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H.2 heat losses through envelope, H.3 heating load on ventilation, H.4 heating load due to infi ltration – Retrotec USACE User Manual

Page 362: Where

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H2 ENERGY & PROCESS ASSESSMENT PROTOCOL

H.2 Heat Losses through Envelope

Q

loss

=

[k * A * (t

room

t

out

)]

where:

Q

loss

=

losses of heat through the building envelope, kW

k

=

overall heat transfer coeffi cient of the envelope element, W/m

2

* °C

A

=

area of the building element, m

2

t

room

=

indoor air temperature, °C

t

out

=

outdoor air or soil temperature, °C

H.3 Heating Load on Ventilation

Q

vent

=

* C

p

* Q

v

* (t

s

t

out

)

Q

HR

where:

Q

vent

= thermal load on ventilation, kW

= air density, kg/m

3

C

p

= heat capacity of air, kJ/(kg * °C)

q

vent

= ventilation airfl ow rate, m

3

/s

t

s

= supply air temperature, °C

t

out

= outdoor air or soil temperature, °C

Q

HR

= heat recovered from exhausted air by heat recovery equipment, kW

H.4 Heating Load Due to Infi ltration

Q

inf

=

* C

p

* q

inf

* (t

i

t

out

)

where:

Q

inf

= heat losses due to infi ltration, kW

= air density, kg/m

3

C

p

= heat capacity of air, kJ/(kg * °C)