I am hoping someone can help me out. I have been searching the posts here but haven't seen my exact situation.
The tub is a Hot Springs Spa, (Watkins) Classic F
S/N: F351072
120V 14.4A 60hz
Heater: Vulcan KF F9 ? 1500W 120V Watkins 34798-F

On Sunday, 2/18, we temporarily unplugged our tub. We plugged it back in and soaked that night with jets in 102 degree water. I returned to the tub 1 or 2 evenings later and it was only 95 degrees. Now six days later the tub is 78 degrees. It seems to be loosing heat slowly.

I have checked the thermostat - it clicks when turned down and up.
I cannot find the heater reset button referenced in other posts.
I do not feel any water movement from the bottom of the tub where the heat usually enters the tub. This makes me suspect the circulation pump.
I have removed al 3 filters to be sure they are not clogged and causing the problem. But without finding the reset button I don't know what good it does.
The light on the control panel is glowing solid red and as I said the jets are working.
The tub is well covered with a 1 year old factory made cover.

I have some electrical knowledge and a multimeter if I can just get instruction on where to check and what to check for I ought to be able to trouble shoot the problem. I have not dropped the black box out of the tub to see if the board has any burn marks on it. Is that the next step or should I take some meter readings?

Thanks for your help
Jon

Check circ pump flow, and check for dirty filters. You don't have a reset button on your heater.

It's possible the element is bad, but don't replace it unless you are SURE it's broken.

More likely a bad circ pump or flow switch-maybe even a heater relay.

After cleaning you rfilters and checking for good circ pump flow, next step in troubleshooting is to pull out your electrical meter, are you ready for that?

Swine,

What is the best way to check the circ pump? I don't feel flow?

Can you describe the terminals I need to check with the meter and the results I would expect.

Thanks

Well, you can physically feel the water flowing though the outlet (Which doubles as the floor drain in inside of the tub) Remove the grill, and check for flow. It's very slow, about 2 gallons or so a minute.

Also, unplug the flow/switch harness on the side of the control box, and check resistance on the flow switch. It's the bottom receptacle, the other two are thermistors.
Typing in a hurry- if I'm being unclear- just ask

There is definitely no flow through the bottom drain.

The circuit is open when I test the flowswitch on the wire side after disconnecting from control box. That is to say the ohm meter doesn't move. I think that is what you wanted me to test.

Thanks again for your help
Jon

If the filters are good and clean, grab a new circ pump, install- you'll be good to go

Thanks Swine. That was the solution. I appreciate your help.

I posted a new topic, but I thought this may be part of my problem, I know the circ pump is good, so I think is either heater element, thermostats, or flow switch, if I check the resistance on the flow switch, if good should it have 0 resistance?