all about water tanks

aggi

Hi all, 
recently moved from flat with combi boiler into house with water tanks in loft. I have ventured into loft and discovered 2 tanks. one small one is open and is rank and think it is to do with central heating. The big one is not fully covered ( The lid doesn’t seem to fit properly) and some residue on the bottom is visible. See attached pictures. My question is ‘Is it ok or one/both need attention/ cleaning? Thank you for advice

EssexExile

The little one is the feed & expansion tank for the central heating. The only time you'll come across that water is if you go in the loft! The other one stores your cold water that feeds bathroom taps (usually) & the hot water tank. Don't drink from the bathroom taps.

Otherwise I wouldn't worry about them.

Jonesya

On a typical system, the big tank will be the cold-water header tank which supplies the cold water to your hot water cylinder (and from there the hot water to basins, bath and kitchen sink), it may also supply the cold water to your bath and possibly a non-electric shower, if your shower is fed from the hot water system. It should be covered, to stop flys/bugs/contamination getting in as you will be using the water to wash your dishes, face, bath in etc. 

The little tank is normally the header tank for the boiler system, for the water which circulates around the boiler to the radiators and the heat-exchanger coil inside the hot water cylinder. It does tend to get dirty because it picks up rust and sludge from the radiators and boiler. You shouldn't be coming into contact with this water so the fact it's dirsty/rusty doesn't matter so much, other than affecting the heating system. Again, should ideally be covered to stop stuff getting in.

They should both have covers over them, the proper covers normally come with a breathers (to allow air in and out as the levels change) which have a fine fly guard to stop stuff getting in.

Oh and some other bits to check - the over-flows are clear/not-blocked, no signs of leaks from the connections or valve, that the valves work ok, and if they're in the attic they should really have some insulation around the sides and on the top of the lid (if you fit one!) to stop them freezing in the winter.

Ectophile

I made up lids for my tanks from polystyrene insulation boards - because they were cheap and easy to carry.  The main water tank needed a couple of boards taped together.  It's not pretty, but it helps insulate the tanks, and stops rubbish falling into them.

avoidtheupsidedownbottles

You could take the precaution of using chlorine tablets/granules to sterilise the big water tank so that you are starting with a clean slate and won't catch anything from it -- particularly if it's not been used for a while.

greatcrested

Jonesya said:

Oh and some other bits to check - the over-flows are clear/not-blocked, no signs of leaks from the connections or valve, that the valves work ok, and if they're in the attic they should really have some insulation around the sides and on the top of the lid (if you fit one!) to stop them freezing in the winter.

But not underneath! Allow heat from the house to rise up beneath the tanks - it helps prevent the water freezing in winter. Insulate the rest of the attick floor, plus around the sides of the tanks and the lids.

bigsteve85

avoidtheupsidedownbottles said:

You could take the precaution of using chlorine tablets/granules to sterilise the big water tank so that you are starting with a clean slate and won't catch anything from it -- particularly if it's not been used for a while.

I wouldn’t advise putting any chlorine tablets into your large header tank, as this water is used for washing and cleaning, even though it’s diluted it could cause an irritant if it gets in your eyes while showering or leave a residue on plates or glasses which you could ingest. If your worried about the water shut off your main cold in and turn on your bath cold tap this should drain it with out emptying your hot water cylinder then wipe out the tank with a cloth to remove anything (don’t use any major cleaners) unless it’s a tank cleaner then turn on your mains to refil, but be careful you may experience issues with your ball valve afterwards which could end up needing replacement 

avoidtheupsidedownbottles

bigsteve85 said:

avoidtheupsidedownbottles said:

You could take the precaution of using chlorine tablets/granules to sterilise the big water tank so that you are starting with a clean slate and won't catch anything from it -- particularly if it's not been used for a while.

I wouldn’t advise putting any chlorine tablets into your large header tank, as this water is used for washing and cleaning, even though it’s diluted it could cause an irritant if it gets in your eyes while showering or leave a residue on plates or glasses which you could ingest.

The procedure involves adding the right amount of chlorine for the capacity of the tank, leaving it for the required dwell time, turning off the mains feed, and draining it out through the pipes to sterilise them.  Then you refill the tank and flush out as many times as needed to rinse out the excess chlorine.  

bigsteve85

avoidtheupsidedownbottles said:

bigsteve85 said:

avoidtheupsidedownbottles said:

You could take the precaution of using chlorine tablets/granules to sterilise the big water tank so that you are starting with a clean slate and won't catch anything from it -- particularly if it's not been used for a while.

I wouldn’t advise putting any chlorine tablets into your large header tank, as this water is used for washing and cleaning, even though it’s diluted it could cause an irritant if it gets in your eyes while showering or leave a residue on plates or glasses which you could ingest.

The procedure involves adding the right amount of chlorine for the capacity of the tank, leaving it for the required dwell time, turning off the mains feed, and draining it out through the pipes to sterilise them.  Then you refill the tank and flush out as many times as needed to rinse out the excess chlorine.  

That’s fair enough then, I didn’t understand your process 

avoidtheupsidedownbottles

bigsteve85 said:
That’s fair enough then, I didn’t understand your process 

The tablets come with instructions, but since I didn't mention anything about flushing, your warning was justified