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Formula To Calculate Btu For Aircon?

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What is the formula to calculate required BTU for airconditioning?

I have a 4*5*2.8m bedroom, approx 60m3

I did build a double westwall and will insulate the ceiling with fiberglass, that should reduce electricity bill.

Thanks.

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I have been told a couple of times now by seperate aircon guys, multiply the area by 700.....so 60sqm x 700 = 42,000

Thats a big sucker ?? I just saw you said 60 cubic meters, so if the bedroom is 4m x 5m = 20sqm x 700 = 14000btu, thats more like it.

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hi ya i was a plumber in the uk i now its differant but sure same applies . when working out radiator btu requirements we used a thing called a meires calculator (like a little disc) which takes into accont room size structure of walls floors ect iam sure air con engineers use similar diffice as formula is very complex beat of luck

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Some of the variables include glass windows (and whether the glass is insulated), curtains, exposure to the south or west, whether areas outside the area to be cooled are also cooled, thickness of insulation, humidity conditions, etc.

I had a huge room with roughly 10 square meters of thin glass facing west, another 15 sq. mt. of glass facing north and east, two showers, etc. I decided not to buy 59,000 BTU of air con.

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That's the beauty of Japan.

Each house/apartment has floor plans and how many tatamis each room covers. In print and schemes.

Aircons have the stickers on them what they are capable to heat/cool.

Just faxed to the shop what I have and adequate hardware came in, their staff mounted it and all perfect. No tips, just their job.

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A/C load calculations are straightforward...do a google on ASHRAE or Carrier. However, thermal conductivities related to building materials, insulation are important. To illustrate, I installed a 2 ton split unit in my bedroom without ceiling insulation. During the hot months you could only feel it if you were standing directly in front. I wised up and installed 6" fiberglass blankets in the roof space with a hugely significant inside temperature difference due to the 'R' value of the insulation. Now I just use the A/C to sleep and can make do with just a fan during the day. Before I had to spend all day downstairs as the bedroom was a hotbox, even with the A/C.

Take the time to consider these little things and you will be amazed about the money you will save on A/C power costs...

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That's the beauty of Japan.

Each house/apartment has floor plans and how many tatamis each room covers. In print and schemes.

Aircons have the stickers on them what they are capable to heat/cool.

Just faxed to the shop what I have and adequate hardware came in, their staff mounted it and all perfect. No tips, just their job.

Do any of you know a comprehensive means to calculate requirements here in Thailand - based on the above it is difficult to calculate requirements.

Surely there is a ball park means to finding the requirements

BKC

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That's the beauty of Japan.

Each house/apartment has floor plans and how many tatamis each room covers. In print and schemes.

Aircons have the stickers on them what they are capable to heat/cool.

Just faxed to the shop what I have and adequate hardware came in, their staff mounted it and all perfect. No tips, just their job.

Do any of you know a comprehensive means to calculate requirements here in Thailand - based on the above it is difficult to calculate requirements.

Surely there is a ball park means to finding the requirements

BKC

The staff manning the aircon department in the stores should be able to tell you on the spot what you need.

Then, anyone can google it and find something like this:

As a guide to the cooling capacity required in British Thermal Units (BTU's), calculate the volume of your room ie length x width x height (in feet). As a general rule of thumb, each cubic foot of space requires 5 BTU's of cooling capacity, so you need to multiply the volume by 5.

In addition, you need to add in the heat gain from other sources. These include people (400 BTU's each if there are more than two in the room) as well as computers and photocopiers (400 BTU's each).

For example, a room 10ft x 20ft x 8ft = 1600 x 5 = 8000 BTU's. With three people in the room, add 1 x 400 = 8400 BTU's. Add three PC's, 3 x 400 = 9600 BTU's total.

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The staff manning the air-con department in the stores should be able to tell you on the spot what you need.

:o:D:D

you should consider the position of the room and the room widows as to the directions,

i.e. facing the heat from the sun, that make a lot of different to the a/c cooling capacity,

That's the beauty of Japan.

Each house/apartment has floor plans and how many tatamis each room covers. In print and schemes.

Aircons have the stickers on them what they are capable to heat/cool.

Just faxed to the shop what I have and adequate hardware came in, their staff mounted it and all perfect. No tips, just their job.

Do any of you know a comprehensive means to calculate requirements here in Thailand - based on the above it is difficult to calculate requirements.

Surely there is a ball park means to finding the requirements

BKC

The staff manning the aircon department in the stores should be able to tell you on the spot what you need.

Then, anyone can google it and find something like this:

As a guide to the cooling capacity required in British Thermal Units (BTU's), calculate the volume of your room ie length x width x height (in feet). As a general rule of thumb, each cubic foot of space requires 5 BTU's of cooling capacity, so you need to multiply the volume by 5.

In addition, you need to add in the heat gain from other sources. These include people (400 BTU's each if there are more than two in the room) as well as computers and photocopiers (400 BTU's each).

For example, a room 10ft x 20ft x 8ft = 1600 x 5 = 8000 BTU's. With three people in the room, add 1 x 400 = 8400 BTU's. Add three PC's, 3 x 400 = 9600 BTU's total.

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That general rule of thumb, 5 BTU per cubic foot: is that for Calgary, or Phuket?

I googled it, did not even read carefully what it says. It was an example out of thousand serch results.

The remote control for the aircon in here in the room has almost as many buttons as a TV remote.

Now, 2 are important: heating or cooling.

25C in the winter is heating. In the summer when it is 45C outside it's good cooling. A switch on the remote tells the unit whether maintain the temp by heating or by cooling.

The BTU sticker on the aircons did not say what they are worth in winter and what in summer. So I guess, they should be as good in Calgary as in Phuket.

Winter here can bring some snow or you can have 5-8C for months. Insummer it can stretch into 2-3 months of over 40C.

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Anyone know what the electric cost is for these units per hour, however it is calculated for the various sized untis etc.

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Anyone know what the electric cost is for these units per hour, however it is calculated for the various sized untis etc.

I just looked at the sticker on the bigger aircon that I have here. There are figures in kW, it's kanji what they are for, sorry, can't read it.

There are 8 of them, ranging from 0.62kW ph to 5.2kW per hour.

I guess, depends what you want them to do. The lowest one could be, the aircon is serving as a plain fan, just shuffling the air. The highest one (5.2kW) could be to maintain 15C or whatever while it is 45C outside.

Edit: there were more figures, the highest one is not 3.8, it is 5.2kW per hour.

So, the worst case scenario with this model of aircon would be (if you pay electricity directly, at 2.2B per unit) = 11.44 Baht per hour. More likely, half or near half that.

Then, if you use it under the haviest possible load, 10 hours per day, you get the picture: 3300B per month or so.

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"I guess, depends what you want them to do"

******

stop guessing, try to write more science fiction (as in your posting) and make some money with it.

:o

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"I guess, depends what you want them to do"

******

stop guessing, try to write more science fiction (as in your posting) and make some money with it.

:o

It's a science fiction for you? Appliances ?

Start with a toaster, look at it for a day, try to understand it.

If it is too complicated, go with a laddle.

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BANGKOK 28 July 2017 15:51
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