Unvented hot water cylinder

Annie1960

• drain primary and secondary circuits to hot water cylinder
• disconnect cylinder and remove
• supply and install 210ltr capacity unvented hot water cylinder
• make all primary, secondary and electrical connections as required
• drain and disconnect existing cold water tank and cross connect the mains water supply to the existing cold water down service to make the house mails water fed only
• disconnect existing shower pump
• commission all systems and leave in full working order

£3,700+VAT

Does this seem reasonable?
No brand of cylinder is specified. Should I be asking for a specific brand, or are they all the same?

Also, it does not mention removing the tanks in the loft - are these usually taken away, or are they left in the loft once disconnected?

southcoastrgi

that sounds a bit expensive to me, no the cylinders arent all the same, megaflow are more expensive & imo aren't worth the extra, go with a stainless steel as these are 25 yrs warentee glass lined are only 10 yrs of course these rely on you getting them serviced & the benchmark filled out every yr, & make sure your installer holds the G3 cert as they need this to be able to fit & service unvented, yes its normal practice to leave the tanks in the roof as it's a pita to remove them

I also hope your incoming water supply has been tested for pressure & flow rate ?
the main in the loft will be 15mm & you really need 22mm from the incoming stop tap to the cylinder or you may (will) have probs with the flow rate

Annie1960

Thanks, southcoast.

I hadn't realised there were different types. Do you mean that they all need to be serviced each year, or only some types?

Is there anywhere I can go to look at these? I've never seen them for sale in any of the DIY shops. What shops sell them?

I'm sure pressure will be OK - the whole kitchen floor gets splashed when I turn the cold tap on, it comes out with such force!

mandm65

If you want to go for a really budget cylinder, then look at the main.
It comes out of the same factory as the Megaflo/Santon, and uses the same stainless steel and production tests. The difference is the warranty, Main only has 2 years provided you have registered it whereas Megaflo now has a lifetime warranty.
Like southcoastrgi I'm not a great fan of Megaflos', they're ok but unsure really worth the extra £, it the storage height is an issue than you may find Megaflo taller for the same capacity.
Yes unvented hot water cylinder require yearly service.
HAH.

Annie1960

Thanks, mandm65.

What sort of person would do the annual service, (e.g. ordinary plumber, or GasSafe engineer, or someone else?)

How much should this service cost?

southcoastrgi

either a plumber or an RGI they just need to hold the G3 cert, price depends on the person servicing it no different to various prices for a boiler service


Unvented Hot Water

What is the unvented hot water qualification?

Unvented Hot Water Systems certificate of competence, which complies with G3 of the Building Regulations, Approved Document G and is recognised by Competent Person Schemes for both Plumbing and Heating Installation.


Why do I need to be qualified?

To be able to carry out work on an Unvented Hot Water System installers need to be able to demonstrate there competence by holding a current certificate of competence.


Why do I need to demonstrate my competence?


To install Unvented Hot Water Systems in England and Wales contractors must demonstrate competence in order to either:

• gain registration with a body approved by the Department of Communities and Local Government (CLG), such as the NICEIC Competent Person Scheme, to enable self-certification of work that must be notified to Building Control
• notify all your work in line with the requirements of Approved Document G of the Building Regulations to the Building Control office of the relevant local council where the work is carried out.

southcoastrgi

unvented cylinders are perfectly safe providing the safety controls are tested, here are some of the reasons why they need to be installed correctly & serviced

Annie1960

So where can I go to look at some?

olimain

I'm having the same job done next week but with a 250l cylinder (Telford brand) with a reputable company for just under £3k including VAT. I'm in SW London

Hope that helps. Let me know if you need any other info

Annie1960

Thanks everyone for comments.

I had a plumber who is also a GasSafe engineer here to look at something else, and while he was here I asked him about this. He looked at my (fairly new) boiler (installed by previous occupants), and said it's not suitable for unvented use, so I've put this idea on the back burner until my boiler has to be replaced. I will consider it again at that point.

southcoastrgi

any boiler can be used to feed an unvented cylinder, i'm guessing you have a combi ?

just because he doesn't know how to connect it to a unvented cylinder doesn't mean it can't be done, when & if you decide to go unvented get yourself a new RGI who knows what they are doing