If My Water Heater Doesn't Work, Is Water Still Safe to Drink (if Cold)?

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My water heater has an issue. I still get cold water, but is that safe to drink if the water heater is not working? Thanks!
 

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  • #2
Baluncore
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Why do you need a water heater?
Is it to sterilise the water?
 
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I don't know. Just asking. We only have cold water right now. I figured it would be safe....but I'm not knowledgeable about this stuff.
 
  • #4
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Are you asking whether a defective water heater might contaminate your entire water system somehow?
 
  • #5
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Essentially, yes. I think that's what I'm asking.

Basically, would anything bad happen if I showered with , brushed my teeth with, or used for food prep the water out of the faucet if the water heater is not working and we cannot get hot water.

Can we still use the water that does come out, in other words (even if it's only cold)?
 
  • #6
phinds
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"Broken" water heaters are pretty much always a problem with the heating mechanism. Does nothing to the water.
 
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If your water is otherwise potable, you probably shouldn't be drinking water from your hot water heater. Much depends on the vintage of your plumbing and the properties of your water, but water from the 'Hot' tap tends to have higher levels of dissolved metals, etc. It's not a huge issue, but given a choice... Ironicially, that's probably not true, now that your heater is broken - your hot water has never been safer to drink.
 
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  • #8
rbelli1
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To bypass the issue completely couldn't you just use the cold water tap for cold water and just ignore the hot tap?

BoB
 
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  • #9
Janus
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Essentially, yes. I think that's what I'm asking.

Basically, would anything bad happen if I showered with , brushed my teeth with, or used for food prep the water out of the faucet if the water heater is not working and we cannot get hot water.

Can we still use the water that does come out, in other words (even if it's only cold)?
Your cold water supply comes directly from the water main. For hot water, a branch pipe comes off the cold water supply and delivers water to the hot water heater tank, where it is heated and then delivered to the hot water taps via a separate system of pipes. So the only connection between the hot water lines and cold water lines happens before the water gets to the hot water heater.
 
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  • #10
russ_watters
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My water heater has an issue. I still get cold water, but is that safe to drink if the water heater is not working?
It is generally not advised to drink water from a water heater, hot or cold (but as @Dullard says, the risk is higher when it is hot). Three reasons:
  • Hot water from the tap is generally at a good temperature for promoting bacteria growth: it is warm, but not hot enough to kill bacteria (it is actually legally required not to be for scalding safety reasons).
  • Hot water leaches/dissolves contaminants into it better than cold water does.
  • Hot water lingers in tank longer than in pipes, which, again, enables leeching and bacteria growth.

In a modern and well-maintained system these risks are probably low, but they are worth noting.

https://denverwatertap.org/2017/12/13/psa-dont-drink-cook-hot-water-tap/
https://homeexplained.com/is-it-bad-to-drink-hot-water-from-the-tap/
 
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  • #11
jbriggs444
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Your cold water supply comes directly from the water main. For hot water, a branch pipe comes off the cold water supply and delivers water to the hot water heater tank, where it is heated and then delivered to the hot water taps via a separate system of pipes. So the only connection between the hot water lines and cold water lines happens before the water gets to the hot water heater.
In our house the upstairs bathroom sinks were "upgraded" so that the hot water line is connected through a small electrically powered pump to the cold water line. The pump will periodically run to move a volume of water from the hot water line to the cold water line. This has the effect of moving some hot water out of the hot water tank and into the hot water line and some water from the cold water line into the hot water tank.

Everything is at the same pressure, of course, so the pump does not need to work very hard circulating water through the loop.

The intended effect of this arrangement is that when one turns on the hot water tap in the sink or shower, the water is hot almost immediately -- the hot water pipes being kept full of hot or at least warm water from the tank.

One unfortunate side effect is that cold water drawn from the tap is not cold. Another unfortunate side effect is that the insulation on the hot water tank does nothing to prevent heat being lost from the hot water which is always in the hot water pipes.

If I had it to do over again, there is no way I would agree to have such an arrangement. Even now, it is tempting to simply unplug the pump.
 
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  • #12
russ_watters
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In our house the upstairs bathroom sinks were "upgraded" so that the hot water line is connected through a small electrically powered pump to the cold water line....

If I had it to do over again, there is no way I would agree to have such an arrangement. Even now, it is tempting to simply unplug the pump.
Heh - I've considered doing this retrofit for mine. If I do it, the pump will be on a timer which will turn it on for a few minutes, once a day, at 6:00 am. It would serve the shower only.
 
