Using hot water from a vented system for the first time in 2 years

[Plumb Line]

Hi all

For various reasons, we haven't used the hot water system in our house for a couple of years. It's a vented system with a tank in the loft.

I want to try it out now but wonder whether there could be any potential problems from Legionella or anything else potentially nasty?

I don't know whether the fact that the water has never been heated over the time means it is not a breeding ground for anything dodgy?

And if there is a potential for nastiness, will heating the water in the cylinder make it all safe again?

Or is the best option to run off enough water so that both the tank in the loft and the cylinder have fresh water in them (I'd rather avoid that but if it needs to happen then so be it).

Many thanks

 

[steadyon]

1. If you have used the tank fed cold, then the water in the cold water storage cistern should be fresh. If not, then I'd suggest draining both.
2. If the cold is OK, then you could probably get away with temporarily setting the cylinder thermostat higher (say 70 degrees) and heating the hot water cylinder until the thermostat kicks in. Let it stand for a while before using, then reset the thermostat. Don't drink the hot even for teeth cleaning until it's had time to refill a couple of times.

 

[Roy_66]

Dear Plumb Line,

I can only give you an amateur answer. From some of the points you raise I would recommend getting in professional help.

In the meantime can you please say the age of the property and if you know the age of the system.

Now this does not make it all ok at all, but does the header tank have a well fitted cover? If you don't already go in the loft to check that and/or are not familiar with the potential dangers then please get professional help in to do all that.

With no proper cover there could be dead animals/birds/insects/dirt in the header. The whole system needs to be checked out, cleaned and re-commissioned by someone qualified.

The other silly question is it electric, gas, wood etc. powered, and has that been out of service. Consider carbon monoxide dangers etc, and please get some professional help as required.

Wishing you clean hot water, and sorry if I sound negative about "having a go". Glad you are asking first though.

Roy

 

[Plumb Line]

Many thanks for the quick responses. Much appreciated.

@steadyon - no, we very rarely if ever have been using the hot taps cold. I think the only time would be when doing so and not thinking about it. So perhaps it will have to be the full drain/re-fill with fresh.

@Roy_66 - to answer some of those points...

• We've got a professional coming in soon, to do a bathroom re-fit and other plumbing work. I didn't want to raise a new point of discussion so didn't mention it, but the reason I want to check the hot water is to see what kind of shower pressure we'd get without a pump. And I need to do that before he comes.
• The property is a mixture of 18th century, 1970s, and 2001. Well, you did ask! The system itself was installed 2001/2002 so around 20 years old.
• The tank has a reasonably well fitted lid, but it's nothing more than a sheet of chipboard!! Not ideal I know, and will replace for a proper lid when getting the work done. When I last looked it in the tank it looked quite clean (to the eye) actually. I'll nip up and have another look shortly.
• It's an oil powered system and we do use it for the central heating, just haven't been using it for hot water.
• I don't thikn you sound negative, I appreciate the advice. I don't tend to ever try and have a go when it comes to plumbing, so I won't be doing any work myself. Just want to check the pressure as mentioned above.

Cheers

 

[cjg]

drain , refill , flush, job done with HOT water,

 

[Plumb Line]

Took a look at the inside of the tank just now, and whilst there I thought I'd take some photos so those with a more experienced eye could say how it looks in the scheme of things. I appreciate not all nasties are visible to the eye though!

We've got vermiculite insulation so I think that's what the white floating bits are.

The underside of the "lid" has a coating of white mouldy stuff, so I took a snap of that too.

Thanks to you all for taking the time to help with your replies.

 

[exedon2]

As you have already mentioned needs a proper tight fitting lid. The 22mm vent pipe needs shortening current would be in water before overflow height.
As for been clean probably as good as it gets white bits polystyrene?
Strictly speaking overflow should be below ball valve.

 

[cjg]

chipboard lid a no no. take them bits of floaters out to save problems later,

 

[Roy_66]

Tank doesn't look too bad considering wrong lid etc.

The vent pipe height (and other aspects of the vent) is very important so get that sorted. I'd also ask your plumber about the overflow. You may need a qualified central heating engineer for that work if your bathroom fitter is just a general plumber (taps etc )

If you are fit and healthy, after all the drain/refill/flush etc. as described I'd do the shower pressure test. Just open all the windows and minimise your time in the room and don't go in the shower. You could wear a good mask if you have one.

Good luck with the new bathroom.

Cheers,
Roy

 

[Plumb Line]

Well, good to hear that it at least looks clean. Taste test next... I've just baled some out and made my partner a glass of squash using it. I'll she if she notices anything untoward

Thanks for all the other tips and observations. Seeing as we're talking about the tank now, I've got some more questions now if you don't mind please. When we get the plumbing work done and the system is drained, I need to have the tank disconnected so that I can change the boards underneath. I'm now wondering what my best option is. Would any plumbers mind giving a rough idea of prices/price differences on the following, to help me decide....

OPTION1 - plumber disconnect pipework to tank, and F+E tank. I will then do the board replacement work. Plumber reconnect all pipework with the tanks in the same places.

OPTION2 - plumber disconnect pipework to tank, and F+E tank. I will then do the board replacement work but build a higher platform for the tank for better gravity pressure. Plumber to extend current pipework for new cold water tank position (F+E wold remain in the same place) and reconnect.

OPTION3 - as per Option 2, but fit a new tank instead of the re-using the old one (with proper lid, and an insulating jacket, plus the ball valve isn't looking great).

Thank you so much

 

[cjg]

He will have to look and talk to you so that a price can be achieved. to suit the job , sorry.

 

[Plumb Line]

Hi all

Thanks for the great replies. And no need to apologise!

I think I'm going to stick with OPTION1 and go for the least intervention and cheapest approach seeing as it's always possible we'll have to get a new heating system at some point in the future anyhow.

- Lid. I'll see if I can get a decent fitting lid, although not sure how likely that is. Do lids tend to be "unipart"? I'll put a couple of pics of the tank itself below.

- Insulation. I'll get a jacket too while I'm at it. A quick look shows standard types tend to be for a 50 gallon tank, whereas mine is 60. But I'm sure I can hunt something down if they exist.

- Cleaning. Would Milton cut the mustard or is chlorine a better option? I was thinking also that while the tank is empty I'll give it a scrub and clean, perhaps with a spray or two of anti-this-and-that spray.

- Overflow. Can't tell from your posts how necessary it would be to change this. Do you think it needs changing or can be left whilst not being ideal? If it does need changing, will that involve a whole new overflow, new hole in wall, etc?

- Vent pipe. Is the fix for that as simple as cutting a little off so it's not as low? Not that I'm proposing I do it! Just curious...

Thanks everyone and have a great week.

 

[exedon2]

Have a look for a bye law 30 kit for your tank if you can get one incudes tank lagging and a tight lid.
Overflow probably as simple as cap old one off external to tank then cutting new hole in correct place with new tank connector.
Open vent just needs shortening simple as.

 

[Plumb Line]

Thanks @exedon2 - very helpful.

Overflow probably as simple as cap old one off external to tank then cutting new hole in correct place with new tank connector.

Would the pipe need to be running down hill from the tank, or least level? If running up hill from the tank, would that defeat the purpose of lowering it? Not that I know anything! Just thinking aloud!

 

[Ric2013]

Thanks @exedon2 - very helpful.



Would the pipe need to be running down hill from the tank, or least level? If running up hill from the tank, would that defeat the purpose of lowering it? Not that I know anything! Just thinking aloud!

Yes, down or level.