Condensing boiler

lloydyboy

Was told by my plumber that Firebird boiler for house is too small. Recommended a condensing boiler. anyone got any experience of these. Also said it would cost around 2K.

Joey the lips

Your not providing enough information, Firebird do a condensing boiler. its new regulations that a condensing boiler has to be used but like a standard boiler it comes in different sizes.


By the way - Firebird is an excellent boiler and its a cork based company.

thekooman

we have a Firebird Condenser 120 in our new house; heats 30 rads but we have it zoned into 5 zones so not all would be on at the same time; depending on what zones need it.
the boiler is a miser on oil. would definitely recommend it. have heard from my plumber brother that they have increased in price by a couple of hundred since last year.

lloydyboy

Joey the lips wrote: »

Your not providing enough information, Firebird do a condensing boiler. its new regulations that a condensing boiler has to be used but like a standard boiler it comes in different sizes.


By the way - Firebird is an excellent boiler and its a cork based company.

My house was built in early 2007 probably just before the regs. Just flying thru the oil in winter current boiler is 90-120 btu was told I would need 150btu for the 2400 sq ft house i have.

Not slagging off firebird just wondering if people can recommend changing over to them.

Joey the lips

lloydyboy wrote: »

My house was built in early 2007 probably just before the regs. Just flying thru the oil in winter current boiler is 90-120 btu was told I would need 150btu for the 2400 sq ft house i have.

Not slagging off firebird just wondering if people can recommend changing over to them.

Thats perfect you need a 150 btu boiler. This is a big boiler. Gerkross is another boiler you can get its an irish boiler, good model and cheaper than a firebird. They do a condensing indoor and outdoor model as well. Firebird is a great boiler. great customer service!

PS: Thats why your flying through the oil. The boiler is working all out!

Borzoi

lloydyboy wrote: »

My house was built in early 2007 probably just before the regs. Just flying thru the oil in winter current boiler is 90-120 btu was told I would need 150btu for the 2400 sq ft house i have.

Not slagging off firebird just wondering if people can recommend changing over to them.

TBH if the system wasn't designed for a condensing boiler you won't get the efficiency benefits. They work with lower water temps, so need slightly larger rads. It will still work at the higher temp, just you don't get that extra efficiency

Joey the lips

Borzoi wrote: »

TBH if the system wasn't designed for a condensing boiler you won't get the efficiency benefits. They work with lower water temps, so need slightly larger rads. It will still work at the higher temp, just you don't get that extra efficiency

This is the first time I heard this and I am selling rads 10 years. I dont think this is the case and if it is not many plumbers are aware of it.

If you can relate me to articles I will read them!

De_man

Borzoi wrote: »

They work with lower water temps, so need slightly larger rads.

not true, let me find the info to show what is a condensing boiler & how
it actually works

De_man

De_man wrote: »

not true, let me find the info to show what is a condensing boiler & how
it actually works

found a link

http://en.wikipedia.org/wiki/Condensing_boiler

this'll explain how it works follow the links for further information

Borzoi

De_man wrote: »

not true, let me find the info to show what is a condensing boiler & how
it actually works

Not, not true

From the wiki:
Part of the efficiency drop is because the design and / or implementation of the rest of the heating system gives return temperatures at the boiler over 50°C, which prevents significant condensation in the heat exchanger.[3] Better education of both installers and owners could be expected to raise efficiency towards the reported laboratory values.

QED

Basically your using the secondary heat exchanger to raise the return water temperature, and so partly condense the water vapour in the flue gases. If the return water temperature is too high, this is not possible, so you don't get the extra efficiency. In order for the return temperature to be lower, and still have the same heat effect, you need larger surface areas (bigger rads)

Bit more info on condensing boilers http://www.condensingboiler.org.uk/, might help, Gary.

JamesM

Gerkros went into liquidation last year - have they come out again :D
If the house is only 2 years old, I would check with whoever drew up the heating plans and decided that the 90 / 120 boiler would suit. I am not an expert on house size and suitable boilers, but the 90 / 120 is a big boiler and should cope. You have a large house, and last winter was a cold one - most people used more oil than usual. I would not rush into anything that will cost you thousands.
Firebird and Grant are good Irish makes of boiler.
Jim.

Joey the lips

Jesus james I never heard that on gerkross. A brilliant boiler. I was just suggesting a cheaper alternative to firebird,

I agree grant is another good on, thanks for the info.

JamesM

Joey the lips wrote: »

Jesus james I never heard that on gerkross. A brilliant boiler. I was just suggesting a cheaper alternative to firebird,

I agree grant is another good on, thanks for the info.