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  • #13
Janus
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In our house the upstairs bathroom sinks were "upgraded" so that the hot water line is connected through a small electrically powered pump to the cold water line. The pump will periodically run to move a volume of water from the hot water line to the cold water line. This has the effect of moving some hot water out of the hot water tank and into the hot water line and some water from the cold water line into the hot water tank.

Everything is at the same pressure, of course, so the pump does not need to work very hard circulating water through the loop.

The intended effect of this arrangement is that when one turns on the hot water tap in the sink or shower, the water is hot almost immediately -- the hot water pipes being kept full of hot or at least warm water from the tank.

One unfortunate side effect is that cold water drawn from the tap is not cold. Another unfortunate side effect is that the insulation on the hot water tank does nothing to prevent heat being lost from the hot water which is always in the hot water pipes.

If I had it to do over again, there is no way I would agree to have such an arrangement. Even now, it is tempting to simply unplug the pump.
Sounds a bit like the hot water loop you have in large buildings. The hot water is continuously circulated through it so that hot water is quickly available at any tap no matter how far the tap is from the main hot water tank.
 
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  • #14
jbriggs444
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Sounds a bit like the hot water loop you have in large buildings. The hot water is continuously circulated through it so that hot water is quickly available at any tap no matter how far the tap is from the main hot water tank.
Yep, just done on the cheap using existing pipes.
 
  • #15
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I just want to comment on how bizarre this thread is. A simple question with a one line answer: Yes, your cold water tap, if you normally drink out of it, is still safe to drink.

Instead it's several probing questions without a straight, clear answer and then a tangential discussion about contaminants in hot water tanks in general and hot water loops which don't exist in most people's residences.
 
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  • #16
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I just want to comment on how bizarre this thread is.

And for that. . . I'd like to thank you. . ✔
.
 
  • #17
russ_watters
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I just want to comment on how bizarre this thread is. A simple question with a one line answer: Yes, your cold water tap, if you normally drink out of it, is still safe to drink.
I'm not seeing in the OP where the cold water tap is specified.
 
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  • #18
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It is generally not advised to drink water from a water heater, hot or cold (but as @Dullard says, the risk is higher when it is hot). Three reasons:
  • Hot water from the tap is generally at a good temperature for promoting bacteria growth: it is warm, but not hot enough to kill bacteria (it is actually legally required not to be for scalding safety reasons).
  • Hot water leaches/dissolves contaminants into it better than cold water does.
  • Hot water lingers in tank longer than in pipes, which, again, enables leeching and bacteria growth.

In a modern and well-maintained system these risks are probably low, but they are worth noting.

https://denverwatertap.org/2017/12/13/psa-dont-drink-cook-hot-water-tap/
https://homeexplained.com/is-it-bad-to-drink-hot-water-from-the-tap/
This is useful. Thank you for the explanation.

What do you think of just boiling water from the tap - whether cold or hot? Would that be safe/safer?

Or, do you have to use a purifier of some sort (which I don't have). I have traditionally just drank bottled water. Still have some, but down to last six bottles right now. So, if boiling works to make it safe, that'd be cool.
 
  • #19
rbelli1
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The water coming into your home should be safe as is. You should be able to contact your water company and get their test reports. This information may also be on the internet. Independent testing labs will also test the water for you.

Boiling water will kill bacteria and viruses but will do little for chemical contaminants from the source or leached from plumbing at any point from the plant to your faucet. Some volatiles may boil out.

Filter type purifiers will remove various materials from the water. All of them improve the flavor but no general statement can say what else is removed. They may or may not make it safer. They will generally not claim to remove pathogens.

Distillation will give the purest water.

Was there a concern about your water safety before the heater broke? The safety after should be the same as before except for the elimination of issues around the hot water system.

BoB
 
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  • #20
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The water coming into your home should be safe as is. You should be able to contact your water company and get their test reports. This information may also be on the internet. Independent testing labs will also test the water for you.

Boiling water will kill bacteria and viruses but will do little for chemical contaminants from the source or leached from plumbing at any point from the plant to your faucet. Some volatiles may boil out.

Filter type purifiers will remove various materials from the water. All of them improve the flavor but no general statement can say what else is removed. They may or may not make it safer. They will generally not claim to remove pathogens.

Distillation will give the purest water.

Was there a concern about your water safety before the heater broke? The safety after should be the same as before except for the elimination of issues around the hot water system.

BoB
Thanks for the very detailed, response, BoB. No issues with safety before water heater broke. It's fixed now!

Had always been curious and never needed to ask those questions, though. The breakdown led me to ask, so it's good to know for future purposes as well!
 

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