Hot water tank leak

Use garden hose cap:
http://waterheatertimer.org/How-to-replace-water-heater-drain-valve.html
http://waterheatertimer.org/Leaking-water-heater.html
Make sure you are not capping off TP valve:
http://waterheatertimer.org/How-to-replace-TP-valve.html
Identify water heater valve:
http://waterheatertimer.org/Repair-water-heater-valve.html

Gene
h

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

Yes, if you are talking about drain valve:
Identify water heater valve:
http://waterheatertimer.org/Repair-water-heater-valve.html

Do not cap off TP valve or TP overflow tube

Gene
h

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

If the drip is coming out of drain valve: Put a hose cap over end of drain valve.
If water is seeping out of cracked drain vale, then replace it.
If the leak is seeping around previously sealed threads, then tank may be rusted beyond repair.
http://waterheatertimer.org/How-to-replace-water-heater-drain-valve.html
http://waterheatertimer.org/Leaking-water-heater.html

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

Easiest to put hose cap over end of drain.
Open following link for resources and illustrations:
http://waterheatertimer.org/How-to-replace-water-heater-drain-valve.html

If you mean the drain valve, then buy garden hose cap at home center.
Cap will have rubber washer that seals tank.
If drain valve is plastic, the cap may not thread on without sanding down end of plastic drain valve.
Otherwise replace drain valve, which is simple if drain valve is brass, but can be difficult if drain valve is plastic.
Turn off power to water heater: Electric: turn off circuit breaker. Gas: turn knob to pilot.
Turn off water, open bathtub spigot on Hot side, drain water heater, remove drain valve with wrench.
If plastic drain valve breaks while being removed, then 'gently' break out broken part using hammer and big screwdriver.
Buy new drain valve at box store in water heater department.
Put teflon tape on new drain valve threads.
http://waterheatertimer.org/Water-heater-is-leaking.html
http://waterheatertimer.org/Water-heater-will-not-drain.html
http://waterheatertimer.org/Clean-sediment-out-of-water-heater.html

Add a comment for more free help.
Also take advantage of fixya expert assistance live.
For a price, expert works with you while you work on water heater or any do-it-yourself project.
Fixya is always less expensive than a service call.

When you say drain valve, do you mean TP valve?
Two different things: -drain valve and -TP valve

-Drain valve is located near bottom of tank and has hose thread on end.
-TP valve is brass and is located on side of tank tank near top on , and has a pipe that runs down within 6" of floor, or pipe goes into a drain pipe. DO NOT CAP OFF TP VALVE because this is safety outlet that prevents extremely hot water from rupturing tank.
http://waterheatertimer.org/Leaking-water-heater.html

1) If drain valve located near bottom of tank is leaking, it can be capped with a garden hose cap from hardware store-home center. Thread cap on end of drain valve.

2) If TP valve is leaking.
a)Turn down thermostats on water heater
http://waterheatertimer.org/How-to-adjust-water-heater-temperature.html
b)Replace TP valve
http://waterheatertimer.org/How-to-replace-TP-valve.html
c) Install expansion tank on incoming cold water line
Buy expansion tank at hardware-home center-plumbing supply and tee straight out from cold water line and attach expansion tank. About the size of small football.
http://waterheatertimer.org/images/Expansion-Tank-1-82.jpg


4) Mythbusters blows up a water heater for your enjoyment U-tube
Video shows that extraordinary pressure is needed to blow up heater.
This event has only been reported once in past 10 years that I have read, and it blew out side of home. Stats for this type event don't exist in insurance company records, so you are safe - just don't cap off TP valve.

5) Add a comment for more free help.
Also take advantage of fixya phone service.
For a price, expert speaks with you over phone while you work on heater or any do-it-yourself project.
Fixya is always less expensive than a service call.

You can try to crack it open and get a little piece of crud out of there, I'm sure that is all it is, Just get a tray or something to catch the water, It should stop it, If it gets worse, turn the water off to the heater, then open the valve and hope the bigger piece of crud comes out. It is about all you can do, other than drain the whole thing and take the valve apart and replace the rubber in it. Check it out, Hope this helps.

I wrote a page on leaking water heaters with resources and information:
Page lists things to check.
http://waterheatertimer.org/Water-at-bottom-of-water-heater.html

Also run hand over tank to find warm spot that says where leak is coming from
A rusted tank cannot be repaired.

If your tank is rusted out, it might burst open and flood the area.
Hot water inside tank is under pressure.
Turn off heat source to water heater.
Turn off water valve located above tank.
Open tub faucet on hot side and relieve pressure from tank.

You can limp along with a leaking water heater by turning it on when hot water is needed.
For example a shower uses 5-9 gallons hot water.
Turn gas water heater on for 15-20 minutes.
Turn electric on for 20-30 minutes.

To conserve resources with next heater:
http://waterheatertimer.org/9-ways-to-save-with-water-heater.html

You can do the job.
If the valve is plastic, the valve may break off inside the water heater.

The tank forum which is hosted by a professional plumber says, to use a hammer and screwdriver to remove the plastic drain valve: These guys are the pros.
http://www.waterheaterrescue.com/pages/WHRpages/English/Longevity/water-heater-maintenance-tools.html
" If a plastic drain valve snaps, having a hammer, a flat-bladed screwdriver and a towel can get you out of hot water. The towel is to absorb the hot water coming from the heater. You can use the screwdriver and hammer to gently tap the broken plastic piece out of the threads, then install a ball valve drain assembly with pipe-seal tape.
Now another guy at the Tank was saying he drilled out the broken plastic valve.
In any case it can be removed if it breaks.

Install a brass valve.
I just bought one at Home Depot and noticed that Lowes has brass drain valves too.
They're in the water heater department. You need teflon tape or joint compound on the threads.
And if it ever starts leaking, you can put a hose cap on the end, or replace it again.

For professional water heater advice: I go to the tank
http://www.thetankatwaterheaterrescue.com/forums/forum3/

If you are reffering to the drain valve at the bottom of the hot water tank. It may be leaking due to the O ring being cracked or worn out. You can either drain the tank and replace the valve or you can buy a hosebib brass cap and thread it on the existing valve. There is no cause for alarm when doing this as this valve is just to drain the tank when replacing your hot water heater