Just out of interest, here it is:
————
THE HIGH COURT
RECORD NO. 2008 NO. 454 COS
IN THE MATTER OF
GERKROS BOILERS (TIPPERARY) LIMITED
(In Liquidation)
AND IN THE MATTER OF
THE COMPANIES ACTS 1963-2006
By an order of the High Court made in the above matter dated
the 24 November, 2008, it was ordered that Gerkros Boilers
(Tipperary) Limited having its registered office Donaskeigh,
County Tipperary be wound up by the Court and that Mr. Barry
Forrest of Forrest Lennon, 12 Whitefriars, Peter’s Row, Dublin
2 be appointed Official Liquidator of the said Company.
27 November, 2008.
MATHESON ORMSBY PRENTICE,
Solicitors for the Official Liquidator,
70 Sir John Rogerson’s Quay,
Dublin 2.
[

Joey the lips

Borzoi wrote: »

Not, not true

From the wiki:
Part of the efficiency drop is because the design and / or implementation of the rest of the heating system gives return temperatures at the boiler over 50°C, which prevents significant condensation in the heat exchanger.[3] Better education of both installers and owners could be expected to raise efficiency towards the reported laboratory values.

QED

Basically your using the secondary heat exchanger to raise the return water temperature, and so partly condense the water vapour in the flue gases. If the return water temperature is too high, this is not possible, so you don't get the extra efficiency. In order for the return temperature to be lower, and still have the same heat effect, you need larger surface areas (bigger rads)

Borzoi I think your still mis understanding this but i am going to chek it out. Engineers have been certif Single panel 500 x 400 rads and Double Panel 500 x 400 rads in Ensuites and bathrooms and this has not changed with the introduction of the condensing boiler.

Your condensing boiler review

A condensing boiler is a money saving modern boiler that incorporates an additional heat exchanger in order that the hot waste gases transfer a percentage of their inherent heat to pre warm the mains water to be heated. When running at a good efficiency, the water gases developed in the working process distills back into liquid form liberating the latent heat of vaporisation.

A fallout will be this liquid, known as condensate, often acidic, required to be piped away to a waste pipe or water drain. The boiler is required to be placed on a wall and the exhaust gases will rise through the flue. Hot water is initialy served by a little storage tank to enable quick hot water accessibility.

There is loads of information available on these I think you are getting the workings confused. There is no doubt in the industry that a condensing boiler is more efficient and larger rads are not needed. Rads are specified by there output and the size of the room.

I am not coming back at you to repute you but its important your under the opinion that condensing is the way to go. This will be a costly mistake if you advise otherwise. Boilers are rated by there output the boiler is calculated by adding up all the rad requirement giving 20000 btus on top for water and an extra 20000 btus for expansion of the system but builders sometimes dont allow for expansion as its not a legal requirement just a best practice.

Borzoi is correct, to get a condensing boiler to run at it's most efficient you would need to run the system below 55°C, this allows allows the heat transference from flue to system water and the system would have to be designed to run that way IE under floor heating, installing a condensing boiler on a system with rads and a cylinder will require a flow of 82°Cish, (return 62°C) this prevents heat transference to the system water in the secondary heat exchanger as the secondary heat exchanger is hotter than the flue gas running threw it, the boiler will run most efficiently on start up, in saying that condensing boiler are still more efficient than traditional boilers and with gas there is no choice, Gary.

Borzoi

Joey the lips wrote: »

There is loads of information available on these I think you are getting the workings confused. There is no doubt in the industry that a condensing boiler is more efficient and larger rads are not needed. Rads are specified by there output and the size of the room.

I am not coming back at you to repute you but its important your under the opinion that condensing is the way to go. This will be a costly mistake if you advise otherwise. Boilers are rated by there output the boiler is calculated by adding up all the rad requirement giving 20000 btus on top for water and an extra 20000 btus for expansion of the system but builders sometimes dont allow for expansion as its not a legal requirement just a best practice.

To take the part in bold first:
Every radiator manufacturer gives a nominal output and has a data sheet with correction factors for different water & room temperatures. I've found the MHS Radiators one online so I'll use it.

Say you have a boiler producing water at 80C and we need 21C in the room. Imagine we've a 2kW nominal value radiator.

If the return water temperature is 65C, then the average temperature difference form the water to the room is (80+65/2)-21 = 51.5K so using the correction factor of 1.04 (approx) the actual duty of the rad is 2000 * 1.04 =2080W

Now, say we substitute in our condensing boiler, to get that extra efficiency we need a lower return water temperature say 52C, everything else the same. TD is (80+52/2)-21 = 45K, correction factor from catalogue 0.872, actual radiator output 2000 * .872 = 1744W

It's 20% undersized:eek:

So IMO there's no point in shelling out for an expensive condensing boiler if you can't get the benefits, and you can't unless the WHOLE SYSTEM has been properly designed to suit.

