Calculate U-Value for Glazed Window with 3m^2 Area and 400W Thermal Transmission

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To calculate the U-value of a single glazed window with a 3m² area transmitting 400W at a 15°C temperature difference, the U-value can be derived from the formula U = Q / (A × ΔT). In this case, Q is the heat transfer (400W), A is the area (3m²), and ΔT is the temperature difference (15°C). The U-value is calculated as U = 400W / (3m² × 15°C), resulting in a U-value of approximately 8.89 W/m²K. The U-value measures the rate of heat transfer through a square meter of material for each degree of temperature difference. Understanding this calculation is essential for evaluating window insulation performance.
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A single glazed window of area 3m^2 transmits 400W when there is a temperature difference of 15C across the glass, What is the U-value of the glass??

Help me, how do i work this out?
 
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suf7 said:
A single glazed window of area 3m^2 transmits 400W when there is a temperature difference of 15C across the glass, What is the U-value of the glass??

Help me, how do i work this out?
What are the units of U value? What is the power per unit area that is transmitted by the glass? Can you work out the U value from that?

AM
 
Andrew Mason said:
What are the units of U value? What is the power per unit area that is transmitted by the glass? Can you work out the U value from that?

AM

No??...what equations do i need for them?
 
suf7 said:
No??...what equations do i need for them?
I think you can look this up as well as I can. U value measures the energy in watts flowing through a one m^2 area of glass surface having a temperature difference of one degree between the inside and outside. Work it out from that.

AM
 
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