Re: cold showers
Posted by Philip on September 04, 2002 at 14:20:50:
In response to Re: cold showers
If your flow rate is 5 gal/min and you have a 40 gallon tank you will use up all the hot water in 8 minutes assuming you are not mixing in any cold water. Since in the beginning of your shower you are mixing in cold water, the hot water will last longer than 8 minutes. I am not surprised that you are running out of hot water. You are using the water faster than it can be heated.

The water system is a closed system. For every gallon of hot water used, one gallon of cold water enter the heater. Regardless of how the water enters the tank the water will get colder the longer the water is used.

You have several solutions. 1) Buy a shower head with a flow limiter that limits the flow to 2.5 gallons per minute. You might need to try several before you find one you like. This should allow a 15-20 minute shower. 2) Reduce the flow rate using the facuet. 3) Raise the hot water heater temperature. Be careful to stay below 120 to avoid scaling hazard. 4) Buy a bigger water heater. 5) Buy a tankless heater which heats the water on demand and can deliver a endless supply of hot water.

: I have all new plumbing in my home. A new hans grohe showerbar set, a new june of 2002 bradford white 40 gal natural gas hot water heater, 100lbs of pressure coming into my house. The shower head is delivering 5gals/min of mixed, warm, water. 5gals/min is what is expected with this amt. of pressure according to literature supplied with the head. A few minutes after starting my shower, the water begins to cool. I turn it up to a hotter setting several times throughout the shower. After 10 minutes, I have the temp control maxxed and the water is getting cold. Plumbers have changed the heater and the mixer valve. Once the water gets cold the heater makes a hissing noise which I have been told is proof that I am emptying the heater as I am hearing condensation from the inside of the tank dripping down. If this is true, then the heater must not be working properly. A video of how the new injector style dip tube works at the bradford white website, illustrates how the tank is filled with new water before it can empty. Do you think the valve which allows water to enter the heater possibly operates or is somehow dependant on pressure. Is it possible that the extreme pressure coming into my house is causing the fill valve on the heater to malfunction until the tank is empty. Regardless of the temp which the heater is set at it always runs out in 10, gradually getting colder even when there is still some hotter water left. Less of the hot is coming in. It has to be either a case of 2 heaters, both with bad dip tubes or pressure problems even though B.W. states the heater will operate at a much higher pressure than I have.

Replies to this post