New Unvented System

[jonnydarcy]

Hi,
just wondering whether any of you out there could indicate whether I'm getting decent value or not. I have a 15-20 year old vented cylinder central heating system (I have a 5 bedroom, 3 bathroom terraced house). I'm looking to replace this system with an unvented system. I have excellent mains pressure (3bar and 25+ litres/min flow) and am not looking to resposition the tank or boiler at all.

I plan to replace my system with the following:

Worcester 40CDI Conventional Boiler
Megaflo Eco 250i hot water storage vessel

I will also have the system powerflushed of course but over and above a couple of extra bits of hardware, that's about it.

I appreciate that it's difficult to quote accurately without knowing the full details but is anyone able to indicate roughly what the cost to install the above would be?

Thanks in advance

BTW - I live in London so labour costs will be slightly higher I would expect.

 

[CBF]

i wouldn't fit either both are too expensive

for the boiler

http://www.remehaheating.co.uk/
http://www.remehaheating.co.uk/home/system-boilers/why-choose-a-system-boiler

for the cylinder

http://www.ariston.com/uk/Viewdoc.aspx?co_id=361

 

[jonnydarcy]

Ok but in terms of installation costs?

Let's say that the boiler and tank plus other hardware is @ £3,000. Given the straightforward nature of the job, what would be a reasonable cost to install this system? £500? £1,000? £2,000? etc

BTW of the 7 tradesmen I have spoken to regarding this work, only British Gas (British Gas 330+ High Efficiency Boiler) has recommended anything other that Vaillant or Worcester Bosch. To opt against this general advice makes me feel nervous.

 

[CBF]

Ok but in terms of installation costs?

Let's say that the boiler and tank plus other hardware is @ £3,000. Given the straightforward nature of the job, what would be a reasonable cost to install this system? £500? £1,000? £2,000? etc

BTW of the 7 tradesmen I have spoken to regarding this work, only British Gas (British Gas 330+ High Efficiency Boiler) has recommended anything other that Vaillant or Worcester Bosch. To opt against this general advice makes me feel nervous.

the british gas boiler is really a glowworm re-badged, Vaillant are having a few probs at the mo i just give you one example but i'm sure if you goggle you will find loads more.
http://www.reviewcentre.com/reviews120952.html

WB are good boilers but over priced, they are also a nightmare to work on which reflects in the repair costs, just because something is the brand leader doesn't make it the best, i'll give you an example for a prv change, Halstead (worst boiler ever made always breaking down) 15 mins, WB 3 1/2 hrs (because to get at it you need to take out the pump, disconnect the main heat exchanger etc etc), to change the EV on some models if you haven't got the correct distance either above or to the side you need to remove the boiler from the wall as the EV is at the back.

megaflows are the same way over priced, yes they have an internal expansion but if you lose the "bubble" then it needs to have that re-placed, you pays your money & you takes your choice just don't believe everything you are told.

as for installation costs the best people to tell you are the ones that have seen it

 

[jonnydarcy]

Thanks for the reply.

That's a bit of a minefield for the customer don't you think?! How do they make a decision about which boiler/tank combo to go for?

 

[dcawkwell]

Take a look at the glow worm ultra power will do both jobs all in
the one box.

 

[CBF]

yes i totally agree it is a mine field & you could ask 10 different RGI's & get 10 different recommendations on boilers, nearly every RGI will reg the boiler with the manufacturer & everyone will get something back from them wether it is points on a card, free gifts etc etc, i try to give the best advice to my customers & if something is rubbish or has a prob then i will tell them, i don't believe in spending more money than you need too when another product will do the same or better, if i thought Remeha were rubbish i would tell you it's no skin off of my nose what you fit i'm not doing the job, i just think you are being blinded by the installers that say yes it's the best you must fit this, why do you think WB are one of the only ones not to use a stainless steel heat exchanger ? then when their sales went down they offered a 10 year warrantee on that, because it looks good & if they have to change one or two then that's small fry in comparison with the amount they sell because people are thinking they are getting a good deal with a 10 yr warrantee.

i only signed up yesterday & i'm guessing i am gonna put a lot of noses out of joint on here because the only thing you get from me is the truth good or bad.