BTW when I first started doing heating loads and sizing rad systems 20 years ago the first thing we did was CALCULATE the room heat load, not just take a room size! Of course then we added 20% for Monday morning cold starts :rolleyes::D

Joey the lips

I am speechless but I am going to check this out. It makes you worry about the size of rads specified in houses.

Your talking about a 4-5% drop in efficiency, Borzoi is absolutely right in what he has written and i would take it in to account for new builds and brand new installations but for boiler replacements i would be happy to fit a modern condensing boiler to a old system, for oil thats still 93% with a Grant vortex and with gas i can gain from the extras that come with most modern gas boilers like outdoor stats and better logic on the pcb's that monitor how the heat is being used and adapt to the conditions of the individual house so as not to waste heat, i find i can't get installers to read the manufactures instructions in respect of getting the basics right so to stipulate a lower return temperature although on paper a simple task would end in tears as the decent plumbers tend to be out numbered by the fruit loops with a spanner, Gary.

245

lloydyboy wrote: »

My house was built in early 2007 probably just before the regs. Just flying thru the oil in winter current boiler is 90-120 btu was told I would need 150btu for the 2400 sq ft house i have.

Not slagging off firebird just wondering if people can recommend changing over to them.

Your boiler may be 90-120 BTU but the nozzle in your burner may be too small so that the boiler is not giving maximum output. Also, you need to look at possible areas of heat loss as its not just a case of putting heat into the house but also keeping it there. I'm not saying that your boiler is suitable but that there are many factors to consider before replacing it - dividing the house into zones, thermostatic rad valves etc etc

It may even be possible that the burner wasn't properly commissioned to start with...

JIMMYBOND007

my advice to you is ask the man that gave you the quote is he an oftec engineer if hes not walk away from him!! do not take advice off a plumber,there not qualified to do the job unless there oftec ,a new boiler has to be commissioned by oftec lad so manufactors warrentee is not invailed,it will say this on all manufactors instruction manuallys ,this is why your boiler might be undersized because the person was not qualified to do the job!! oftec lad will fill out boiler sizing chart on exact measurement of the house,will check you have full boiler interlock system .and will give you a full analayser print out so you know how effience your system is. some of the [EMAIL="bulls@*t"]bulls@*t[/EMAIL] you here about a condensing boiler not been more effience is aload of **

noelcunningham

lloydyboy wrote: »

Was told by my plumber that Firebird boiler for house is too small. Recommended a condensing boiler. anyone got any experience of these. Also said it would cost around 2K.

Hi, I'm a plumber and price for a condensing boiler sounds about right if your present boiler is below 90/110k BTU it is too small. Would need further info to accurately assess how much it would cost and what would be most practical. If you want more information pm me and i can send you my contact details

Regards,
Noel

JamesM

JIMMYBOND007 wrote: »

ps: watch out for old school lads who tell you there full of expereince,there usally wrong:)

Also be wary of "new school lads" who did not make it in the house alarm business, so decided to do a quick course in heating, but have no experience

JIMMYBOND007

theres alot of lads with experience that need a quick course in heating to get up to standards james,im glad you liked my wind-up!!! maybe you could come work for me someday when i do make it!!but you probable wont want to since you'v made it already james€€€€€€€€:D:D:D

JIMMYBOND007

JamesM wrote: »

I am afraid that you are more like M than 007. You seem to have a lot of knowledge about oil and gas burners, but I doubt that you have ever got your hands dirty.
Out in the real world, certainly the guys who service gas seem to be qualified, but the oil guys I know are the "old school" and do not have any qualifications.(although some are plumbers). Many of them have over 30 years experience


remember this james:)my answer to "many of them have 30 years experience "is ignorence is no excuse james as i was tought,no point and having the experince and not been qualified to do the job!will that work in court if something goes wrong?its not really a quick course idir,when i went back to do boilers i was in for 6months;)its not that i didnt make it in alarms idir ,i didnt even try to make it if you read the tread :cool:
THIS IS to all oldschool lads"RESPECT";)

CL7

I wish people would stop feeding this troll and answer my Condensing boiler thread.

obwalsh

installed a condensing boiler recently, it is cutting off periodically.
When running continuous black smoke is coming from flue.
Help needed.

thekooman

i know our Firebird condensing boiler starts cutting on and off every few months. its because the sensor at the front is covered in soot. i do take off the front red cover, pull out the black sensor and clean the top of it with a tissue... might help ya.... not sure why there is smoke though. best to call a plumber.