Question

A heating system supplies 20 gpm of hot water at 200°F to a base board fin-tube radiation for a heating load of 92.000 Btu/hr. What is the exit temperature of the hot water?

Answer 1

The exit temperature of hot water =200.005°F

Step-by-step explanation:

Given that

Volume flow rate of water = 20 gpm ⇒

Volume flow rate of water =
`0.00126(m^3)/(s)`

inlet temperature of water = 200°F

Heating load = 92.000 Btu/hr ⇒ Heating load= 0.0269 KW

We know that mass flow rate is given as

`\dot{m}=\rho Q`

So mass flow rate of water = 1000 x 0.00126 Kg/s

mass flow rate of water= 1.26 Kg/s

Now by balancing heat

Heating load =
`\dot{m}C_p\Delta T`

`0.0269=1.26* 4.178(T_o-200)`

`T_o`=200.005°F

So the exit temperature of hot water =200.005°F