How long do indirect hot water cylinders last

[ross94]

Hi, i am just curious how long your typical gravity fed indirect hot water cylinders last? The house was built in 1998 and for about a month now i have been hearing loud gurgling coming from the cylinder whenever the power shower is used this gurgling only happens briefly and doesn't affect the system in any way, the flow rates and pressure to all taps remain reasonable as far as gravity systems go. What could be causing the temporary gurgling? Also how long does the main cold water storage tank (plastic) generally last? I have never had any problems with the system and still don't but would like to know how long these systems generally last?
Thanks

 

[Mottie]

We had a vented hot water cylinder as well as a plastic storage tank in our house when we moved in in 1990 and only changed both three years ago when we converted to an unvented system. They were both working fine when they were removed.

 

[vxxbcks]

I just replaced a plastic cold water tank installed in 1971. It was actually still apparently fine but had no lid.

 

[lostinthelight]

I installed a vented heating system in 1974 and the cylinder was still fine when the present owners replaced it with unvented in 2015.
My present property was installed at the same time and an internal leak between the Dhw and boiler water developed in 2014 which caused the expansion tank to overflow.

 

[ross94]

Thanks, from what I have gathered it seems they are pretty bulletproof providing you don't split the tank when changing the immersion for instance. I wonder what is causing the gurgling? Apart from hearing this i have never had any problems with the system.

 

[fixitflav]

Thanks, from what I have gathered it seems they are pretty bulletproof providing you don't split the tank when changing the immersion for instance. I wonder what is causing the gurgling? Apart from hearing this i have never had any problems with the system.

How is the pipe to the shower taken from the HW cylinder? If it's from the vent pipe in the loft, I believe the recommended way is to arrange a section at 45° and tee off downwards from that, to avoid air going to the shower. If that's not the case, it might be the reason.
But having said that, I've had 2 houses where it's just tee'd off the vertical vent pipe, one I did myself years before hearing about the recommendations (if they existed at the time), and where I am now, like that when I moved in. Neither gave any problem.
Edit - should have added, both those are gravity showers. Maybe a power shower would be more likely to gurgle, due to higher flow.

 

[Gasguru]

Post a pic of the top of the cylinder...might have a Surrey flange etc and the air is building up due to scale.

 

[iateyoubutler]

I was having some work done on my system on Monday, and I asked that exact question as mine is at least 20 years old, and basically it is just a lottery. Some only last 5 years, some last 50 years. Too many variables I suppose......

 

[oldbutnotdead]

Copper cylinders for a long time- the one i pulled out of my old house (put a combi in) is at least 35 now, still holds water & heats fine (repurposed onto a woodburner system). Plastic tanks 30 and also fine.

 

[ross94]

Post a pic of the top of the cylinder...might have a Surrey flange etc and the air is building up due to scale.

Hi sorry pictures not available, there is no surrey flange, its just one 28mm pipe leaving the top of the cylinder where it then connects to a tee which from there goes up to the vent (22mm pipe) and then down to the system (28mm pipe).

 

[ross94]

If it also helps i have googled my postcode and it appears i'm in a soft water area.

 

[ross94]

How is the pipe to the shower taken from the HW cylinder? If it's from the vent pipe in the loft, I believe the recommended way is to arrange a section at 45° and tee off downwards from that, to avoid air going to the shower. If that's not the case, it might be the reason.
But having said that, I've had 2 houses where it's just tee'd off the vertical vent pipe, one I did myself years before hearing about the recommendations (if they existed at the time), and where I am now, like that when I moved in. Neither gave any problem.
Edit - should have added, both those are gravity showers. Maybe a power shower would be more likely to gurgle, due to higher flow.

Hi, the powers shower just tees off where the hot and cold pipes enter the bathroom from the floor no pipes come from the attic to the shower.

 

[lostinthelight]

no pipes come from the attic to the shower.

If a gravity supply to the shower, is there no dedicated pipe from the tank?

 

[ross94]

If a gravity supply to the shower, is there no dedicated pipe from the tank?

Hi, not sure what you mean? The cold supply comes down from the attic via the airing cupboard where the cylinder is located, from there the hot and cold pipes go under the floor to the bathroom. The power shower is mira vigour which has a small pump built into it.

 

[ross94]

If you perhaps mean if there is a separate pipe from the tank dedicated for just the power shower then no, it's just a hot and cold from the airing cupboard which supplies everything in the bathroom.