Low hot water after using fresh water tank

[Paul GA]

We had to use freshwater tank two nights ago because of freezing temps at the campground. Since then we run out of hot water sooner than usual. We are back on shore water now. 6 gal electric and gas. We use both when showering. Gas working, using usual showering regimens on of on off so the only thing that changed is we were on the pump overnight.

[Flybob]

The water source should not effect how long the hot water lasts. What you may be seeing is the variation in the temp of the cold water going into the system. Normally city water is about 50F as it is supplied underground. If you are using the FW tank due to freezing temps, it is possible the water going into the system is closer to 35F This means that not only do you have to add more heat, but any mixing of hot and cold will result in cooler water.

[Paul GA]

Temps are back up, actually warmer than first night when we were on the hose. Plus using heated hose? I mentioned tank maybe air in the heater but just cracked pressure relief and water came out.

[nomad297]

The temperature of the water in your tank may have been colder than that of the water coming from your hookup. This colder water takes longer to heat and as it enters your water heater, mixes with the hot water and makes it cooler than it would be otherwise.

Bruce

Edit: I just reread your post. Just reverse my theory for your situation.

Bruce

[yworrydog]

Your pump likely puts out more water the you hose hook up if you use a regulator. Perhaps you just use more water that way.

[Paul GA]

Never used the shower on the tank