 

[CBF]

Take a look at the glow worm ultra power will do both jobs all in
the one box.

except it won't because if you go for the 100 ltr version after 3 mins it reverts to a combi with only 12.5 ltrs/min flow rate & that's in the summer, plus it's way way too dear & i'm guessing that would go in the airing cupboard which would mean re-routing the gas & flue, something the OP doesn't want to do

 

[sherbert]

what your going for is top end spec although I feel that your mains pressure/flow rate is a bit low for 3 bathrooms??

Get a Worcester accredated installer to fit the boiler and your get a 7 year warranty on the boiler .... just needs to be serviced yearly

Im not that keen on megflows as has been said they have to be drained every year to maintain the air gap for expansion ........ I prefer a cylinder with a seperate expansion tank although these can go resulting in a new one needed .. expansion vessel that is

Dont go for a combi of any description ........ with 3 bathrooms youll be disappointed although you may need a bigger water main as 3 bar is not really enough for 3 bathrooms IMHO

But all in all your in the right direction with what you want

 

[jonnydarcy]

Thanks for all this advice, keep it coming.

I believe it was over 3 bar measured at the furthest outside tap. The engineer remarked that the pressure was especially good.

Yes 3 bathrooms but realistically it's very unlikely more than 2 will be in use simultaneously.

I always think a good litmus test is to see what GCH engineers have in their own houses. My next door neighbour happens to be a GCH engineer and he has a Vaillant boiler with a Megaflow.

I haven't actually asked for a quote from him yet. Thought it might be risky getting work done by a neighbour in case things go wrong and turn sour etc.

 

[dcawkwell]

Take a look at the glow worm ultra power will do both jobs all in
the one box.

except it won't because if you go for the 100 ltr version after 3 mins it reverts to a combi with only 12.5 ltrs/min flow rate & that's in the summer, plus it's way way too dear & i'm guessing that would go in the airing cupboard which would mean re-routing the gas & flue, something the OP doesn't want to do

I won't consider the 100 litre version for a 3 bathroom installation.

170 litre version.

Reheat time at only 17 minutes.

 

[jonnydarcy]

In terms of tank size only upwards of 210 litre has been recommended, the vast majority suggesting 250.

It's a big house BTW, 2,400 sqft.

 

[dcawkwell]

In terms of tank size only upwards of 210 litre has been recommended, the vast majority suggesting 250.

It's a big house BTW, 2,400 sqft.

Tank size doesn't matter. It is how fast you can heat the water.

250 litre tank will reheat in 30 minutes approx so 500 litres an hour.

my 170 tank will reheat in 17 minutes approx so 600 litres an hour.



Not only that you can run a full bath empty the tank and the ultra power
will still keeep supply hot water indefinitely non stop.
The tank system will need reheats inbetween.

 

[ALEC1]

its not fair to say that every installers is influenced by points. and freebies I install viessmann vitodens 200s (with weather compensation) because it is the controls force the boiler to provide a decent temperature, be efficient and reliable but them and my suppliers leave a lot to be desired in terms of service to installers...

I have no other interest other than getting the "best" to my customers..

if you are going to install a new boiler and unvented do your self a favour and use a cylinder sensor do enable you to probram the hot water temperature to the degree, and get proprietary controls that enable the heating to be compensated...indoor or outdoor.

Such an approach minimises fuel consumption, enhances reliability and give you a noticeably improved heating system..

 

[ALEC1]

the remeha/ariston combination is fit for purpose... a little bit better if you use a twin coil cylinder enabling you to retro fit solar later, or plumb the two coils ins series to enable you to get a quicker reheat and enhance boiler efficiency...