Please explain a "heat trap" to me.


  #1  
Old 01-27-09, 05:49 AM
M
Member
Thread Starter
Join Date: Jan 2008
Location: West of Chicago
Posts: 307
Upvotes: 0
Received 1 Upvote on 1 Post
Please explain a "heat trap" to me.

I just bought the new water heater. It came w/ dielectric "heat trap" nipples. Can you explain how these work? I have also seen piping diagrams depicting a 6" drop in your piping that is called a heat trap...

How does all this work out in the real world? Are these nipples a modern substitute for the old pipe drop scheam? Just curious because I want to do my new install the best I can. Thanks-
 
  #2  
Old 01-27-09, 06:52 AM
M
Banned. Rule And/Or Policy Violation
Join Date: Dec 2007
Location: Chicago
Posts: 904
Upvotes: 0
Received 0 Upvotes on 0 Posts
Heat Trap fittings function as check valves on the hot and cold water lines at a water heater to prevent convective movement of water. They operate by having lighter or heavier-than-water balls which seat on the valve when there is no water flow.
 
  #3  
Old 01-28-09, 04:27 AM
plumbingods's Avatar
Member
Join Date: Apr 2008
Location: Manch-vegas, New Hampshire
Posts: 1,985
Upvotes: 0
Received 0 Upvotes on 0 Posts
Yes, those fittings are a substitute for the old drop pipe method. Either will work just fine.

It's intended purpose is to stop any gravity hot water from traveling up the piping and being wasted.
 
  #4  
Old 01-31-09, 05:52 PM
Terd Herder's Avatar
Member
Join Date: Jan 2008
Location: Northern Illinois
Posts: 277
Upvotes: 0
Received 0 Upvotes on 0 Posts
What brand water heater did you get?
 
  #5  
Old 02-01-09, 04:55 PM
5
Member
Join Date: Nov 2004
Location: CA
Posts: 1,913
Upvotes: 0
Received 0 Upvotes on 0 Posts
Originally Posted by Milemaker13
I just bought the new water heater. It came w/ dielectric "heat trap" nipples. Can you explain how these work? I have also seen piping diagrams depicting a 6" drop in your piping that is called a heat trap...

How does all this work out in the real world? Are these nipples a modern substitute for the old pipe drop scheam? Just curious because I want to do my new install the best I can. Thanks-

Today's heat trap nipples are commonly a little rubber flapper which in essence acts as a check valve. The purpose is to keep heated water from migrating by natural convection up the pipes, where heat would be lost and thus energy wasted.

They are not a true check valve, in that water will flow under system flow demand, but convection does not cause enough force to overcome the 'springiness' of the flapper.
 
  #6  
Old 02-02-09, 10:33 AM
M
Member
Thread Starter
Join Date: Jan 2008
Location: West of Chicago
Posts: 307
Upvotes: 0
Received 1 Upvote on 1 Post
In the end I got the GE from big orange. Made by rheem. Anyway, it seems like a good unit. Works well anyway.


So I installed my copper pipe to these "heat trap " nipples. But in a short while my cold water feed pipe is hot to the touch about 3 feet away from the tank. The hot water pipe is warm, not hot, for about the same distance.

I thought the heat traps would have stopped this. I think I am going to cut in and put the "drop pipe" traps in place. Hope this stops the heat migration. I also plan to insulate these pipes. Hope this all will help out.
 
  #7  
Old 02-02-09, 10:43 AM
Gunguy45's Avatar
Super Moderator
Join Date: Dec 2007
Location: USA
Posts: 19,281
Received 7 Upvotes on 7 Posts
Well, you'll still get some heat conduction through the pipe material itself, I would think. The heat traps just prevent natural convection in the water inside the pipes.
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: