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las vegas
Sep 29, 2009, 06:18 PM
What is the function of the diode in a gas hotwatwer heater and should it be replaced every two year
las vegas

KISS
Sep 29, 2009, 06:29 PM
Only thing I can think of is that a flame rectifies and this is how to tell if there is a pilot so that the main gas valve can open.

Otherwise, clueless.

letmetellu
Sep 29, 2009, 07:22 PM
I am not questioning your knowledge of water heaters but could you be talking about an anode rod that goes into the water heater tank.

If so they do deterioate over time and it would not hurt to check it to see if it is almost gone.

If this is not the object of your question I apologize for my stupidity.

ballengerb1
Sep 29, 2009, 08:08 PM
Letme isn't stupid, I think the poster just used or heard the wrong word. Heater have an anode , a stink rod, a sacrificial rod which protects the tank's lining from your LV water.

letmetellu
Sep 30, 2009, 10:16 AM
The only other thing that I can think of where the poster would have used the word "diode" is that some of the anti-explosion water heaters have a safety cut off built into the thermocouple line that is in the heating chamber and if the flames starts to roll and over heats the heating area it will snap the protector off. This requires that the thermocouple be replaced and the problem that caused the overheating to be repaired.

las vegas
Sep 30, 2009, 10:40 AM
I am not questioning your knowledge of water heaters but could you be talking about an anode rod that goes into the water heater tank.

If so they do deterioate over time and it would not hurt to check it to see if it is almost gone.

If this is not the object of your question I apologize for my stupidity.

Thank you,however can you tell me the function of the anoid. Lasvegas

KISS
Sep 30, 2009, 11:26 AM
Water contains ions (Say sodium and clorine from salt) for instance.
When yiou combine ions with dissimilar metals you get a battery. When you get a battery, you have corrosion.

An example is salt used on the roads in the winter time combined with water create rust if not washed off.

You can take a lemon and insert two disimilar metals in it and come up with a voltage or a small battery.

There are all sorts of disimilar metals in a water system, for instance solder and copper. This has the potential of creating a small battery.

By carefully selecting the material, usually magnesium, you can "tell" a system to preferentially corrode this. It's kind of like the path of least resistance.

The anode is just a hunk of magnesium, sometimes other metals, that hangs in your tank. This rod corroods first, thus preventing holes in other parts of your water system. The ions are used up in the conversion.

Chlorine ions might be sucked up by the magnesium to form Magnesium Chloride instead of, for instance, copper chloride thi preventing damage to copper plumbing.

ballengerb1
Sep 30, 2009, 02:04 PM
Short answer, something has to corrode and the anode is there to be the first and only thing to corrode rather than the tank. The anode is cheap and easy to replace so we call it sacrificial.

letmetellu
Sep 30, 2009, 06:12 PM
Water contains ions (Say sodium and clorine from salt) for instance.
When yiou combine ions with dissimilar metals you get a battery. When you get a battery, you have corrosion.

An example is salt used on the roads in the winter time combined with water create rust if not washed off.

You can take a lemon and insert two disimilar metals in it and come up with a voltage or a small battery.

There are all sorts of disimilar metals in a water system, for instance solder and copper. This has the potential of creating a small battery.

By carefully selecting the material, usually magnesium, you can "tell" a system to preferentially corrode this. It's kind of like the path of least resistance.

The anode is just a hunk of magnesium, sometimes other metals, that hangs in your tank. This rod corroods first, thus preventing holes in other parts of your water system. The ions are used up in the conversion.

Chlorine ions might be sucked up by the magnesium to form Magnesium Chloride instead of, for instance, copper chloride thi preventing damage to copper plumbing.***************************************** ********************************

I could not have said it any better myself, if fact I could not have said it near as well. Very good job "Keep it Simple

speedball1
Oct 1, 2009, 05:07 AM
And here's what they're talking about. (see image)