Electric head - propane solenoid interference

[OrioninHawaii]

Okay this is a weird problem - I liveaboard a 48 ft 1986 celestial ketch.
Well maintained.
The heads are all electric flush (12 V) the forward on has a holding tank and the aft head has a lectrasan.
We have a force 10 propane stove with a trident gas control panel.
Whenever the stove is on and either toilet is flushed it flips the solenoid and shuts the stove off.
I have had two electricians check it out while working on other jobs and they cant find a thing. They are supposedly on separate circuits.
It's not life threatening. Only irking. I have almost decided to attribute it to galley ghosts.
Could it be frequency interference?
Anyone have a clue?

[christyleigh]

My Guess would be that the power spike from the flush is momentarily dropping the voltage low enough to fool the solenoid.

[OrioninHawaii]

Nope - my electrician checked that one out...That was the first guess...

[Melrna]

Short of the Hawaiian gods having fun at your expense, I would make sure they are on two separate circuits. I would pull down the circuit breaker panel to make sure none of the wires are not on the same post, crossed onto a common hot bus bar, wired in series somehow or ground wire not shorting out somehow.
I would take voltage readings across the propane circuits while someone flushes the toilet. If you lose voltage than there is a short/cross wire somewhere. The fun begins if they are. I would than start tracing out wires for both systems to see where they are crossed. I would start tracing out the propane trident gas control panel first. You will need a voltage meter to help find this. First thing I would check on the panel is the wires - corrision, tight, connections.

[OrioninHawaii]

Yep Melrna. That's all been checked- it's on separate circuits and the electrician checked the voltage during the flush- Everyone who has been involved with this has said those same things and when they've checked it out find nada...
Someone mentioned something about frequency interference and I thought I'd see if someone knows about that possibility-

[SVAuspicious]

Originally Posted by OrioninHawaii

Someone mentioned something about frequency interference and I thought I'd see if someone knows about that possibility-

Perhaps they meant radio frequency interference (RFI). Conceivably the electric motor in the head is generating a signal that is getting into the propane switch and causing it to flip off. This is less likely if the motor has a metal case; if it is metal try grounding the case.

You might also try shielding the propane switch. Before you put a lot of effort into a nice permanent shield, pull the switch off the bulkhead and put it inside a grounded metal box (you can bend something up from any kind of metal mesh).

[OrioninHawaii]

THanks auspicious- I will try that and see what happens...

[donradclife]

My propane sensor got funky after it was about 10 years old, and would shut off at wierd times. Replaced it with a new unit and all the problems went away.

[wind_magic]

If you really think it's RFI you could put a snap on ferrite core near the propane controller on it's power lines and see if that helps, only cost you about 6$us at radio shack to find out, and if it doesn't work you can use the core for something else that is receiving interference from your radios when you transmit.

Because of all of the radio equipment I have it is standard practice on my boat to protect every device's power with ferrite beads and I do the same thing for most signal lines, especially if they run any significant distance. This not only helps to keep the device from receiving RFI but it also helps keep it from transmitting RFI using it's own power cable as an antenna.



Link: What are the "bumps" at the end of computer cables ?

[lynger1]

Originally Posted by OrioninHawaii

Okay this is a weird problem - I liveaboard a 48 ft 1986 celestial ketch.
Well maintained.
The heads are all electric flush (12 V) the forward on has a holding tank and the aft head has a lectrasan.
We have a force 10 propane stove with a trident gas control panel.
Whenever the stove is on and either toilet is flushed it flips the solenoid and shuts the stove off.
I have had two electricians check it out while working on other jobs and they cant find a thing. They are supposedly on separate circuits.
It's not life threatening. Only irking. I have almost decided to attribute it to galley ghosts.
Could it be frequency interference?
Anyone have a clue?

Hi disconect stove 12vdc supply and negative
run temp wire positive and nagative from isolated batt and try again
if this wil fix your problem then
1- you have back feed trough negative
2- 12Vdc solenoid fluxulation max off 10% if this is higher or lower solenoid will rattle or change status
3 measure voltage to solenoit when you flush 10% variation will rattle solenoid

Good luck let me know
Lynger