Water Heater with Water Off


Any ideas on how long it will take a 40 Gal electric water heater to have a problem with the water supply shut off, pipes drained but water heater full, and electric still on? Or will it not be a problem at all if the water heater was not drained? What would be the worst case consequences?
I'm 4 hours away or I would just shut the power off.....
Thanks for any input, Rich
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

If the water is still in the tank, there should be no problem at all.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Thanks Edwin.... All I did was drain the water in the pipes by opening a lower level sink faucet and venting from 2nd floor so I am pretty sure the water heater is still full. Don't think it could have syphoned the tank. The property is in cold country and I wanted to shut off the water and drain the pipes in case the heat went off so I would only have to deal with the water in the house if there was a problem. I was in a rush and said to myself, I'll leave the water heater on so I don't cause thermal expansion and contraction which I was afraid might lead to cracks in pipes that have been hot for 20 years. Half way to our destination.... I started to think about the tank loosing water from heating with none to replace it. I can drive up and back tomorrow (8 hours) if I have to but can't go back until after Christmas if I don't go tomorrow. Do you think it would hold for 5 days?
Thanks, Rich

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Rich wrote:

How is leaving the water heater on going to have any effect on pipes which are 20 or 40 ft away and full of air? Hopefully, all the water heater is doing is keeping the water in the tank hot, with some waste leakage to pipes within a few feet. I would have just shut it off.
Half way to our destination.... I started to think about the

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Nothing to do with the pipes, keeping water heater on and ready when we get home and preventing joints in the water heater which have been hot all their life from cooling and heating up again which might (unlikely but) develop leaks after they contract when cooling and then expand again when re heated.
Rich ===================================================== snipped-for-privacy@optonline.net wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
For what it's worth, I have a beach house and an electric water heater. I always turn off the water, drain the pipes, and leave the water heater on.
Never had any problem. And I have been known to leave it that way for months at a time.
I wouldn't worry about it.
Rich wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Great to have a response from someone actually doing it this way with no problems.... Exactly my situation.
Thanks, Rich =================================== snipped-for-privacy@gmail.com wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

If the pipes are drained the air in the pipes will compress as much as necessary, so nothing at all can happen. Well, at least nothing more than normal.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

You're worrying too much. I live in Montana and when I go on vacation (two weeks long this past Thanksgiving; it got to -10 here then), I just turn the water main off and set the (gas) water heater control to "pilot". The house is kept at 55 during that time and in the unlikely event that a pipe does break, the water is shut off so there won't be much damage.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Thanks for all the input.... and you're right, I probably do worry too much. We just bought this house last June and it's in NY on the Canadian boarder so it can get cold up there too which is why I shut the water off to minimize damnage if the power goes out and we have no heat.

well with the power to the water heater on. I was worried about the water in the water heater vaporizing and emptying itself but in the essentially closed system it really has nowhere to go, the air in the pipes will compress a bit from the vapor pressure and everything should be fine.
For the future, for week long trips.... after turning the water to the house off and draining the pipes.... better to leave the power to the water heater on - or shut it off??? What do you think?
By the way... your responses have saved me a very long day, Thanks!
Rich =========================== Bob M. wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

What hPPENS IF A ELECTRIC WATER HEATER HAS A LEAK with no incoming replacement water? I assume the elements would burn out?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
You are probably right but I would choose a burned out element instead of a flood as long as it didn't start a fire.
Thanks, Rich ============================== snipped-for-privacy@aol.com wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

Probably. But it might just sit there and glow like a stove element for a month or so, until you get your next bill and wonder why it's $13,276 US.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Related Threads

    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.