Air in hot water pipes

[John Vee]

Replaced our electric hot water heater at the end of last year and have air in the hoy water lines ever since. Air is only in hot water lines, never in the cold water lines. I have tried (twice) turning on all hot water faucets and appliances that use hot water and let the water run for a full 15 minutes but the air comes back in a day or two. I have city water, not a well. Any advice on how to get rid of this problem will be greatly appreciated!

 

[Terry]

Are you sure the themostat isn't too high?
There is no way for air to get in the line, but it is possible for the water to be too hot.
What is the temperature at the faucets?

 

[Sponsor]

 

[John Vee]

Are you sure the themostat isn't too high?
There is no way for air to get in the line, but it is possible for the water to be too hot.
What is the temperature at the faucets?

The temperature is set at 115 degrees at the water heater. The water at the faucets does not feel overly hot.

 

[Jadnashua]

IMHO, I prefer a hotter setting and the use of a tempering valve (they're required where I live) to keep the temperature safe. This helps to ensure nothing can grow in the hot water.

But, the sacrificial anode can cause some outgassing depending on your water chemistry. Does the 'air' have any unique smell? Swapping the anode with a different material may stop it if that's it.

Are you on a well, or public utility? Do you have a hot water recirculation system?

 

[John Vee]

IMHO, I prefer a hotter setting and the use of a tempering valve (they're required where I live) to keep the temperature safe. This helps to ensure nothing can grow in the hot water.

But, the sacrificial anode can cause some outgassing depending on your water chemistry. Does the 'air' have any unique smell? Swapping the anode with a different material may stop it if that's it.

Are you on a well, or public utility? Do you have a hot water recirculation system?

I am on a public utility and do not have a water recirculating system. I do not smell any odor in the air. This water heater is fairly new (November of 2014). It is a Whirlpool model with a 12 year warranty. Would you know of any issues with the anode rod material on these electric heaters?

 

[Jadnashua]

MOst manufacturers use the same type of anode material, so it would not be unique to a single brand. YOu might make a call to the building inspector or the water utility and ask them if a different anode material would help, or talk to a plumbing supply house to see what they are selling. Course, that might not be the problem. Having it restricted to the hot water, though, is strong evidence that it is a chemical reaction, and the only thing designed to react in the WH is the anode, which, with most water, isn't an issue.

Swapping an anode is fairly easy IF you can get the original one loosened. If you have height clearance issues, you can buy them with segments, designed to bend so you don't have a rigid rod that needs to go nearly straight up which is what the OEM one would be as installed at the factory.