Potable Water Accumulator/ Expansion Vessel Questions.

[robsant]

I am pretty sure i am going down the route of fitting a accumulator / expansion vessel to increase the flow rate at my property.

After searching and reading on these forums I still am not sure about a few things, and any help would be appreciated. Sorry i do have quite a few questions!

My house is a 4 bed with 2 bathrooms.

1) I think i need a 500 Litre Vessel, does that sound about right?

2) I was hopeing to put the Vessel in the same small room as a new boiler, but that room gets quite hot. Will this mean that water in the vessel will heat up so i will struggle to get very cold water to the taps?

3) With question 2 in mind, will i get a problem with condensation?

4) I assume that quite simply i could plumb in the vessel after the stop cock and then supply the house from there through a flow reducing valve?

5) I have priced up 3 vessels does anyone have any idea which would be the best or another they could recommend? GAH Coldstream 500 £1045 inc vat, Altecnic Ultra Pro Expansion Vessel 500 £760 inc vat, and Reliance Water Controls 500 vessel £1000 inc vat.

6) Finally does any know what sort of maintenance cost or routine is required for one of these vessels?

Thanks,

Rob.

 

[ChrisR]

WHat's the boiler - it shouldn't heat the room much??

 

[robsant]

Ah, it may not be the boiler alone heating the room, in the same room is a tumble condenser dryer

 

[doitall]

Can't see what your trying to achieve, and personally I think your going down the wrong road.

An 500 ltr vessel is big.

Condensation maybe a problem but you can always lag it.

The three makes you list are all good.

They require very little servicing but the life expectantcy is not good.

 

[WDIK]

500Lt

 

[robsant]

Thanks for your responses.

Doitall...

The house has a static pressure of 2bar, with a flow of about 8-10 litres per minute. I have checked with the water board and they say that this is all i will get where i live. I have also checked with the neighbours and they have the same flow. So upgrading pipes wont work.

Ideally i want mains pressure hot water on demand, so looks like accumulator + big combi / thermalstore is only option i think?

 

[doitall]

Thanks for your responses.

Doitall...

The house has a static pressure of 2bar, with a flow of about 8-10 litres per minute. I have checked with the water board and they say that this is all i will get where i live. I have also checked with the neighbours and they have the same flow. So upgrading pipes wont work.

Ideally i want mains pressure hot water on demand, so looks like accumulator + big combi / thermalstore is only option i think?

1. If you have 2bar static and only getting 8-10 Ltr/m then there's something wrong with the mains, either the size is small or the pipe is damaged/crushed, if you are ona water meter this could also be a cause. Whatever you should be able to get 20-30 ltr/m with a decent pipe.

2. A sealed storage tank and pump set would give you 3 bar constant throughout the house.

3. A system boiler and an unvented cylinder or thermal store would guarantee a better system and give a back up when the boiler packs up.

 

[robsant]

There is a water meter in the pavement outside the house, so i assume this is the cause of a low flow rate?

I agree that if possible i would prefer a thermal store, but either way i need to have a much better cold water flow dont i?

So if the meter is the cause and i doubt i can get that taken out, i assumed that an accumulator was the only option. I am quite new to all this but not sure how i could get the 20-30 ltr/min you mention if the meter is the cause?

 

[doitall]

Perhaps the meter is damaged, easy done if someone turns the water on quick instead of loading the pipe first.

What size is the meter and pipe into the house.

And no an accumulator isn't the only option, as I said a sealed storage tank and pump set would be far better.

 

[Biggles..]

Look into the grundfos home booster, presures adjustable and has 200litre store.

 

[robsant]

I will check what the meter is in the light tomorrow.

I have to admit i dont quite understand the sealed storage tank and pump set option. If i cant get the flow to increase from the meter, i assume you mean that i get a large tank say 200-300+ litres and pump the water from there? so as not pumping from the mains.

I there any chance you can you recommend any websites or manufacturers websites where i could read up about this? Is the one in the picture a kit or different manufacturers parts put together?

 

[doitall]

That is a pump from Carter pumps, there are others as well, you should also look on the Grundfos web site for their home booster as mentioned above.

A sealed tank is the same as what you have now but it is sealed, e.g the lid screws on. have a look at dewey waters, if I get a chance tomorrow I'll dig out a few links.

 

[simond]

The GAH unit is well made and designed for your purpose.

The 500 litre size is the optimum in terms of price and performance. If you fit a smaller unit you may exhaust it on occasional heavy use and believe me, the difference between what you have now and after fitment will be very noticeable indeed.

The siting of the unit near to the boiler will depend on the heat loss from the boiler, newer units are much better in this respect. Bear in mind that in the summer most people's cold water storage tanks are in very hot locations.

Good practice says that wherever possible take the kitchen tap feed off prior to the NRV fitted to the accumulator circuits.

There are cases where the use of an electric pump set are the only viable option, but if you have 2bar static then you don't need it. Bear in mind 2bar is 29PSI!

We fit an awful lot of these and have been doing so for some years, in contrast to many others on this forum. We have not had a single accumulator failure. Those thinking of standard expansion vessel reliability may be forgetting the temperatures exposed to a cold water system are very different.

The GAH system uses components in production for many years in borehole applications in the USA; their cold water is very similar to ours

 

[robsant]

simond...

Thanks for the info, i will speak to GAH and get some more info off them.

Doitall...

I have been thinking about your suggestion, will the water be drinkable, if i do as you suggest?

 

[doitall]

Will the water be drinkable.

Does it have to be, your problem is the bathroom area's, and the kitchen sink can stay as is direct to the mains.

A typical installation would be outside in an attached building, back of the garage, cellar etc and consist of the following

The rising mains would enter the building, and serve the kitchen area, a branch would then feed the storage tank, usually through a water softener.

The tank supplies the pump, which supplies all the hot and cold to the bathrooms and utility