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mburns
17-07-2011, 05:22 AM
According to Boyles law the volume is inversely proportional to the pressure applied providing the temperature remains constant. So for example if a condensor coil were sized for a temp difference of 15k it would equate to a certain pressure. Now if i were to put in a larger coil the volume would increase and the pressure would drop causing a lower temperature difference say for example 5k. My question is applying this rule to the evaporator side of the system. If i we're to increase the size on the evap thys increasing the volume and decreasing the pressure? I've always been led to believe that a larger coil would cause lower evap temp difference thus a higher low side pressure but this seems to contradict the theory i've applied to the condensor?

helm_n
01-08-2011, 10:13 AM
bigger condenser, higher cost but will lower your condensing temperature, increase system efficiency.

on evaporator coil, bigger mean high evaporating temp, increase compressor cooling capacity. face area stick to 1.6 to 2.5 m.s face velocity.

Rahju
01-08-2011, 01:19 PM
The condenser capacity should match as
closely as possible the capacity of the compressor in the system, although
oversizing is preferable to undersizing if compressor efficiency
is to be maximized.

D.D.KORANNE
12-08-2011, 11:16 AM
Condenser size should be evaporator capacity + compressor motor kw rating . Also provide for pull down condition . Hence if you take condenser capacity equal to compressor , you will have problem of high condensing temp / pressure