solenoid valve replacement

[oregon18]

I have just finished replacing the solenoid valve on a Xintex s-2a propane detector. All went well, but the valve is very hot to the touch. There was no indication of which wire was pos/neg, so I thought it made no difference. It makes me nervous to have such a hot valve with propane running thru it--Does anyone have knowledge of this situation??--thanks


Jim Elder
ericson 35-3
Olympia,Wa

 

[Flight Risk]

Jim,

Check the voltage at the solenoid then at the switch and last at the battery. You should see ZERO voltage drop if your electrics are in good shape and wire is right size. A drop of .1 or.2 volts is probably ok at the solenoid as compared to battery voltage.

FYI your battery voltage should be about 12.6 at rest. Lower than this could indicate a battery that needs to be charged or replaced. Does the coil seem warm in the morning, at anchor when you make coffee? Weak or discharged battery could be the root issue.....

I am suspecting you may have poor connections in the wiring to the solenoid, perhaps on the other end at the switch. The wire itself may be going south, if it has turned black or green inside the plastic jacket. Strip back a few inches and see what condition the wire is in.

Low voltage will increase current flow which makes heat. More heat makes more resistance, and so on and so on......Either way, excess heat is a short route to early failure.

Coils will sometimes be a little warm when energized but not hot. You may also have a new defective one. Check to make sure the coil is rated for 12VDC and that it is a not mis-labled AC coil. Also compare the current draw with the old coil. It may be the new one draws more current, hence the wire in your boat may be a little small, causing high current draw from high resistance...

Chris
E 34 Flight Risk

 

[rwthomas1]

FWIW, the solenoid in my Xintex system runs pretty hot as well. Always has. There used to be a large latching relay (unrelated) on the boat as well and this too was pretty hot after extended use. I bench tested that one and it appears this is normal, for that solenoid anyway. They get hot, but not enough to burn you, uncomfortable to touch for long periods would be good way to put it. I never worried about it, I know the propane solenoid is the correct part..... RT

 

[Tom Metzger]

Low voltage will increase current flow which makes heat. More heat makes more resistance, and so on and so on......Either way, excess heat is a short route to early failure.

I'm in Florida now so I'm not sure of the laws here, but in NY & Washington ohm's law is still valid for DC circuits and the current drops with the voltage.

Current(I) = voltage(E) divided by the resistance(R). I=E/R Therefore, lower voltage, lower current. As the coil temperature increases the resistance goes up and the current drops.

With AC solenoids the coil can overheat if the voltage isn't high enough to fully pull in the armature, but this is not what we deal with on our boats.

 

[oregon18]

Thanks all for the replys--think I will just keep an eye on it for now-seems to be working properly--Jim