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W.Miller
22-09-2008, 01:22 PM
Ground floor

Living room = 4m x 3.8m x 3m
Kitchen = 2.9m x2.1m x 3m
Dining room = 2.9m x 2.8m x 3m
Toilet = 1.5m x 1.5m x 3m
Hall = 3.5m x 1.3m x 3m

First floor

Bedroom1 = 3.1m x 2.8m x 2.9m
Bedroom2 = 3.1m x 2.5m x 2.9m
Bedroom3 = 2.5m x 2.4m x 2.9m
Bathroom = 2m x 2.1m x 2.9m
Upperhall = 2m x 1.9m x 2.9m

Can anyone help work out the heat load for this building I have been trying to do this but i keep coming ouy with different figures each time.

I calculated the whole area of the house assuming the outside temperature was 8c and the indoor 21c. So I did

Area = 22458 x (T1 - T2) 13 x U value of walls = 0.35, which gave me 102183.9. Around 29 kw. Is this correct

frank
22-09-2008, 08:26 PM
Dear W Miller

It says in your profile that you are an engineer? Surely, this heat gain calc should be a doddle to you.

However, to do a full heat gain calc, you have to look at each external wall individually, and take into consideration, glazing area, type of glazing, shading, orientation, sun azimuth for the time of year you are calculating, fabric construction details, insulation type, reflectance, building material colour, and then roof type, colour, construction, shading etc.

On top of all that, you need to look at degree days.

Simple init?

No wonder most 'engineers' just guess.

Good luck with the Btec.

Edit.

Just noticed that you are asking for heatloss calcs. Sorry chap, this is a Refrigeration forum

W.Miller
23-09-2008, 06:20 AM
I think I worked it out to be 8.5 kg. I wanted to add to my nvq level 2 in refrigeration. So i started doing an btec level 3 advanced dimploma in refrigeration, heating and air conditioning.

nevgee
23-09-2008, 11:22 AM
Whether you're calculating the load for heat loss (heating load) or heat gain (cooling loads) you should also allow for ventilation, be it natural or mechanical.

You're study notes and reference books should give you further indication of the whole requirement, and complexity, for you to complete the exercise.

study hard and enjoy!

W.Miller
02-10-2009, 12:11 AM
The actual answer to this is around 8kw of the top of my head. I finally worked out how to do the sums correctly. This course has taught me alot and is a good addition to my nvq2. I'm glad I done it.