Thursday, September 11, 2014

A Little Information about Maintaining Dual Hot Water Systems

The trees and the grass in the lawn are still arrayed in the deep greens of late summer, but the corn and beans have begun to turn here, and my nephew (four years old) announced last weekend that harvest is coming soon.

He is indeed right.  The weather turned sharply cooler this week too, so my thoughts are turning toward more regular use of the cookstove.  One of the aspects of having the stove steadily fired that I'm really looking forward to is having it supply our hot water.  I'm looking forward to this because it results in such a savings on our electric bill and because the water that comes out of the tap is so much hotter than what we have our electric water heater set at.

Having dual hot water systems creates for us a unique set of maintenance routines.  Last year, we turned our electric hot water heater off in late September and didn't turn it back on again until late May.  It was the second heating season in which we had turned off the electric hot water heater for an extended period of time.

Before we had installed the Margin Gem with the water jacket system, I was telling my uncle about our plans to shut off our tank-type hot water heater during the winter.  He didn't think this was a good idea at all.  He works as an electrician and has seen a number of vile occurrences in people's homes and said that the inside of a turned-off water heater is the beginning of all kinds of nasty things.  I, however, am unwilling to heat water that we are not intending to use, so I went ahead with turning off the electric water heater. 

What has happened each winter, though, is that the water in the electric hot water heater does sour after about the third month of it being off.  This is not a humongous problem, however.  Both the electric hot water intake and supply lines are equipped with gate valves about a foot above the water heater, so those are both shut off.  When we are far enough into the spring that we are going to use the electric hot water heater, I drain and flush the tank, let it fill again, and turn it on.  Initially, the water does have a slightly objectionable smell to it.  After the water heater has been on for a couple of days, I completely empty the tank again, but since it is hot water this time and I am so frugal, I empty it by washing clothes in hot water in the top-loading automatic washer and the wringer-washer.

Now, because I fear the same situation happening in the water heating system attached to the cookstove, I make sure that we use the Margin Gem at least once a month during the summer season.  We make sure to switch the valves in the water lines so that the water heated by the cookstove is used, thereby circulating fresh water into the system.

I don't want the water in the wood heated system to sour because there is no easy way to drain the system.  The Vaughn range boiler has a tapping on the very bottom of the tank which would have been ideal for a drain valve.  However, due to the low height of the legs on the bottom of the tank and the fact that our tank sits on a marble slab, the plumber could not attach a fitting to the bottom of the tank. 

A photo of our range boiler before it was attached
to the Margin Gem range.

I think that what I'm going to try to do this winter is to occasionally circulate fresh water through the electric hot water heater by setting the top-loading automatic washing machine to the hot water cycle, but washing a load of clothes in the cold water that would come from the turned-off water heater.  I can't use the high-efficiency washing machine in this scheme because it senses the water temperature and heats what has come into the washer to the temperature that it desires according to its setting.  Hopefully, this plan will alleviate the easy but inconvenient task of draining and flushing the electric hot water heater in the spring.

Of course, we use well water here on the farm.  What I'd like to know from my readers is whether this situation as I've described it would happen to people whose homes are served by chlorinated water.  Does chlorinated water ever sour in a turned-off water heater?  If you have a range boiler system which is hooked up to a chlorinated water supply, are you able to leave your wood-fired hot water system unfired for the entirety of the summer without any adverse effects?  Please let me know by utilizing the comments section below.  Thanks for your help!


  1. I've no experience with swapping out hot water sources, so I can't comment on that. But I have, a couple times, filled water bottles with tap (city) water, and then forgotten them. A month later the water doesn't quite taste right, but isn't nasty, two months and its getting nasty....

  2. I have well water but have filled unused canning jars with water treated with the recommended amount of bleach for drinking water storage purposes (I think it's 1/2 tsp per gallon - not much). I filled them in the fall and, when I needed those jars in the summer the water looked and smelled like city water.

    1. Did you water bath the jars or put boiling water in them, or did you just fill them and screw the lids on tight? I've read about people actually canning water to help keep the jars clean until they are used for food again, thereby also creating a reserve of water in case of emergency.

  3. I read once that you should never have empty jars on the shelf - fill them up with water and water-bath can them to always have an emergency water supply - not to mention clean jars at the ready.

    But no, I just filled them up and added the recommended amount of bleach. I didn't can them because the
    Price of lids has gotten ridiculously high. I figured I could reuse the lids with the bleach method. I did have a couple of lids that had some rust spots. I think the lids are just cheaply made nowadays. Other than those few it worked out well and when I used the jars for canning I just poured out the water and the jars were ready to use.

    Full directions are on the CDC website, but I can't post a link using my phone.

    You use 1/8 tsp. bleach (or 8 drops) per gallon of water. I mixed using a one gallon pitcher then just poured into canning jars.

  4. Jim,, for several decades my wife and I owned a cottage on a lake in southern Maine. Every fall I would drain the electric hot water heater completely. We never had a problem with a sour smell and our tank is going strong after 30+ years. I think that storing water in your tank might be the problem with a sour smell.

  5. Another thought ,, how old is your electric tank & anode rod ? Does the anode rod need to be replaced ? When they fail they cause the water to smell like rotten eggs.

  6. Thanks for the ideas, Eric! My gut reaction is to believe that the situation in your second comment is more likely since, in effect, we store water in the Vaughn range boiler too and it doesn't sour. I'm going to have to do some research about our electric water heater.