Mazzei Flash Reactor Causing FL1 on my Sundance?

[tex912]

Hi everyone. Im new here but have owned my 2003 Sweetwater (sundance) Palermo hot tub since new and have always done my own repairs but am completely at a loss here.
   Started out with a --- displayed which is Watchdog system activated due to overheat. So I replaced the temp sensor and all was ok for about 10 min until I got a FL1. I know...get the air bubbles out, check the flow switch. Did both. The circ pump and jet pumps and light works fine until I call for heat. After the heater warms up a bit, it shuts down and nothing works except the temp up/down buttons and I get an fl1 code. After letting it cool off a while it works again only to do the same thing. I went thru many test including removing the high limit sensor from the steel tube to see if that was what it was but to no avail. I did find however that if I lowered the temp control lower than the water temp the circ pump would continue runing and all jets and lights would also work, but as soon as I call for heat the fl1 comes up and everything shuts down again.

    I then bypassed the Mazzei Flash Reactor thinking it was an inline filter and possibly clogged. This seemed to work for about 5 hours. The tub heated up no problem from 91 reaching 104 and continued to work. I thought maybe the flash reactor was slowing the flow and overheating the heater. Is this even possible? 

     It ran for 5hrs before acting up again. I got the --- on the display and the tub was not working. I shut down the breaker and reset the tub. It gave me an fl1 code but I was able to turn on the jets and everything is fine now. Could this be a larger problem such as a bad heater or circuit board? Also, do I need to replace that flash reactor.

Things I have already done...

New filter
New temp sensor
removed Flash Reactor
checked flow switch
Replaced flow switch last year
Replaced circ pump last year
Checked with hi limit off pipe.

[clover]

"Flashing Flo" or "Solid Flo", are two differrnt signals to the circuit board.  You should be able to see the flow of water actually close and the magnetic finger switch, when it dosen't close completly = "Flashing Flo", when it does NOT open it signals that to the circuit board = "Solid Flo" and nothing works.

As for 2 temp sensors, they should agree within a few degrees of each other, IF NOT = watchdog, or (----) on the read out panel and nothing works.  A test plug would be real handy here.

When you get the "Flo" message, verify the circ pump is actually moving water through the flow switch.  I have witnessed flow switches that appear to OPEN but the circuit board says something different and it remains a secret until you check continuity between the two wire leads.  This is what the switch is telling the circuit board and may not be seen by the eye. 

When you have the problem, power the system down, remove the sensor loom from the circuit board, (it may not be open to the circuit board) and then put it back on and power up the spa.  This will duplicate an opening of the switch and it will close when the circ pump starts up reverting to normal operation until shut down again. 

Could be a bad flow switch or a failing circ pump, put your hand on the body of the circ pump and see if it is "very hot" to the touch.

[tex912]

Thank you for replying. This has been a nightmare. The flo1 code I get is always flashing between fl1 and the current temp. Sometimes the tub in completely shut down and sometimes I can turn on the jets.

  I just went out and the circ pump is running and tub is operational. I disconnected the flow switch and the circ pump continued to run. I tested the flow switch unplugged?..and w/my meter at 20k it read 16.88? Not sure if im doing it right. started at 200 on meter and it read 1. moved to 2000 and it read 1. moved to 20K and it read 16.88 and the water was flowing, I also checked with the tub off and no flow and the reading was the same.

As for the circ pump, I could put my hand on it firmly and indefinately. It was warm but not uncomfortable to the touch.

My two temp sensors are.. one in the tub by the filter in the water and the other is touching the stainless pipe coming out of the heater. I don't think they can be the same temp.Not sure if this is what you meant.

I also removed the new filter and put the old one back on since it seemed like the new one always had air bubbles trapped in it. (Wouldn't it be nice if thats what is was).

Current temp is 100 and i set temp to 103 to see if it shuts off again. Ill let you know.

[tex912]

Tub heated up to 103 w/no problems so I turned the temp down to 100 to let it cool and noticed the circ pump goes off when I do this. The tub temp cooled off to 100 and I bumped it back up to 103. It is currenlty 102 and rising and still no problems.  Ill let you know.
  In the mean time if someone could explain the flow switch test to me and if I did it correctly I would appreciate it. Not sure what they mean by continuity. Just need to have the same number with out it changing? I thought there was something about it reading 0 when I test it? Sorry. Not real good electricly, more mechanical.