Burner Stays On, Water Turns Warm

[richard blaine]

Hi, I have a 50 Gallon Ruud Achiever - Professional, gas with conventional thermostat, just over 1 year old, purchased by the previous homeowner. I only use the hot water once per day for a bath or shower. When I turn on the hot water, the pilot fires the burner and the water is hot. After a few minutes, the water gets colder: it goes from hot to warm, while the burner is still on. Then I shut off the hot water, and the burner stays on for at least 10 minutes. After about 30 minutes, I run the bath again, the burner fires and the water stays hot. It seems the tank runs out of residual hot water and does not heat up the incoming cold water fast enough. The plumber checked the dip tube (which is fine) and said the water should be consistently hot as long as the burner has fired and remains on.

 

[Fitter30]

With just the water heater burning in the whole house can clock the gas meter. This will tell how btu's its using to compare it with the name plate.

How to Clock a Gas Meter — HVAC Tech Hangout

hvactechhangout.com

 

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[richard blaine]

Hi, I have a 50 Gallon Ruud Achiever - Professional, gas with conventional thermostat, just over 1 year old, purchased by the previous homeowner. I only use the hot water once per day for a bath or shower. When I turn on the hot water, the pilot fires the burner and the water is hot. After a few minutes, the water gets colder: it goes from hot to warm, while the burner is still on. Then I shut off the hot water, and the burner stays on for at least 10 minutes. After about 30 minutes, I run the bath again, the burner fires and the water stays hot. It seems the tank runs out of residual hot water and does not heat up the incoming cold water fast enough. The plumber checked the dip tube (which is fine) and said the water should be consistently hot as long as the burner has fired and remains on.

Should the water heater "cycle on" when the temperature drops below a certain level, even when there is no call for hot water? If that's the case, then the temperature sensor isn't working correctly. The burner only lights when I use the hot water.

 

[Fitter30]

Burner can come at any time that the probe sees a drop in temp can be from standby loss. 15-25° differential is common. Have you clocked the gas meter?

 

[richard blaine]

Burner can come at any time that the probe sees a drop in temp can be from standby loss. 15-25° differential is common. Have you clocked the gas meter?

Burner can come at any time that the probe sees a drop in temp can be from standby loss. 15-25° differential is common. Have you clocked the gas meter?

Apparently the burner does not come on when the temp drops, or it comes on too infrequently to have enough residual hot water. The burner only lights when I use hot water -- then it stays on for about 15 minutes after the water has stopped. The plumber said it will eventually stop lighting.

 

[Fitter30]

Apparently the burner does not come on when the temp drops, or it comes on too infrequently to have enough residual hot water. The burner only lights when I use hot water -- then it stays on for about 15 minutes after the water has stopped. The plumber said it will eventually stop lighting.

New gas valve is needed. Call Rudd maybe they do something for you.

 

[WorthFlorida]

Why are you bothering with the gas WH. It's not dissigned for cycling Using the gas valve. A pilot uses very little gas. You need to look up the recovery rate. Heating 40-50 gallons of cold water takes a while.
Electric WH is what you want

 

[GReynolds929]

Why are you bothering with the gas WH. It's not dissigned for cycling Using the gas valve. A pilot uses very little gas. You need to look up the recovery rate. Heating 40-50 gallons of cold water takes a while.
Electric WH is what you want

You're comment is hard to understand. Gas water heaters are designed to cycle as needed. Electric does the same and takes longer to heat the water in general.

 

[WorthFlorida]

You're comment is hard to understand. Gas water heaters are designed to cycle as needed. Electric does the same and takes longer to heat the water in general.

Adjusting the thermostat everyday, no. You’re not saving much since you need to reheat the same water and dealing with temperature swings. Leave it at the normal temperature, around 120 degrees. Unless you are out of the home for several days, then you’ll be saving some. New WHs are very efficient since the energy act of 2010.