Methods and apparatus for latent heat extraction

A moisture control system (900, 1100) for use with an associated four-pipe air conditioning system (100, 200) including an associated chilled water source conduit (162) delivering a cold working fluid (950, 1150) from an associated chilled water source (160), an associated chilled water return conduit (166) returning the cold working fluid (950, 1150) to an associated chilled water return (164), an associated hot water source conduit (282) delivering the warm working fluid (952, 1152) from an associated hot water source (260) to the reheat coil (970, 1170), an associated hot water return conduit (286) returning the warm working fluid (952, 1152) from the reheat coil (970, 1170) to an associated hot water return (284), the moisture control apparatus (900, 1100) comprising:

• an integrated air treatment coil (940, 1140) comprising:
• a housing (910, 1110) configured to receive a return air flow (920, 1120) into the housing and to exhaust the return air flow from the housing as a cooled supply air flow (930, 1130);
• a plurality of fins disposed in the housing;
• a cooling coil portion (940′, 1140′) mechanically and thermally coupled with the plurality of fins in the housing, the cooling coil portion (940′, 1140′) being in operative fluid communication with the associated chilled water source conduit (160), the cooling coil portion (940′, 1140′) receiving the working fluid (950, 1150) from the associated chilled water source (160) via the associated chilled water source conduit (162) and flowing the working fluid therethrough thereby absorbing thermal energy from the return air flow (920, 1120) as the cooled supply air flow (928, 1128);
• a precooling coil portion (940″, 1140″) in the return air flow (920, 1120) and mechanically and thermally coupled with the plurality of fins in the housing, the precooling coil portion (940″, 1140″) receiving a first portion (954, 1154) of the working fluid (950, 1150) and exchanging thermal energy between the return air flow (920, 1120) and the first portion (954, 1154) of the working fluid (950, 1150) flowing through the precooling coil portion (940″, 1140″), wherein an input of the precooling coil portion (940″, 1140″) is in fluid communication with an output port (166′) of the cooling coil portion (940′, 1140′);
• and
• a reheat coil portion (970, 1170) mechanically and thermally coupled with the plurality of fins in the housing where a warm working fluid (952, 1152) flowing through the reheat coil portion (970, 1170) adds thermal energy to the cooled supply air flow (928, 1128) as a reheated supply air flow (930, 1130),
• a wrap-around fluid conduit (964, 1164) in operative fluid communication with the associated chilled water return conduit (166), the precooling coil portion (940″, 1140″), the associated reheat coil (970, 1170), and the hot water return conduit (286), the wrap-around fluid conduit (964, 1164) containedly directing the first portion (954, 1154) of the cold working fluid (950, 1150) through a series arrangement of an input (166′) of the wrap-around fluid conduit (964, 1164), the precooling coil portion (940″, 1140″), and the associated reheat coil (970, 1170);
• and
• a regulator circuit (980, 1180) operatively coupled with the input (166′) of the wrap-around fluid conduit (964, 1164) and with the associated chilled water return conduit (166), the regulator circuit (980, 1180) metering the first portion (954, 1154) of the cold working fluid (950, 1150) from the associated chilled water return conduit (166) for communication of the first portion (954, 1154) of the cold working fluid (950, 1150) to the input (161′) of the wrap-around fluid conduit (964, 1164).