[jbpsrc763]

Just powered up 2010 Jacuzzi J335 hot tub after 9 months off. Got FL1 error (everything else worked (jets, lights, etc)), so turned off breaker several times while troubleshooting. Now control panel remains dark, no signs of life.
Opened up hot tub electrical service box, and used multimeter to test 3 wire 240v at Terminal Block. Red(1) + Gnd(3) = 115v; Black(2) + Gnd(3) = 115v. So far, so good. To test for 240v, I touch probes to both hot legs (Red(1) and Black(2)) simultaneously. Should get 230v, but instead get weird variable 2-12v readings. I do same test on circuit board at Transformer and Circ Pump (16/17), and get same results.
Am I doing something wrong in my test? Is my meter malfunctioning? Or is this some weird power problem coming into the tub?
I probably have dead Circ Pump (original FL1 error), and maybe dead Control Panel or Circuit Board now. But I want to understand if my power is OK 1st before I start buying parts for other fixes.
Thoughts?

 

[SW Dweller]

Have you tripped the breaker feeding the spa?

 

[Jim Port]

Check for 240 at the disconnect.

 

[C'est Moi]

You will get 120v from each hot to ground but that doesn't mean you will get 240V across the hots. My bet is one leg is dead and you are reading voltage thru the windings of the heater to get 120V on the other leg.

Try resetting the gfci or the other breaker and try again. If that doesn't work test the voltage at each breaker

 

[bill.macdonald]

Make the same checks with the load disconnected. Turn off at breaker before removing wiring. After disconnection and wiring not touching anything or each other, make your checks. If you get your "normal 120/120/240 readings, the problem is in your tub. As others have suggested, the funky readings are due to faulty boards, wiring etc.

 

[jbpsrc763]

Ahh... seem to be narrowing in on the problem (thanks Jim Port! . At the gfci breaker at the emergency disconnect box for the hot tub, it appears the gfci breaker itself is faulty.
Input to the breaker tests properly: with multimeter probes at: Leg 1 (1) + Gnd (3) = 118v; Leg 2 (2) + Gnd (3) = 118v; Leg 1 (1) + Leg 2 (2) = 235v.
However, output from the breaker fails test, just like at hot tub: with multimeter probes at: Leg 1 (4) + Gnd (3 or 6) = 118v; Leg 2 (4) + Gnd (3 or 6) = 117v; but when testing both hot legs: Leg 1 (4) + Leg 2 (5) = 3v.
So it sounds like something is broken inside the gfci breaker which does not let the 2 legs parallel together to give me 240v output.
I'm new to electrical, haven't read about this type of problem before.
But I presume just replace the gfci breaker should be the solution?
Thanks!

 

[flyingron]

Next thing to try. TURN OFF the breaker. Disconnect al the load wires from it.
Turn it on, measure the voltage.

If she no work now, then it's likely the breaker.
If she do, I bet you have a legitimate ground fault somewhere.

 

[seharper]

As FlyingRon advises, always test any GFCI by removing the wires from the "Load" terminals. In this case, that means wires 4, 5 and 6. Yes, really. The Load neutral. Really.

People are used to thinking like neutral is inert or irrelevant or something, but it's a full player. We just don't bother switching it most of the time because it's (supposed to be) near 0 volts.

However do not disconnect the curly pigtail, as the GFCI needs that to power its own internal stuff, so of course it won't work without that LOL.

 

[jbpsrc763]

Thanks folks. great tips to help a newbie.
I disconnected all load wires (4, 5, 6), and retested
Input to the breaker still tests properly: with multimeter probes at: Leg 1 (1) + Gnd (3) = 118v; Leg 2 (2) + Gnd (3) = 118v; Leg 1 (1) + Leg 2 (2) = 235v.
Tests on the output from the breaker still fails: with multimeter probes at: Leg 1 (4) + Gnd (3) = 118v; but now Leg 2 appears dead: Leg 2 (5) + Gnd (3) = 0v; and when testing both hot legs: Leg 1 (4) + Leg 2 (5) =~ 90v.
So it looks like Leg 2 inside the gfci breaker is dead. And the spurious readings I get when I test the 2 hot legs is some type of loop being fed only by Leg 1 (when the loop is short (with hot tub load disconnected, I get about 90v, when the hot tub is connected, some resistance thru the hot tub is knocking this down to about 3-12v.
So time to replace the gfci breaker, based on this, I think.
Any other thoughts?
btw - you guys are GREAT! my 1st time in this forum, and the response was quick and very helpful. I like this place alot!!!

 

[jbpsrc763]

diagram for above post

 

[flyingron]

Your testing methodology is wrong. You should never put a meter on 3 and either 4 or 5. However your meter's probably high enough impedance to not trip the GFCI, but I'd measure between 4&5 and each of 4 and 5 compared to the unnumbered screw above the one labeled 5 (that's the load neutral). But you're right, the GFCI is probably shot. Runs about $100.

 

[C'est Moi]

I agree gfci is shot. What flyingron was saying when you test the breaker use the neutral at the breaker not on the bar. In this case it won't make a difference, IMO since you had 118 on one leg.