Rad sizing calculator

[e/bourneplumber]

Hi, I have to size a lot of radiators for a big detached house set in the countryside.
im looking for the best rad sizing calculator and wanted your opinion on what is the best / easiest to use.
thanks in advance

 

[SimonG]

cubic feet of room multiplied by room multiplier gives you btu's. Very rough and ready, but rarely far off the money.

 

[kris]

If you have a smart phone or android then theres an app called mr combi radiator calculator, very good app, i use it all the time and accurate,

 

[e/bourneplumber]

Thanks, I need something where I can email the client my working out as he is a commercial surveyor and likes to know how you get to every decision. I'm looking for a good computer program, I don't mind paying for it as I will use it any way, rather than use an online freebie.

 

[happyflyer]

E/B


You should use a excel spreadsheet with all the 'U' values for that property, do it proper none of this rule of thumb,
and you need to use proper ACR, old houses a draughty places oh and before ermi jumps in what about insulation.

If you set up a spreadsheet you can use it over and over again just tweaking the "U" values for different properties
also at the end of the data divide the total heal loss by the floor area or the volume and it gives you and idea if these
rule of thumbs are anywhere near, sometime they are, and sometime not!

Good Luck

 

[SimonG]

xl it is then.

 

[happyflyer]

The real trade software is Hevacomp all bells and whistles, it cost £1000s I have never seen a domestic one but there must be one, it will still
use a database or spreadsheet in there somewhere, you could write a MS access database but the spreadsheet is much easier.

 

[jonnyswamp]

Pace out every room, if the rooms are under 4 paces by 4 paces square chuck a 4ft single in, if they are bigger use a 4ft double........simple

Always seemed to work for my old boss in the eighties

 

[happyflyer]

That's why there is no gas in the North Sea, along with no insulation...:hand:

 

[Ermintrude]

Plus one for the bald gits suggestion.

 

[newcastle phill]

Spreadsheets are great. But who bothers with PC's any more..
They are so yesterday lol

 

[Chalked]

Use the rad sizing app on a room, and lets say it works out to 2800 btu (sorry no watts in this example) . The red needs to be a 450mm high, so you pick a 450 x 600k1 @ 2807 btu.

you then buy an expensive program that works out every loos and gain including farts! This after an hour of inputting data says you need 2674 btu's. so what do you do? Bang in a 450x 600 k1!

 

[Ermintrude]

Spreadsheets are great. But who bothers with PC's any more..
They are so yesterday lol

Set it up on google docs as a spreadsheet. Access and mod it from you phone.

 

[newcastle phill]

Have you got some sort of correction factor built in for the return temp for condensing boilers dew point as rads need to be sized larger to take account of lower return temps to keep em in condensing range.. or do you just go off rad manufacturers correction delta

 

[newcastle phill]

Thats one thing the apps dont seem tontake account ov