hot water tank drain valve

I needed to replace the drain valve on my hot water tank (dripping). When I removed the old one I noticed that it was white plastic but the drain pipe in the tank is some form of metal, guessing copper. My question is this: would I need to put any plumbers tape on the plastic drain valve or should I leave it be? I have installed it without tape, seems okay, but I'm wondering if it might fail in the future.
A second question: would it be better to replace the plastic drain valve with a copper one? My fear is that without knowing what metal the drain pipe is, putting a copper drain valve might cause some problems.
As always, thanks!
--
edee em
I know the truth is out there but I like to stay in...
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
edee_em wrote:

If the plastic valve isn't leaking now, chances are that it will last until it is opened again. These cheap valves are designed to be used only once -- at the end of the heater's life. If you intend to periodically flush out the tank (extending its life), replace the drain valve with a brass one. Most likely the opening in the tank is 3/4" pipe thread. Seal the new valve with Teflon tape or pipe dope.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

if your going to drain occasionally install a ball valve, the large opeing wouldnt clog.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Use the teflon tape. You can try some plumbers putty if you want, but it's a lot of trouble.

Your choices are metal or plastic. Plastic valves are good for a few uses before they fail. Better tanks *come with* a metal valve. Use a metal valve. They're all brass, as far as I can tell.
--
Steve Bell
New Life Home Improvement
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I put a brass hose cap at the end of my valve. I don' t know why these valves always leak, but it seems like a simple fix to just put a cap.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Right on about the plastic valves being crap. I took my old one apart and found a flimsy o-ring at the end of the stem is all there is to the valve and it had come off, ergo the leak. There really isn't a whole lot there to instill any confidence that it would hold back 50 gallons of hot water!
Thanks for the suggestions, guys. I really appreciate them all!
Edee em
wrote:

I put a brass hose cap at the end of my valve. I don' t know why these valves always leak, but it seems like a simple fix to just put a cap.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.