Water Heaters - running noise and Increase in gas bill

Hey

I have a Maytag Series Eight 50 Gal gas water heater that is about 8ish years old. It sounds as if the cold water is continuously running very slowly into the tank. When I shut off the cold water valve the noise stops. I recently drained it hoping to remedy the problem but the noise is still there. Our gas bill also jumped up by 20 therms despite us not using the furnace this last month. I think it is due to the water heater running almost constantly. What is wrong, and how can I fix it?

Thanks

Having the water flowing constantly would indicate there is a leak or open valve somewhere. Where does your Temperature and Pressure valve exit? Sometimes they go below the floor, and sometimes they are vented to the exterior of the house (preferred) If it is bad, you will see a flow of water out the pipe. One more thought, do you have a recirculating pump on the water heater, or at the furthest faucet? If so, the pump is sending hot water to the extremities of the house to keep you supplied with hot water at all times. Sometimes they are good, and sometimes they are inefficient.

To add to what chandler has replied,

The relief valve could only be leaking occasionally after taking a shower or something. This could be caused by thermal expansion. Also, if the relief valve is leaking very little, I have seen it turn to steam before hitting the ground, so touch the blow off tube about 12" down and see if it is hot. It can feel warm next to the relief valve but as you get further away it should get cooler. If not then the relief valve is slowly leaking by.

One common item overlooked by most people is the simplest. Are there ANY faucets dripping hot water ANYPLACE in the house?

Kitchen, lav (bathroom), shower or tub/shower, Washing machine valves. Or anything else you have that may use hot water.
Also check the floor around the water heater for moisture. It could be a small leak that is not enough to puddle up. Possible water heater leaking.


WOW, I almost forgot you said it was a gas water heater !

IT IS VERY POSSIBLE that the water heater is leaking in the flue passageway of the water heater. If it is a small leak it will drip into the bottom of the water heater and every time the heater fires up it will evaporate any water, so it will not be noticeable.

Check all other possibilities first.

thanks,

The valve drains into the washing machine drain pipe next to it. There is no water coming out of it. I don't think we have a recirculation system but i would have to get under the house and check.

We just got the water bill today and it more than doubled. There is a leak somewhere just have to find it.

Thanks for the help