I hate asking the question, but here goes... it's about SIZE

[funkydiver]

I've read the stickies, and had a ponder... but coming up with a blank.

So far as sizing a combi boiler is concerned, "forget the rads, think of hot water demand" is messing with my noodle!

I'm looking at changing a 30 year old traditional boiler (and sacking the chimp that feeds it!)

It's a traditional cold store in loft, hot water tank for delivery, burn 1/4 of the daily output of the north sea gas field to heat the house setup.

The house is big, really... it's BIG. 14 heated rooms in total. Most currently have 2 radiators in them apart from the smaller rooms.

That said, there's only really 2 bathrooms of interest, and will be a hot water shower, and one kitchen. There are hand wash sinks dotted about, but nothing to cause any sleep loss over.

At any one time I'd envisage one bath being run, the kitchen sink and a dishwasher. Would prefer to have the flexibility of adding the shower to the mix if possible.

Am I looking at a small commercial / high capacity boiler (e.g Worcester-Bosch 54), or is a circa 40 kW boiler gonna cut it?

In the long run, we're going to be changing some of hte radiators to a more traditional style of rad, but again, try to keep the kW output matched with whats there at the moment. So take 2 rads out of the bedroom and put one back in.

 

[Dan Robinson]

Forget having a combi, unless you use it to run a shower and maybe the utilities.

 

[Agile]

I don't understand what you are hoping to achieve.

Your house probably does not need more than 28 kW maximum and with a good sized hot tank you can provide most of the water flow that you need either from the mains supply or from a storage tank and pressure pump.

Tony

 

[Dan Robinson]

Can't be that big a house with 14 rooms. 5 or 6 bed tops?

 

[funkydiver]

7 bedrooms, 4 reception rooms... and yes it is that big.

What am I trying to achieve? Err... heat and hot water, lol.

The house itself was up until recently a residential home (with an extension that has now been removed from the equation) and has a system boiler with mahoosive tank in place that made enough hot water for 6 baths in an evening, along with feeding an industrial washing machine, dish washer, 3 sinks in the kitchen... you get the picture?

We've taken the house back, sold the extension as a seperate bungalow and myself and family are moving in.

Soooo... the behemoth heating system that pretty much ran 24 hours a day, and is about 15-20 years old needs to go the journey. It's pretty much buggered now anyway, and although gas safe, our previous gas fitter / repair man / inspector(who has unfortunately passed on) was in process last January of sourcing a replacement if the place was to remain as a home. It's not.

Think I outline my requirement as best I can above. There's 6 of us in the family and 2 hangers ona hanger on that visits frequently...

At present it's pretty much uninsulated, or may as well not be, still had a lot of the period stained glass windows, all of which will be dealt with over time.

Short game is we need to move in, in 3 weeks time. End game is that it'll be a nice family home.

Hope that goes some way of explaining it.

 

[funkydiver]

Oh, the 14 rooms doesn't include the utility rooms / storage rooms. I only included the day to day living rooms.

 

[Agile]

Just counted mine and that's 14 too if you include hall and landing as they are heated.

 

[funkydiver]

My current house is 13 rooms... and physically it's about 1/4 of the size on the whole.

My mates bungalow floor plan fits in ONE of the rooms. Seriously, it's a big house.

I'll try get some proper measurements tomorrow if I get chance after work.

EDIT : Internal floor space is 300 sq m. Ceiling heights are Victorian... so about 12 ft... not sure what that is in new money.

 

[Dan Robinson]

You need to do proper heat loss calcs then. Its not worth screwing it up by guessing.

As i mentioned. A good trick for this type of project is to get a decent sized combi in and use the combi side to run the kitchen, utility cloakrooms and maybe a shower.

Then fit a cylinder with proper controls and zoning.


Look at the Intergas HRE 40

or the Atag Q51C if you reeeeallllllyyy need that heat capacity.

 

[SilentDancer]

Do not get a combi to heat a large house with multiple bathrooms it will only lead to disappointment when there is not enough hot water in the winter.

 

[Agile]

But before any decision is made you need to know the dynamic flow rate of the mains water supply.

Tony

 

[Dean744PiN5]

And don't forget a cpmbi can't do both at the same time so if 6 of you are using hot water in the morning the heating is going to be off for a long time.

 

[winchangoonygog]

Good size system boiler for your heating needs and an unvented hot water cylinder will give you hot water everywhere at mains pressure.

 

[Dan Robinson]

Do not get a combi to heat a large house with multiple bathrooms it will only lead to disappointment when there is not enough hot water in the winter.

Take it you didn't read my previous posts then?

 

[winchangoonygog]

Take it you didn't read my previous posts then?

Why ? does he have to pay homage or summat? Who are you? Your idea to install a combi was ridiculous.