Choosing a Conventional Condensing Boiler....

[stulew]

Hello Gents...
I have to install a new boiler for a conventional system and to be honest I am at a loss as to which one to recommend to my customer.
I have installed a few Non Condensing Combi Boilers and have tended to stick with Worc/Bosch and Baxi but this is going to be my first Condensing model. Have you got any advice as to which model to choose for ease of install (and reliability???) I am swayed towards Worcester but do not know which model. The system requires a minimum 60,000 BTU but I thought as the house in question is undergoing a small bit of renovation I will leave some room for any expansion work in the next few years, so a 80,000 BTU would be my choice.
Your help is appreciated as usual...

 

[PEDANTICVINDICTIVEMAN]

Always been a Worcester man myself until condensing compulsory, now gone onto fitting Ideal icos/isar at present due to Greenstars being overly unecessarily complicated, starting my third one on Wednesday, one I fitted week before last went in nicely in a cupboard and looked straightforward to service, my own 3 year old Isar looks ok on it's second service I did last week except for the hot water temp knob fell off, anyone else had this happen ?
Going to fit Honeywell RF CM67 for heating control and 24 hour timer for HW with a Y plan setup for tommorows job.
Dont bother with Glowworm as they want 50p per min to talk to tech line, robbing gits, wont get it from me out of principle.

 

[stulew]

Thanks for the reply Perdantic. What is the difference between the Isar and the Icos? I have had a look at the icos and read through the installation manual online and it does look simple enough even for someone like me that does not fit a load of boilers.Is it preferable to run the condensate into the sink waste or would I be better running it out into the outside drain ? I know that the end of the condensate drain pipe does have to terminate below ground level and has to be insulated against freezing, so if I do use the sink waste does this still apply? and finally are there any Water Regs regarding where the consensate enters the sink waste.
Thanks For Your continued help.

 

[kevplumb]

What is the difference between the Isar and the Icos?

one is a combi the other a system boiler

 

[keego]

Try the Ideal Classic HE dead easy to fit & not bad as far reliability goes.

 

[PEDANTICVINDICTIVEMAN]

The Icos I fitted last week went in the cupboard lovely and worked a treat, I fitted the condensate pipe onto the washing machine nipple on the sink trap under the sink, should be ok as far as I know as the Icos/Isar have an inbuilt trap on the boiler, you have to pour a cup of water into the flue on the boiler before fitting the flue pipe, the one I fitted today went on the wall easy peasy, I am running the condensate pipe along the outside wall and will insulate it, I like the simple flue fitting and straighforward wiring arrangment, no pump overun crap to deal with either, hopefully have it running tommorow, one thing which does worry me is that on both boilers the nut on the gas valve outlet was barely tight !!!! ,good job I check.
The next one I am doing I wil have to fit a soakaway for the drain, anyone had any experience with soakaways for condensers ????

 

[silverback]

Yes PV Man I have used the soakaway with a condensing boiler, Mc Alpine make one very simple to install will accept overflow pipe or 32mm pipe

 

[Slugbabydotcom]

If you want to make a decision with energy efficiency as part of the equation try here >> http://www.boilers.org.uk/
Then click the >> View the Boiler Efficiency Database button

Since 1st April you are now supposed to use this for calculation of boiler size >>http://www.sedbuk.com/whole_house.htm

 

[silverback]

Slugbabydotcom

I'm afraid you have been misinformed, you do not have to use the whole house method for sizing the boiler, this is only used for replacing a boiler in an existing system, it is to save the installer time, it gives an overall heatloss for the house dependent on the type, location etc,etc, this to because there is no guarantee that the original boiler was sized correctly.

If you are replacing the whole system, or fitting a completely new system you would carry out the heatloss calculations as before to determine the radiator outputs and size of boiler required

 

[Slugbabydotcom]

I am not so sure that I have been misinformed here. I actually just got back from doing an energy efficiency course and admit I may have been a little 'full of it' .
I should however have explained that it was a quick method and minimum legal requirement and there is nothing wrong with being more precise as you suggest even though even the best heat loss calculations were never regarded as a precise art
At the URL I gave it does actually state "Where the dwelling is untypical, then a more detailed procedure should be used."
To focus on the question posted, which concerned boiler sizing and not entirely related to radiator outputs, which have a margin for error; the answer lies in getting a range rated boiler that will work between any current and projected requirement and adjusting it accordingly.

 

[stulew]

Thanks Gents... I will take your advice and try the Ideal. I will let you know how I get on. So as far as you are aware it is OK to run the condensate pipe into the washing machine outlet on a sink trap.The consensate is acidic from what I remember does this still mean it's OK to run it this simple way. I have to admit it would make life easier if this can be done.

 

[Slugbabydotcom]

So as far as you are aware it is OK to run the condensate pipe into the washing machine outlet on a sink trap

Should be ok so long as the connection isnt smaller than ¾ pipe and there is no metal pipework further down the line. If you connect after the trap and the is no built in trap on the boiler; [which there usually is], you must fit one

 

[silverback]

PVMAN the details of the McAlpine soakaway the code is SOAK1GR, this is McAlpines code, Plumbcenter, Plumbase and most other merchants keep them in stock its measurements are 110mm diameter x 300mm deep, you need lime stone chippings for the soakaway to pour in around the outer of the soakaway and to pour inside, all you need is lime chippings from Build Center, I think they are chippings used for roofing or gardens, about £5 per bag, one bag will do about 10 soakaways, just ask for limestone chippings, don't do what I did and ask for limestone chippings for a condense soakaway, confuses the hell out of them, I was sent from pillar to post trying to get a bag and ended up back at the first place I went to.

 

[PEDANTICVINDICTIVEMAN]

Thanks for your replies, will be fitting my first soakaway soon by the looks of things.

 

[stulew]

And a Big Thanks from me as well......