UPDATE
UPDATE
First thing I would check based on what has been said so far is to make sure heater is denergized if there is no proof of flow. This can be checked with or without water.
Excellent point, kwired.
I wasn't even thinking of where to start troubleshooting, just to do one's own investigating as opposed to relying on the customers "observations".
The part in red above: The pastor told me the light had to be off for it to be on.:happyno:
Just opposite of that. Good thing he is not the one that takes care of it.
Ok, here's an update on the baptistry. Here's the setup, or how I see it anyway.
Heater is powered from a 30A GFCI breaker, then to a 30A disconnect
To a flow switch for the heater than to the control box
Pump is powered from a 120V GFCI receptacle to the control box
The heater will not operate unless there is flow, and I checked that first. NO switch was not closed, but the heater was tripped and had been off for several days.
In the control box there is a thermostat on one side and what I guess is a high limit switch on the other side. At the high limit switch is where the reset button is for the heater.
There's not much auto control over this system other than the thermostat and flow switch. You have to manually fill/drain the tub.
I took the limit switch out of the box and checked it best I could and didn't see anything wrong with it. I was wondering if the springs and pressure plate that trips the limit switch could be going bad and not letting it stay compressed enough to keep the heater from tripping. I ran the thing for a couple of hours after I put it back together and it didn't trip. They tell me that it trips as soon as they turn the breaker on. They reset it and it trips again within a few minutes.
I also told them they that there was no need of having to go downstairs to turn the breakers on/off since they could use the thermostat to control the pump and if the pump's not on the heater won't operate.
Hope I've explained this well enough. If not I'll try to answer any questions you might have.