New boiler- some facts

boiler_man

Hi all

After getting some great advice on other topics, and reading some questions within these threads, thought I would try to help with a few points.

April 2005 will see the introduction of changes to Part L of the building regulations. This relates to a government white paper of Jan 03 "Our energy future, Creating a low Carbon Economy"- The effect of this will be 80% plus of boiler installations will have to be SEDBUK band A or B or what is refereed to as High efficiency or condensing. (SEDBUK = Seasonal Efficiency of Domestic Boilers in the UK). The SEDBUK C or D installations will be allowed under a set of exemptions that have not yet been decided. (Does not apply to Scotland)

Condensing boilers work by using more of the heat contained within the flue gases instead of wasting it to outside. These type of boilers are only slightly more complicated than standard boilers, but care needs to be taken with the siting the flue due to "pluming" - steam within the flue gases being more visible as it contains less heat.

Prices of Condensing boilers have never been so cheap and now compare well to mid to high price range standard boilers. This is due to energy supplier funding of schemes to promote energy efficiency. ( this funding will finish as they become compulsory.)

Standard efficiency boilers fitted before April 05 will comply to all the regulations, and generally manufacturers are bound to still supply parts upto 15 years after production ceases.

Keeping old boilers running whilst on the surface seems a good idea, can be a false economy. Consider a 20 year old boiler and typical system of this age may be as poor as 50% efficient, that could be wasting 40% of your heating gas bill.

Combination boilers - both standard and condensing heat the water instantaneously as it passes through the boiler. These will give a hot water flow rate of between 9.5 to 15 litres per minute, at a 35C-temperature rise. This is relative to the heat output of the boiler typically 24 to 35Kw, the larger the boiler the more hot water produced. Combi boilers are typically suited to small to medium size installations as even at 15 L/M this can struggle with 2 bathrooms. To see for yourself the hot water flow rate run a tap and adjust it until the water fills a 2 gallon / 10 litre bucket in 1 minute or 45 seconds for the 15 L/M. Combi's are an excellent choice in the correct application as they save space, are a cheaper installation, but are more complicated, have less of a life span and have no back up in the event of problems.


Hope this helps with some of the recent questions I have seen posted

MATH

Thnx for that. I've got a 25yr+ boiler situated in the garage heating 10rads. The hot water cylinder was replaced last year. Looking to replace the boiler in the near future what would you recomend I go for.

boiler_man

Its very difficult to give you sound advice with the amount of information given, and best advice is to call in a reputable Corgi registered installer. But some of the considerations would be

• Would you happy with the systems performance if just the boiler is upgraded? or would a combi be more suited to your house and life style
  Have you got a fully pumped system with adequate controls
  Boiler size and flue type
  Can the boiler be replaced in the current position and comply with current reg's

Sorry this is not more precise, but there is no one fits all answer

MATH

Tnx for trying. perfectly happy with the system, just need a more efficient and cheaper to run boiler plus given it's age I'm worried on cold night it's going to break down.

boiler_man

If your happy , then probably just go for a direct replacement. All boiler sold now are at least SEDBUK "D" rated and 78% efficient. As for manufacturer for a non combi boiler, best bet is one of the British manufactuers eg, Ideal, Potterton, Baxi Gloworm.

MATH

Cheers

fluffymuffin

thanks so much for this - we are getting central heating out in our house in the next month and the plumber is coming in a week to discuss the finer points! I had heard off a mate in the trade there was new info coming in re boilers but didnt understand what he was on about - much appreciated clarification.

Is there anything this website cannot tell me about! Fantastic!

MATH

You can pretty much run your whole life from here In fact for some of us this site is OUR LIFE ;D

crankup

We've been considering replacing the old Potterton in our house. A good friend of ours is an old Corgi-registered heating/plumbing engineer so I spent some time discussing it with him.

Note that there are different levels of Corgi registration. Ensure your person is registered to do gas fitting. Some rogues will be "economical with the truth" when they say they are Corgi Registered. That may be so, but only to do certain things that are not relevant to your needs.

Here's some rule-of-thumb advice that I have picked up.
1. Cheaper the boiler, dearer the spares.

2. Condenser boilers are generally untested for longevity at the moment. They are put onto the market and faults are then dealt with as they come back, which is when they revise the design.

3. Manufacturers are required to provide spares for at least 10 yrs. Generally though, many supply for 30yrs on some models so this shouldnt be a problem.

4. What you gain in efficiency, you'll spend on servicing.


Our old Potterton hasnt had any problems in the last 5 years, all but being a bit noisy.

Our Vaillant combi in our last house broke down twice in 5 years. A microswitch needed replacing both times (£5 switch each time, so not too harsh).


I havent decided to replace the Potterton as I need to consider a new flue for a combi. Thats the only thing stopping me. We might stick it out and let the Potterton run until we can get an idea which condensers work reliably.


Good thread though - anyone else with some feedback?

Gaz_Hammer

Just following on from what crankup has posted!

If you want to check out the validity of any Corgi registered engineer then you can do one of two things!

1. Contact Corgi direct on 0870 401 2300

2. Check them out at the corgi website https://www.corgi-group.com

You will need either their registration number (the one under the shield) or the card issue number which is printed and embossed on the card on the top right.

For quick reference, on the rear of the Corgi picture ID card will a be a list of the elements that they are deemed to be competent in and the expiry date of that competency.
It is a requirement of Corgi that any operative carries their card with them at all times whilst undertaking any working with gas, associated gas appliances or pipework.

Hope this helps
Gaz

MikeUK_3-2

Hi some help would be appreicated to help on choice fo new boiler.

Ok I need a combi boiler suitable for a 4 bed house, with 4 occupants, house has approx 11 rads, would require a decent hot flow.

What boiler do I need and where to buy?

I know I have a cheek but need advice ASAP as I have been informed my current set up is deadly (Baxi back boiler with no front fire)

Thanks

Mike