Italian water heater not working - pilot won't stay lit

[bushmlev]

Please help me! I'm in the USAF, stationed in Italy, and my water heater is acting up. I've gone to the landlord a few times about the problem, but a person that has no idea how to fix it keeps coming out, and I'm getting sick of cold showers!

I've done as much troubleshooting as I can do, but I really don't know all that much about how these things work.

Long story short, it's a gas water heater and the pilot won't stay lit. What I've learned about it is that if I disconnect the air intake pipe about 4 feet from the heater, the pilot comes on immediately, and will work until I "normal it up" again. What is funny about this is that the air intake pipe is only about 8 feet long, and I can see through it; it's clean as a whistle. I thought that the problem could still be a plugged exhaust pipe, so we had someone "sweep" the exhaust pipe... still no joy.

Any suggestions? I need someone that actually has a clue to help me, because I don't know much and neither do the techs I've dealt with recently... Thanks for any help in advance!

 

[LiQuId]

Could be A dirty orrifice. that you checked the Venting and make up air is a good start as that is often the problem.

is it a high efficiant appliance? What I mean is do you have to light the pilot by hand ? you say it " comes on immediatelly " which is why I ask.

IF its a high efficiant appliance then youre problem could be a blocked pressure switch.. look for a small tube that connects to the vent pipe, basically this pipe connects to a switch that srnses the negative pressure created by the draft crated when the burner fires, NO activation of this switch could cause the pilot, burner or both to extinguish, It MAY also explain why it would stay lit when you blocked off a intake opening as you would have crated more pressure in the area of the appliance... check it out and ifyou have a tube then disconnect it and clean it out with a compressed air cannister.

hope this helps... We're a pretty helpfull bunch on here ( plumbers and gasfitters ) others will offer suggestions as well..


I HATE COLD SHOWERS ...

 

[havasu]

I'm thinking you need a thermocoupler.

The thermocouple is the pilot's, well, co-pilot! It is the electronic device that senses if the pilot flame is hot enough to ignite natural gas or propane fuel to the burner. If the thermocouple thinks it's safe, then it keeps open the main gas valve located in the pilot assembly. If the thermocouple does not sense enough heat from the pilot flame (such as when the pilot is out), then the thermocouple shuts off the gas valve to the burners.

How the Thermocouple Works

So what is this thing and how does it work? Well the thermocouple (technically called a thermocouple junction) is a device that contains two metal wires welded at the ends and placed inside a protective metal case. The thermocouple sensor is found at the business end of the pilot flame and is designed to be placed in the hottest part of the flame. The other end is connected to the pilot valve body. As the thermocouple heats up, it produces a small amount of electricity and when it gets hot enough from the pilot, send a signal to open the gas valve by using a solenoid operated by a 24 volt transformer. The thermocouple calls the shots, and by converting heat to an electrical signal, it allows the gas valve to open or close.

Once the gas valve is open, gas is then constantly supplied to the pilot and as required for the gas burners (as called for by the thermostat). If the pilot goes out, then the thermocouple gets cold and produces no electric signal to open the gas valve's solenoid and the gas valve shuts off the gas supply to the pilot and burners.

 

[bushmlev]

Thank you both! I'm looking into the thermocouple thing as we speak!