Wed, 22 Apr 2026 13:16:31 +0100 https://www.greenbuildingforum.co.uk/newforum/ Lussumo Vanilla 1.0.3 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17483&Focus=296315#Comment_296315 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17483&Focus=296315#Comment_296315 Thu, 02 Jun 2022 11:42:14 +0100 jamesingram
As Ive now pretty good supply of constant hot water via PV heated HW storage I'm wondering again if filling my veg steamer etc with mains cold tap water is really necessary and missing an energy saving trick .
Its being boiled isnt it , What are the other negatives involved ?


Whats peoples views ?]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17483&Focus=296316#Comment_296316 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17483&Focus=296316#Comment_296316 Thu, 02 Jun 2022 12:48:47 +0100 owlman https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17483&Focus=296317#Comment_296317 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17483&Focus=296317#Comment_296317 Thu, 02 Jun 2022 13:28:34 +0100 tony
There are heat losses associated with hot water storage, this equates to energy used. If solar then you win. Otherwise you loose.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17483&Focus=296321#Comment_296321 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17483&Focus=296321#Comment_296321 Thu, 02 Jun 2022 14:08:07 +0100 jamesingram temperature wise, out the tap its currently 60. immersions stats are up to the max and supplied only ever by Pv dump. back up is gas primary circuit set at 50
2x120 Tanks, probably alway use one per day so storage is never more than 24hrs]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17483&Focus=296322#Comment_296322 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17483&Focus=296322#Comment_296322 Thu, 02 Jun 2022 16:51:43 +0100 Cliff Pope Freshly heated and boiled water will be oxygenated, water that's been standing hot for hours will be dead.

I had a land lady once who always set the kettle over the pilot flame on the hob for me while I was at work. It was nicely hot when I got home, but not as nice as fresh water.

I don't know whether the same would apply to potatoes, veg etc.

Another point is the hot water will surely have dissolved copper from the pipes? I don't want my insides stained blue :)]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17483&Focus=296323#Comment_296323 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17483&Focus=296323#Comment_296323 Thu, 02 Jun 2022 17:05:22 +0100 Peter_in_Hungary https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17483&Focus=296325#Comment_296325 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17483&Focus=296325#Comment_296325 Thu, 02 Jun 2022 19:14:59 +0100 WillInAberdeen
Not a medic, but most infection issues seem to be about cumulative risk: how often you are doing it, any other risk factors (existing health issues), mitigation measures (boiling it), tolerance of risk (drinking it yourself or serving it to others), etc


It's perhaps a good use for the lukewarm water standing in the pipes before it runs hot enough to wash up. In our case that's a largish volume (I didn't design the plumbing) so I wouldn't want to run the tap hot just to fill the kettle without doing anything else after, because it would leave a hot volume wasted in the pipes to cool down.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17483&Focus=296330#Comment_296330 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17483&Focus=296330#Comment_296330 Thu, 02 Jun 2022 22:36:52 +0100 djh Posted By: jamesingramIve always considered it a no no to use the headed cold water tank supply thats then heated in the hot water storage cylinder for hot drinks or cooking , boiling veg etc.

As Ive now pretty good supply of constant hot water via PV heated HW storage I'm wondering again if filling my veg steamer etc with mains cold tap water is really necessary and missing an energy saving trick .
Its being boiled isnt it , What are the other negatives involved ?Yes, me too. Or at least in our previous houses. But now we don't have a cold water tank, and we don't have a hot water cylinder either. For all the good reasons that you state. All the water we drink, cook with or shower in is fresh from the mains, as is the water we flush the loo with.

But it is all softened, because we live in a hard water area. Hot water is passed through a PHE and heated from our thermal store. Until very recently my wife has insisted on using 'filtered' water in the steamer, but I have finally persuaded her to try using whatever comes out of the hot tap. 'Filtered' is raw tap water that has been through a couple of filters to soften it and strip the heavy metals etc, which is overkill for a steamer IMHO, although I'm prepared to use it for the kettle.

We would never fill the steamer with raw tap water because it would scale up so quickly. But I'd fill it with pretty much any softened water, even if it had been stored, since all the veg is going to see is the distilled vapour.

Making tea is much more critical from a taste point of view. Each to his own. Legionella is a respiratory disease; you don't get it from eating or drinking stuff, but from breathing or showering infected vapour/droplets. You don't get it or anything else from washing utensils either, as long as they are dried and ideally left to dry further for a while first.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17483&Focus=296342#Comment_296342 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17483&Focus=296342#Comment_296342 Sun, 05 Jun 2022 22:17:23 +0100 cjard
I'd say so, when you consider that desalination plants/devices heat water to steam then condense the steam to get pure (distilled) water; the dissolved minerals remain in the water being boiied, rather than go with the steam, so the steamer is cooking your veg by bringing it into contact with hot, pure water]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17483&Focus=296343#Comment_296343 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17483&Focus=296343#Comment_296343 Mon, 06 Jun 2022 00:13:41 +0100 WillInAberdeen
However commercial kitchens are supposed to use a "2-stage cleaning" regime where the washing/drying is reinforced with a disinfectant or steriliser stage. (Cumulative risk tolerability, again, as you learn while taking your Food Safety certificate to help at a street party!).

https://www.aberdeencity.gov.uk/services/environment/food-hygiene-guide#2146

https://www.sciencedirect.com/science/article/abs/pii/S0168160502005408


Steaming food is pretty safe because of the temperatures, but even distilling doesn't produce 'pure' water - the lively bubbles in the boiling water, throw up lots of tiny droplets of the contaminated water into an aerosol mist which drifts along with the steam. Any VOCs end up in the steam too. Again, it's a question of how safe you really want to be, but it does take some extra steps if you need to produce really pure water, say for industrial/laboratory uses.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17483&Focus=296349#Comment_296349 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17483&Focus=296349#Comment_296349 Mon, 06 Jun 2022 13:33:44 +0100 HollyBush Posted By: Peter_in_HungaryFor me it depends upon whether or not the cold storage tank is closed sealed. I have seen many open cold supply tank that had no or very flimsy covers so no way to keep out mice and birds or other unwanted dirt to contaminate the water (including up the overflow pipe)


Peter's message is the big one for me - I have seen dead birds in feed tanks. Do make sure it is sealed in some way.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17483&Focus=296352#Comment_296352 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17483&Focus=296352#Comment_296352 Mon, 06 Jun 2022 16:23:52 +0100 renewablejohn https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17483&Focus=296354#Comment_296354 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17483&Focus=296354#Comment_296354 Mon, 06 Jun 2022 19:02:38 +0100 revor https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17483&Focus=296356#Comment_296356 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17483&Focus=296356#Comment_296356 Mon, 06 Jun 2022 20:42:36 +0100 cjard
Fawlty Towers covered it quite well!

https://m.facebook.com/50shadesoffun1/videos/fawlty-towers-pigs-and-pigeons/465008930666637/]]>