Improperly Installed Water Heater Causes Elusive and Annoying Problems
A residential storage-type water heater probably requires less attention than any other home appliance. It sits silently providing hot water (in most cases) on demand 24 hours a day. Problems are usually few and far between. But I know from experience that when a problem occurs, it can be elusive, annoying, and nearly drive you mad trying to figure out a solution.
The water heater in question was under a warranty, but the warranty was only against a leaking tank. Since it had been first installed we had experienced an erratic hot-water supply. It was one of the early, so-called energy-efficient water heaters, and, as such, I knew the rate at which the tank reheated the water would be slower than the old tank. In addition, the tank was smaller than the old one, again for the sake of energy conservation.
On those occasions when we would run low on hot water, I would alternately blame it on the fact that we had an early version of the energy-efficient models and the bugs weren't all ironed out. Or I would blame it on the fact that I had used the dishwasher or washing machine or that someone had just taken a shower.
In addition to an erratic hot-water supply, I was also using more gas in the summer than I was before I had the new tank installed, a problem that I was at a loss to explain, since this was supposed to be an energy saver.
Finally, one morning I was the first one up (a rare occasion) and my bath was barely warm. I knew I either needed to replace this water heater, or I had to find out what was causing the problem. There is nothing quite like a cold bath to rouse a person to action.
With a deep fat thermometer, I began to take water temperature readings, something I should have done much sooner than I did.
I found if no one had used any water for awhile, the temperature would be 140 degrees, but one cycle of the dishwasher and the temperature would drop to 115 degrees. This suggested that the hot water was being diluted in some way.
When the tank was first installed, I found that the supply pipes attached to the top of the water heater did not match the hot and cold labels on the tank cover.
When I called the plumbing shop about this, I was assured the tank was installed properly, and because my household water supply lines above the water heater were reversed, the plumbers claimed they had to move the dip tube to the hot water side. Not being able to see inside the tank, I foolishly believed them.
When you examine the top of a water heater there are two pipe connections marked "hot" and "cold". If you could see inside the tank, you should find a long tube running from the cold water connection to just above the bottom of the tank.
When hot water is used, it is drawn off the top of the tank; as cold water enters the tank to replace the hot water, it is delivered to the bottom of the tank through the dip tube. But if the dip tube drops off, which will happen, the cold water enters the tank at the top and immediately mixes with the hot water being drawn off the top.
In this case, you can start to take a shower and have plenty of hot water, but the water rapidly cools off as the cold water mixes with the hot in the top of the tank.
When I called another plumbing shop and discussed my problem with the owner, he agreed that my symptoms indicated a problem with the dip tube. When his plumber disconnected the supply lines, he found the dip tube had not been changed as the original installer claimed, and the supply pipes were connected backwards.
So we had been drawing hot water off the bottom of the tank; as the cold water entered the top of the tank and settled to the bottom it diluted the whole tank of hot water. We did not experience as rapid a drop in temperature as would happen when the dip tube drops off, but we certainly had not been getting the benefit of a full tank of hot water.
As soon as the pipes were installed properly, the water temperature jumped to over 155 degrees, and I was able to lower the thermostat. Finally, more than one person could take a shower without running out of hot water.
Emergency Toilet Supplies
To advance the toilet carousel use arrows.
Click on product to view details.
Information provided in these documents is provided "as is" without warranty of any kind,
either expressed or implied, including but not limited to the implied warranties of fitness for a particular purpose.