Empty Hot Water Heater If Off till Summer?

Reply

  #1  
Old 11-04-07, 01:02 PM
Member
Thread Starter
Join Date: Jan 2004
Location: Harrisburg, PA
Posts: 484
Upvotes: 0
Received 0 Votes on 0 Posts
Empty Hot Water Heater If Off till Summer?

Hey Everyone,

I use an electric hot water heater during the Summer and then switch over to domestic hot water (oil furnace) for the Winter.

Should I empty my electric hot water heater to extend its life? ...or wouldn't that extend its life?

Thank you! -Tony

P.S. Yes, the power is turned off to it. :-)
 
Sponsored Links
  #2  
Old 11-04-07, 03:08 PM
Group Moderator
Join Date: Oct 2004
Location: WI/MN
Posts: 19,290
Received 44 Votes on 41 Posts
I'd leave it full.
 
  #3  
Old 11-04-07, 08:42 PM
Member
Thread Starter
Join Date: Jan 2004
Location: Harrisburg, PA
Posts: 484
Upvotes: 0
Received 0 Votes on 0 Posts
Why?

I thought the rod inside would continue to deteriorate, but not if it's not in water.

-Tony
 
  #4  
Old 11-04-07, 09:10 PM
core's Avatar
Member
Join Date: Jan 2007
Location: Des Moines, IA
Posts: 1,127
Upvotes: 0
Received 0 Votes on 0 Posts
Originally Posted by tony17112acst View Post
I thought the rod inside would continue to deteriorate, but not if it's not in water.
That's quite possibly true, and if so, sounds like a very good reason to leave the WH filled! Its job is to deteriorate. I'd rather replace an anode rod than the entire heater.

At any rate, an interesting question. And on the other side of the coin, draining the water heater is necessary for winterizing a vacation home and I don't hear anything about them failing every 2 years.

I'd be more worried about a family member lighting up an empty water heater and causing a fire.
 
  #5  
Old 11-04-07, 09:39 PM
Group Moderator
Join Date: Oct 2004
Location: WI/MN
Posts: 19,290
Received 44 Votes on 41 Posts
I think you're more likely to get rust if you drain it.
 
  #6  
Old 11-05-07, 06:06 AM
Member
Thread Starter
Join Date: Jan 2004
Location: Harrisburg, PA
Posts: 484
Upvotes: 0
Received 0 Votes on 0 Posts
Thank you for replying,

I'm not understanding how emptying a metal object would create more rust than leaving the metal object full of water.

So are the water heaters on the shelf at Lowe's and Home Depot rusting since they're empy of water? Would those Electric Hot water heaters rust faster than the one that are already installed and filled with water?

If so, why? I am happy to leave mine filled oneveyone's advice, but I just would like to know why.

Thanks folks! -Tony
 
  #7  
Old 11-05-07, 09:21 AM
Who's Avatar
Who
Who is offline
Member
Join Date: Jan 2006
Location: San Jose
Posts: 2,175
Upvotes: 0
Received 0 Votes on 0 Posts
I'd have the cold water coming into the electric water heater. The EWH's hot port would be piped so that it can either bypass the coil directly and feed the hot water domestic piping (summer mode) or alternatively, supply tempered water to the domestic coil (winter mode).

In the winter, the tank's elements would be off but it would give the water a chance to get closer to room temperature before feeding the coil. If you reduce the ΔT for the coil, you increase its capacity. It might not temper it much because of the insulation on the electric tank, but that's the way I'd do it.
 
  #8  
Old 11-05-07, 04:41 PM
Group Moderator
Join Date: Oct 2004
Location: WI/MN
Posts: 19,290
Received 44 Votes on 41 Posts
A dry tank won't rust. A full one won't rust easily either. One that's damp, but not dry after being drained will rust fastest.
 
  #9  
Old 11-06-07, 06:41 AM
Member
Join Date: Oct 2007
Location: Southern California
Posts: 62
Upvotes: 0
Received 0 Votes on 0 Posts
You can drain it, but remember you will never get all the water out unless you disconnect it and pitch it 45 degrees towards the drain valve. Most water heaters are lined to inhibit rust, but I don't know what a small amount of water will do sitting over time to the bottom of the water heater.
 
Reply

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


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