Should you drink water from the hot tap?

I seem to remember being told by a couple of people that you shouldn’t drink from the hot taps in your house. One was my Dad, who said that the hot water system in our old house (built 1980) was fed from a tank in the loft which wasn’t covered, and was the final resting place of the occasional bat apparently.

Another was the daughter of a plumber who said that you shouldn’t even drink from cold taps other than the kitchen, because they were fed differently somehow.

That second one I find hard to believe in a house, but the first one seems reasonable. However in our house now, built in 2007, there is no tank in the loft, so the hot water would in theory be ok to use/drink if you were so inclined – wouldn’t it?

It’s fine to drink if you’re thirsty after eating some dust from underneath the fridge.

In my house:

All cold taps come from cold mains except the bath & shower – which comes from the header tank, so you can’t scold yourself with the mixer tap if there is a cut in mains pressure.

All hot taps come from the hot water cylinder which is fed from the tank in the attic (which is covered).

I’ve filled my camelback from a hot tap for many a year.

anything fed from a tank (non-combi hot water, low pressure cold taps -upstairs??), don’t drink.

anything fed from mains (kitchen tap, combi fed hot water, taps upstairs if they are high pressure?), is fine to drink.

Dave

it’s true, loft tanks can be a bit mank – ours doesn’t look the cleanest of environments although I happily brush my teeth using the water from it.

if you have a combi boiler and no tank then the hot comes straight from the main supply at mains pressure and is as safe as the cold.

How else are you supposed to make a cup of tes?

A lot of newere house are mains fed cold water to every outlet now so fine to drink cold from any tap. it used to be just the kitchen sink that was mains fed, and all other outlets from a cold water storage tank (usually in the loft).

The issue is really temperature, and the optiumum temperature fro legionallae and other bugs. Ofter cold water storage tanks in lofts can heta up to optimum range for these bugs.

As for hot water taps, again it is a temperature issue, if coming from a mains fed combi boiler then probably OK, but make sure you run the tap for a bit to flush out the luke warm water.

If from a tank fed boiler. I wouldnt touch it.

One of my colleagues came in the other morning having fished a dead rat out from the cold water tank in her attic.

She’d noticed the water starting tasting funny when she cleaned her teeth upstairs.

Other than that what wwaswas says.

As with alfabus – if it’s mains fed it’s fine, even if it goes through the boiler as with most modern systems. If you have a tank I’d be selective.

Not sure why you’d want to drink from a hot tap, but I wouldn’t advise it. The risk will depend on the type of system you have.

Cold water systems can vary. Sometimes (not as common these days) only kitchen are fed direct. Bahrooms were fed from a cold water tank.

(I think)

As a kid we found a dead pigeon in our cold tank.

Most modern houses like the one we are in now would be fine. Everything is direct mains fed, in the case of hot this is via the combi boiler.

My kids drink the bath water and its done them no harm. When they start behaving I’ll let them have cold water from the tap 😉

Not sure why you’d want to drink from a hot tap

Good point.

My kids drink the bath water and its done them no harm.

Mine did too.

Even whilst going through a phase of stealth pooing in it on a daily basis in the case of my son. (stealth poos are the ones that hide in the bubbles until you take a scoop of water to pour over their heads when they immediately swim into the container so you can tip on them on the childs head)

It was drinking the water that came out of the bath toys when they squeeezed them that made me shudder though – no idea how long it had been sat in there festering.

a hospital i worked at we had our own bore hole, and a large watr tower to store the water in, an engineer told me they had to go up the tower every few months to clear out the drowne pigeons out of it, and as for the chlorine adition was a turntable, with a arm sweeping chlorine powder into the water supply, some days the water was so strong you couldnt drink it.

Oh and you would get a nice greenish crust around the taps.

Not a combi boiler (3 storey house), but no tank either so it must be mains fed.

That’s what I thought btw, thanks folks. I must admit it’s a bit strange to think that the bathroom tap might not be officially drinkable. Who’d go downstairs in the middle of the night just to get a drink?

I must also add that I drank the water from all over the place in the house with the bat trap in the loft, didn’t have any ill effects.

You haven’t watched Fawlty Towers then?

so the hot water would in theory be ok to use/drink if you were so inclined – wouldn’t it?

strictly it’s not potable water

you may not die, it may be more dangerous to cross the road, or you could use the cold tap directly connected to a potable supply

BTW: tanks in the loft should be covered for frost protection

Slightly off topic. In Australia I used to go past a sports field with a sprinkler system.
They had a sign up saying “danger bore water”
What’s all that about?

What’s all that about?

untreated and best not ingested.

danger bore water

if you drink it you turn into TJ

Not a combi boiler (3 storey house), but no tank either so it must be mains fed.

not quite sure how that follows… where is your hot water coming from? If it isn’t from a combi boiler, then it must be being heated in a tank.

