Warm water runs out quickly

Users who are viewing this thread

Mad Plumber

Mad Skills
Messages
248
Reaction score
7
Points
18
Website
www.terrylove.com
When I first turn on my cold water in the
morning it comes out very warm and after 15 to 30 seconds it gets
cold. My thermostats are set 140 for the top and 142 for the
bottom. I have a well and the pump is set to come on at 40 lbs and
cut out at 60 lbs and my pressure tank has 38 lbs of air. I also
run out of hot water if I take a 12 minute shower. It did not used to
run out that soon. I replaced the cal rods in the tank and checked
the fill pipe. (It goes almost to the bottom of the tank). I have a 40gal tank with electric heat. . There is no sediment in the tank. I am 83 years old and am a retired dentist and have done all
my own plumbing and electrical for 50 years. I am stumped. HELP!!!
Ralph M
 

Leejosepho

DIY scratch-pad engineer
Messages
2,483
Reaction score
0
Points
36
Location
200 miles south of Little Rock
Website
www.nonameyet.org
When I first turn on my cold water in the
morning it comes out very warm and after 15 to 30 seconds it gets
cold.

Convection might be warming the supply line above the water heater.

My thermostats are set 140 for the top and 142 for the bottom ...
I also run out of hot water if I take a 12 minute shower. It did not used to
run out that soon.

Maybe those thermostats have become weak and your water is not actually that warm when they shut off.
 

Redwood

Master Plumber
Messages
7,335
Reaction score
13
Points
0
Location
Connecticut
Hi Ralph,
There are a few possibilities.

1 Do you have a hot water recirculation system?
These are to assure that hot water is right at the tap without waiting for it.
Sometimes if a check valve fails in these systems cold water can feed up the recirculation line and cause this.

2 Do you have single handle faucets installed either Mixet or, Moen brand?
Some of these when they fail can create a hot/cold cross connection and still appear to work.

3 Have you had any plumbing work done that is unfinished I.E. Delta R-10000 universal valve without the cartridge installed. This is a common hot/cold cross connection.

4 Do you have any fixtures anywhere where the hot and cold may be turned on together but the outlet can be shut off?

5 When was your water heater installed? in the 90's many water heaters were sold with defective dip tubes. Click here for information on defective diptubes includin serial numbers of affected units

6 Check the upper and lower elements and T-Stats of your water heater to make sure they are operating okay.

7 If you have a tempering valve on the output of the water heater make sure it is operating properly.

honeywell_tempering_2.jpg


Hope this helps you out.
 
Last edited by a moderator:

MACPLUMB

In the Trades
Messages
1,080
Reaction score
83
Points
48
Location
HOUSTON, TEXAS
I WOULD FOLLOW REDWOODS POST ! !

9 TIMES OUT OF 10 IT'S A BAD LOWER ELEMENT. ie. IF THE UPPER ONES IS OUT THEN YOU HAVE NO HOT WATER, IF JUST THE LOWER ELEMENT IS OUT THEN YOU ARE ONLY HEATING THE TOP HALF OF THE TANK. IN OTHER WORDS ONLY 20 GALS. OF HOT WATER

THE OTHER 1 TIME IS LIKE REDWOOD SAID YOU HAVE A BAD CARTRIDGE IN A FAUCET,

THEN CHECK THE OTHER THINGS
 

Kordts

In the Trades
Messages
547
Reaction score
1
Points
0
Location
exurban Chicago
12 minutes times 2.5 gpm = 30 gallons of hot water. That's about right. His showerhead might be an older one that doesn't restrict to 2.5.
 

hj

Master Plumber
Messages
33,603
Reaction score
1,042
Points
113
Location
Cave Creek, Arizona
Website
www.terrylove.com
water

We do not have enough information. Is this a house with a slab floor? Both problems can be caused by a cracked hot water line under a concrete slab. Otherwise, and possibly even then, we would have to be there to see what could be causing the problem.
 
Top
Hey, wait a minute.

This is awkward, but...

It looks like you're using an ad blocker. We get it, but (1) terrylove.com can't live without ads, and (2) ad blockers can cause issues with videos and comments. If you'd like to support the site, please allow ads.

If any particular ad is your REASON for blocking ads, please let us know. We might be able to do something about it. Thanks.
I've Disabled AdBlock    No Thanks