help open vent to sealed system

[proper-bo]

hi, i have an open vent heat only system and the boiler is ready for a change,so was think about a sealed system,is this a big job,

1, do you have to change the hot water tank
2, what do you do with the pump in the airing cupboard
3, does it still need the 3 port vavle
4, will it need overflow capping off to header tank

thanks for your help

 

[crockett]

If you're asking, and I don't mean this disrespectfully, then it's not a job I would advise you to undertake. There is a fair amount of alteration to do, and depending on what sealed system you will get installed, you will need someone with an unvented ticket, as well as CORGI or Oftec as well

 

[proper-bo]

im not doing it myself

just trying to get my head around what needs doing so i dont get to confused when mr corgi comes round for the quote,if i need a new hot water tank,i will prob just have a boiler swap

 

[crockett]

If you're getting a combi fitted, then mostly it'll be a strip out of certain things, the cylinder being one of them, and f & e tank another. If you're having a sealed system, then you will be having an unvented cylinder fitted, which is more expensive, but I prefer. It is entirely dependent on how much money you're parting with

 

[LUNAT]

HI


fitting a sealed system is not straight forward.

1.yes
2.pump can fitted externally or can be bought as one (inside the boiler)
3.one three port or 2 two port valves
4.header tank will not be required

 

[proper-bo]

are open vent systems a thing of the past now, i known theres not many heat only boilers out there,they all seam to be combis and sealed,i dont want to pay a load of money for a old system type

a new boiler £600-700
a new tank £400-500
flue + bits £150-200
labour £???? what do you reckon 2 days


anybody got the number of a good coal man

 

[crockett]

Just do as most people do, get at least 3 quotes ( yes they WILL all be different, but thats the subjectiveness of plumbing ) and ask friends and family for recommendations.

Pricing, labour-wise, will depend on the plumber, and material cost will depend on brand and quality.

 

[Softus]

Just do as most people do, get at least 3 quotes

That's the way to guarantee that you waste the time of at least two of the businesses that you ask to provide a quotation.

The more people who do that the higher that prices become.

I guess the people who do it are the same ones who make fraudulent insurance claims, who are unable to work out that everyone's premiums pay not only for the amount paid out but for the cost of the administration in doing it. Pratts.

 

[londonboy123]

a lot of people still have conventional boilers/open vented systems. everyone i know, bar 1 person does!! if you want a sealed system the f & e will go (an expansion vessel will either be inside the boiler or external depending on type and what you want).

i have heard unvented cylinders are very good, expensive, but give very very good hot water pressures.

combis i have heard good and bad about. apparantly they are getting better but the hot water flow rate is often poor (especially if living in a busy household)!! and if the hot water is on for long periods, the heating can cool down and not a good idea in winter times!!

 

[BigBurner]

a lot of people still have conventional boilers/open vented systems. everyone i know, bar 1 person does!! if you want a sealed system the f & e will go (an expansion vessel will either be inside the boiler or external depending on type and what you want).

i have heard unvented cylinders are very good, expensive, but give very very good hot water pressures.

combis i have heard good and bad about. apparantly they are getting better but the hot water flow rate is often poor (especially if living in a busy household)!! and if the hot water is on for long periods, the heating can cool down and not a good idea in winter times!!

You have to consider that an unvented cylinder requires a yearly service charge. Heat bank thermal stores do not. They also offer far more than just a cylinder, being small commercial CH and DHW system in a domestic package.

There are lots of high flow combis around which are highly cost effective.

 

[simond]

There are lots of open vent high efficiency boilers out there, such as;

Viessmann 100 Compact, Broag Avanta 18v, Buderus 600R, Worcester Bosch Ri series, and Vaillant 400 series (in my order of preference).

There are few advantages in converting to a sealed system if your radiators are working fine now. Have you considered keeping the system opn vented?

 

[IJWS15]

Am I missing something here.

As I understand the systems just because you switch to a pressurised boiler you DO NOT have to switch to a pressurised hot water tank. The only item of the tank that sees the higher pressure is the coil and that should stand it with no problem. Tell me if I am wrong - we had one two houses ago.

I don't like pressurised boilers because a minor leak - one so small that the water lost evaporates in winter due to the hot pipes near it, can cause loss of pressure and loss of heating. It is not pleasant getting up at 0600 to a cold house in January when you have to go to work and SWMBO is complaining that there is no hot water and the house is cold. Open vented systems do not have this problem.

Never had a mains pressure hot water tank but the thought of annual service charges is putting me off!