Have you got an unvented (aka mains-fed, direct) hot water cylinder and no cold water tank?

If you have, then you won’t have the dead pigeon issue, but I’d still not fancy drinking the water, since it will have been held in a ‘hot’ / ‘warm’ state for ages breeding bacteria.

From a ‘let them eat mud’ perspective, you’ll be fine 99.99% of the time, but occasionally you might get some nasty bug, like legionnaires disease 😕

Dave

It’s being heated in a tank yes, but that tank’s not fed from a header tank in the loft.

Reading the rest of your post – yes, that makes sense 🙂 ta.

You can basically drink it if it’s not been ‘stored on-site’.

An uncovered tank would be worst, a covered one less bad.

In my parents house, there was a water tank that fed all the hot taps, but the cold water was from a rising main – which I think is the key thing.

Isn’t this something to do with Legionaires desese? That’s related to warm/hot water pipes and outlets..

People tend to snuff it if they are in contact (so I’m told)

I wouldn’t do it, I think there it’s something to do with the temprature being a bit hot.

alfabus – you are very very unlikely to get Legionnaires’ disease from drinking water (either from hot or cold tap) but it could be a problem in your shower as you need to breath in the aerosol to get infected.

As others have said cold water tanks (where fitted) in domestic premises are rarely very clean, usually have too big a holding volume, so sit ‘warm’ and with very little residual chlorine present to kill bacteria. Hot water tanks suffer the same issue, and unless correctly set up and running 24/7 will likely have the conditions necessary for bacterial growth.

Even combi systems with no tank have a potential for high levels of bacteria to proliferate. If you know that most bacteria will survive in temperatures you can bear to hold your hand under for more than a minute or so, and that at look warm temperatures many of the most worrying bacteria double in number every 20 minutes and you quickly get high levels, particularly in rarely used outlets etc. I’ve tested samples from hot water systems and I wouldn’t be in any rush to drink them… …although I’ve also tested water coolers and wonder what proportion of ‘work place illness’ is attributable to these bacteria breeders?

although I’ve also tested water coolers and wonder what proportion of ‘work place illness’ is attributable to these bacteria breeders?

HeeHee – we occaisionally have to clean the green algae off our water cooler. The “stale” smelling water gives it away

No.

Shouldn’t drink from a hot tap, even via a combi boiler. The materials that are used within the system are unlikely to be drinking water approved. So ‘risk’ more likely to be chemical exposure than bacteria.

Materials for the potable side are strictly controlled and tested / accredited to not to anything nasty to the water. Hot water system not so. I.e. can use lead solder on joints in heating systems. Also think about the materials that the heat exchangers in the boilers are made from – likely to be aluminium.

Having said that, its unlikely to do you harm once in a while, more likely to be a long term exposure risk.

Drink from any tap that has a mains feed, dont drink from any tap that has water coming from any type of tank be it boiler or water tank in the loft.

Drink from any tap that has a mains feed

true, but think about what else goes on near the tap. Imagine all the nice things that get sprayed onto the bathroom tap when you flush the toilet 😯

You can have a potable water store in a tank.
The project I’m working on at the moment has no mains water. Only way to get water to site meant crossing a motorway. So we have an aquifer supplying water to a tank where it is pumped to the rest of the house. The water is passed through a sediment filter and uv before entering the system.
They were previously drinking the water straight from the well. I went to inspect the well about half a mile away, shone torch in and said didn’t think I’d be drinking it as dead rat floating in it.
Convinced customer to go for a proper clean out and rebuild of well head!

I used to fill the kettle from the hot tap, in the belief it would boil quicker, was I wrong to do so?

Every day thousands die from the result of not having access to safe water, this hot tap issue has to be the ultimate first world problem.

What I want to know is – why fill a camelbak with warm water? 😕

the ultimate first world problem

Spare me the lecture like I’m unaware of the state of the world. I asked out of curiosity. My wife filled a glass of water absent mindedly from the wrong tap, and I told her it might be best not to drink it. She asked why, I only had half remembered facts so I thought I’d ask on here.

Feel free to point out first world problems when I am feeling hard done by or otherwise disadvantaged when I’m really just being spoiled – that’s the point of that particular meme. It doesn’t apply to questions about plumbing.

I think we’re missing the bigger question here which is, does “drinkable” have a special meaning if you say it in French?

slight hijack but a related topic perhaps..

If I dip a lake to fill my kettle when camping.. all those bugs and worms and water fleas that thicken up the subsequent cup of tea.. what’s the nutritional value there.?

Every day thousands die from the result of not having access to safe water, this hot tap issue has to be the ultimate first world problem.

That’s a remarkably dull-witted thing to say when the OP’s question is effectively “is this water unsafe and will it make me sick” and the answer is “yes, possibly”.