Multiple problems with water heater(maybe)?

[bcdudley]

Just moved into a 30 year old house about 6 months ago. The water heater was installed in 1998. Today, my wife told me she thought the floor felt a little warmer than the rest of the floor right next to the water heater. She was concerned this may be a slab leak. I could not tell any difference and a infrared thermometersaid it was the same temp. I was looking at the water heater and I noticed that the cold water intake was just as warm as the hot water pipe.

One other thing, the hot water pressure has always been really low since we moved in. If we try to run the bath tub and washing machine (with cold water only), the water coming out of the tap is just a trickle.

Cold water pressure is generally fine unless we run the sprinkler system.

I am wondering of there are some crossed pipes or something.

Any suggestions on where to start?

[jadnashua]

There are heat traps that can be installed on the hot and cold piping to minimize convection currents that could heat the water, but conduction often wins, regardless of whether the tank has them installed. But, one symptom of a bad or corroded or partically blocked one is low flow. But, you're talking about cold flow, which should have nothing to do with the WH.

On a older house, (this isn't all that old) some of the piping or at least a connection or two could be galvanized iron pipe. At 30-years, the inside of the pipe could be about the size of a pencil. Plus, if the water gets turned off, then on again, the inrush of the water might dislodge some rust or other crud and plug up aerators and any small orifice.

Most WH don't last that long, so it may be time to consider a replacement. Slab leaks can be a pain. Double check your water meter, see if it's moving when everything is turned off. You might check before you go to bed, then again in the morning before flushing the toilet or showering.

[hj]

You have more problems that we can diagnose over the Internet. IF the hot and cold pipes are the same temperature, then you do not have an underfloor slab leak. There are several different possibilities for the pressure problems, but we do not know enough about your house to tell which, if any, apply to you.

[LLigetfa]

hj is right. If both pipes are warm, there is no leak.

One other thing, the hot water pressure has always been really low since we moved in. If we try to run the bath tub and washing machine (with cold water only), the water coming out of the tap is just a trickle.

Which water trickles, the hot, the cold, or both? What is the elevation difference between the washing machine and the tub? Upstairs/downstairs?

I don't know if many water heaters came with heat traps in '98 but if yours has them, sediment could be preventing proper operation which could restrict flow.

[bcdudley]

The house is one story so everything is at the same level. The washing machine is closest to the water heater followed by the sink and then the tub. The low pressure is only on the hot water side unless the sprinkler system is on, then everything is low.