My water heater is part of our central heating(Gas).After having been on for about 20-30mins it rumbles,bubbles and bangs quite loudly before pouring water out of the overflow.Needless to say I'm concerned that sooner or later something is going to seriously blow,not to mention the fact that its not producing large amounts of hot water as this is being thrown out.
Can you help me please?

Hey Stormin99:

Have you ever power flushed your water heater..

Here, you want to leave the water supply on full to the heater, hook a hose onto the drain at the water heater and then open the drain all the way...

If you drain into a bucket in the back yard to start, you will most likely see a serious build up of sediment (minerals, anode rod sediment, etc... ), debris, etc.

You want to power flush for 5-10 minutes... I turn the cold water on and off a couple times when flushing... just real quick bursts... aids in blasting at stubborn sediment.

How does this all work to reduce the bubbling/noises, etc..? Basically, there is a sediment layer that has built up and has become so thick that when the water is heated it boils UNDER the sediment and causes this eruption/bubbling effect you are speaking of.

There is a DIP TUBE in the cold water supply that directs the cold water to the bottom of the heater... it is this dip tube that forces water to be directed at the sediment during flushing that helps to loosen it.

Be aware that after a power flush you want to open a hot water faucet at a laundry tub or at a tub spout first... so don't clog any aerators.

You may also need to CAP the drain after flushing as sediment can get caught in between washer and seat at the drain (purchase a boiler drain cap).

Also, I would love to know what temperature the hot water in your house is.....may be that there is another issue here...or may also be that your relief valve is defective (the "overflow" thingy... ;) )

Once power flushed you want to do this every month or two from now on... will increase the life of your water heater!

If you get this fixed... come on back and talk to me about ANODE RODS... :) More to know about water heaters!

Also note that the dip tube in the picture below should be in the cold water inlet to the heater... just so you know!

Let me know what you think... MARK

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