delay, shut down. I imagine that it does it 3 times because it wants to make sure it isn't a false negative reading on the flow sensor, otherwise if there is water in it and the pump DOESN'T turn on, it rapidly becomes a cesspool.

If the tub is empty, ie no water in it, they should not leave power on it.

 

[kwired]

This is EXACTLY how my hot tub works. I empty the water 4 times a year to do a thorough cleaning and I kill power to the tub while doing that. I discovered that if I turn power on BEFORE I refill the tub (brain fart), it does exactly that; it cycles through 3 starts before it decides that the sensor is not telling lies. I would imagine that's because it doesn't really sense the height of the water, only that there is flow through the pipe. So as with any flow sensor, you have to have a time delay on it to allow starting, then after the pump has started you make sure there is flow. No flow after the time delay, shut down. I imagine that it does it 3 times because it wants to make sure it isn't a false negative reading on the flow sensor, otherwise if there is water in it and the pump DOESN'T turn on, it rapidly becomes a cesspool.

If the tub is empty, ie no water in it, they should not leave power on it.

I have an older hot tub with no electronic controller - just a pneumatic operated switch to turn on the jets, heating cycle is thermostat controlled by a capillary tube type thermostat with dry contacts. Pump will start with no water, but pressure must be sensed before heat element will be energized. I kind of like it being simple and it is easier to maintain IMO.

 

[MicawberSchism]

I think this can be assisted by a hot tub guy. I had never heard about automatic starting of electronic appliances as a result of 'blackout'. But there are chances for reduced performance at the time of power fluctuation.

I have a doubt with the hot tub heater working. It is the arctic Yukun tub I have from last three years. From last week, the water temperature was dropping in my tub while in use. Putting the hot tub cover (its new) back on, the temperature slowly gets back to the set point (24hr+), but will drop quickly if the cover is off (a degree drop in <15mins). What is the reason for this and how can I clear this off?

 

[MicawberSchism]

I think this can be assisted by a hot tub guy. I had never heard about automatic starting of electronic appliances as a result of 'blackout'. But there are chances for reduced performance at the time of power fluctuation. I have a doubt with the hot tub heater working. It is the arctic Yukun tub I have from last three years. From last week, the water temperature was dropping in my tub while in use. Putting the hot tub cover (its new bought from The Coverguy) back on, the temperature slowly gets back to the set point (24hr+), but will drop quickly if the cover is off (a degree drop in <15mins). What is the reason for this and how can I clear this off?

 

[GoldDigger]

I think this can be assisted by a hot tub guy. I had never heard about automatic starting of electronic appliances as a result of 'blackout'. But there are chances for reduced performance at the time of power fluctuation. I have a doubt with the hot tub heater working. It is the arctic Yukun tub I have from last three years. From last week, the water temperature was dropping in my tub while in use. Putting the hot tub cover (its new bought from The Coverguy) back on, the temperature slowly gets back to the set point (24hr+), but will drop quickly if the cover is off (a degree drop in <15mins). What is the reason for this and how can I clear this off?

The heater is no longer producing its rated heat output. If there are two resistive elements in it, one may be open circuited, for example.
You can measure the current with a clamp-on ammeter or disconnect the heater and measure the heating elements with an ohmmeter and compare to the values in the service manual.
Once you identify the problem you can either repair or replace the heater.
It is less likely but possible that there is a problem with the wiring or thermostat which is preventing the heater from getting full voltage.

Good luck.

 

[kwired]

I think this can be assisted by a hot tub guy. I had never heard about automatic starting of electronic appliances as a result of 'blackout'. But there are chances for reduced performance at the time of power fluctuation. I have a doubt with the hot tub heater working. It is the arctic Yukun tub I have from last three years. From last week, the water temperature was dropping in my tub while in use. Putting the hot tub cover (its new bought from The Coverguy) back on, the temperature slowly gets back to the set point (24hr+), but will drop quickly if the cover is off (a degree drop in <15mins). What is the reason for this and how can I clear this off?

May depend on tub design. I have a small tub (maybe only holds 250-300 gallons) that is only supplied with 120 volts and has a 5-15 cord end (factory installed) for the supply. The heater is 1000 watts. It does not heat while in use as that would draw too much current for a 15 amp supply circuit. Is not all that big of a deal IMO because you are not supposed to sit in there for more than 20-30 minutes anyway.