Cold water accumulator/potable water expansion vessel

[Juup]

Hi Steve,

This is very interesting info. What we can perhaps establish, then, given it has worked fine over a three year period at ours, is that an Altecnic (its an Ultra Pro 300) will dispense the water out of the top end - even when it is not intended to be done that way

Here's a photo:

http://www.stelma.org.uk/DSC01522.JPG

Yes, having a pressure gauge in the top connection instead of the outlet would make a lot of sense. I wonder, then, whether we have gotten poorer performance from the vessel as a result of how it was connected, and as Steve suggests this may explain the black residue. I also wonder how many Altecnics are installed incorrectly up and down the country. When we got ours there were no instructions as to how it should be connected as an accumulator.

Juup

 

[steve32]

i have the mi's for a gah dualstream on pdf if you put your e-mail in my profile i'll e-mail them they show an accumulator with an un-vented cylinder the connections are the same for all accumulators it,s best to connect them in 22mm as far as possible even if the incoming mains is only 15mm if used on a combi.

i cannot open the photo

Steve

 

[Juup]

Here is the photo Steve,

Untitled

• Juup
• 7 Jul 2010
• 1

I have put my email into your profile. It would be great to receive this - it would be god to get the install of the new coldstream right.

Juup

 

[steve32]

only the bottom connection should be used


mi's sent

steve

 

[Agile]

This thread has beecome sidetracked.

The OP has an ideal situation for an accumulator, a high static pressure and a poor flow rate.

however, the problem arises because they for some reason must time their showers to overlay. The effect if that is that unless complicated N/R valves are installed an accumulator will have little effect.

Even when usage is better suited there are cost implications that might mean an accumulator is costing about £350 pa to use/replace.

An upgraded mains connection has none of these issues, is quiet and does not need maintenance.

Tony

 

[simond]

A GC450 will run two showers no problem, until you've shifted in excess of 200 litres.

Anybody using this amount in two showers needs to think about the water they are wasting.

I don't understand the comment about non return valves and £350/yr. An accumulator should last in excess of 10 yrs if you buy a good one - - and plumb it in and set the pressures correctly.

 

[Agile]

Simon, I dont think that you read this!

I just this afternoon ordered a Coldstream 500 from here:

The price: 763 pounds (including VAT) and less than 10 pounds for delivery. This is a good 300 pounds less than elsewhere, so I half expect to receive a phone call soon to tell me the price quoted online was wrong, or at the very least that the delivery cost is significantly higher.

Juup

His previous unit was only installed about three years ago and with installation will be making the annual cost very high.

The OP must overlay two shower usages. That means that the accumulator would be exhausted during the first shower. Thats unless the accumulator was isolated from feeding into the first shower so that it could only supply the second shower. Not impossible but does require good quality NR valves.

Tony

 

[simond]

Tony

I think we could be misunderstanding each other.

The accumulator will run two showers if its a GC450, given the pressure quoted earlier on. The whole point of them is to allow multiple draw offs -eg: two showers to be run simultaneously.

The flow rate will be massively increased for the first 200 litres drawoff, which will give you two very good showers each lasting 7 mins (@14l/m). As you get to the end of the boost the performance reduces.

There is only one NRV required in an accumulator install and that is on the incoming CW main, to prevent the accumulator from boosting the neighbours if the supply pressure drops in the morning.

 

[Juup]

Hi Tony,

Yes, I will now replace an accumulator that is only three years old. However, it would be unfair to use this as an indication for the high cost of an accumulator, for two reasons.

1. My current accumulator still works just fine. The black residue lasted for about three days and now things are fine. It may simply have been some muck collecting somewhere else in the system. Sure I am worried and yes, it could be the accumulator, but no way of knowing for sure without more investigation.

2. My accumulator is likely installed incorrectly. See exchange with Steve earlier.

Why, then, am I replacing? Why not just redo the connections on my existing Altecnic? I think because I can afford the expense, like to improve the house in various ways, and wish to get the added capacity of the larger coldstream.

If I had proper professional advice to begin with I would probably have installed a larger accumulator 3 years ago, with the correct connectons, and not be replacing it now.

All that said, I won't tell my friends and neighbours that an accumulator is the best solution in all cases. We have the necessary pressure on our mains to effectively run an accumulator. We also have the space to house it. We use water in particular ways, and the accumulator is feeding certain parts of the house strategically to respond to our needs. Every situation is different.

Juup