hot water heater question

[raaizin]

I just purchased a new hot water heater and have a question. There is an LED on the front which blinks every 3 sec to show unit is operating properly. Also there are a couple of wires coming from the control unit. There isn't a power source going to the unit. Is there a battery in there, does it need servicing. The only reference I see is a tag which states the water heater uses the pilot light to power an electronic gas valve and needs no external source of electricity.

This is the unit I have, the manual can be viewed on this site.
http://www.pexsupply.com/AO-Smith-GCVL-4...ter-Short-Model

 

[simple_gifts]

Where is the installation manual?

 

[spasm3]

The led is probably powered by the thermocouple when the pilot is lit or whenever gas is being burned.

 

[fsskier]

Water heaters, old style furnaces, other appliances with a pilot light use a thermocouple that is visible in the pilot light "flame envelope". It uses the heat and carefully bonded dissimilar metals (google thermocouple and an explanation will jump out at you) to generate a continuous small voltage and current. This is used to hold the gas valve open....the reason you have to hold the gas valve down for 30 seconds or more after lighting the pilot light in order to make it stay on.

If the pilot light fails, blows out, whatever, then the gas valve soon shuts off and stops the flow of gas. This is the reason that you are still alive, and have not been blown up when a pilot light blew out sometime and filled your house with gas!!

This thermocouple can easily also supply an LED.

 

[Mik]

well, as George Carlin so cleverly pointed out, hot water doesn't have to be heated, so you likely bought a cold water heater

 

[simple_gifts]

Originally Posted By: simple_gifts
Where is the installation manual?


Here it is

http://www.hotwater.com/lit/im/res_gas/186487-001.pdf

 

[raaizin]

Originally Posted By: fsskier
Water heaters, old style furnaces, other appliances with a pilot light use a thermocouple that is visible in the pilot light "flame envelope". It uses the heat and carefully bonded dissimilar metals (google thermocouple and an explanation will jump out at you) to generate a continuous small voltage and current. This is used to hold the gas valve open....the reason you have to hold the gas valve down for 30 seconds or more after lighting the pilot light in order to make it stay on.

If the pilot light fails, blows out, whatever, then the gas valve soon shuts off and stops the flow of gas. This is the reason that you are still alive, and have not been blown up when a pilot light blew out sometime and filled your house with gas!!

This thermocouple can easily also supply an LED.



That would explain how the hot water heater worked when we lost power for the week. Thanks for solving one of lifes little mysteries!!

 

[doitmyself]

If you open up the OP's link and click on "Brochure", it states this:

"Our new high-tech gas control is a self-powered gas valve that uses a thermopile to generate the power needed to operate the control. No external power source is required." (what fsskier said!)

A quick glance at the owner's manual and I did not see this mentioned.

 

[raaizin]

Originally Posted By: doitmyself
If you open up the OP's link and click on "Brochure", it states this:

"Our new high-tech gas control is a self-powered gas valve that uses a thermopile to generate the power needed to operate the control. No external power source is required."

A quick glance at the owner's manual and I did not see this mentioned.


It was on a tag on the side of the unit, sorry I didnt state that

 

[Rick in PA]

Just a little insight on how the circuit may work. We had something similar to detect a low energy source on one of our products years ago. The low energy source, in your case a thermocouple, could be connected to a circuit containing a capacitor. The capacitor would store the energy over time, in your case a few seconds. When enough energy is stored in the capacitor, the circuit "fires" and discharges the capacitor through the LED causing it to flicker.

Just flashing an LED as opposed to continuously illuminating it can save considerable energy. This is why sometimes you see an LED flicker to indicate operation in battery powered devices, for example a smoke detector. It greatly extends battery life.

 

[JTK]

Ughh...

It didn't take them long to make sealed burner gas water heaters even more sealed and complicated. Now you have to rely on an LED to verify the thing is lit?!?

raaizn, just make sure you keep the intake screen under the unit clean of fuzz/dirt.

 

[Wolf359]

I like how they don't mention that if you replace the anode rod every few years, it will prevent the tank from rusting out and having to buy a new tank every 6-9 years. There's a few articles about it if you google anode rod replacement.