Hvac systems having improved four-way valve reheat control

A heating, ventilating, and air conditioning system comprising:

• a plurality of conduits forming a closed network containing a working fluid;
• a condenser coil fluidly coupled to the plurality of conduits and forming a portion of the closed network, the condenser coil for cooling the working fluid;
• an evaporator coil fluidly coupled to the plurality of conduits and forming a portion of the closed network;
• wherein the evaporator coil is configured to cool an air flow to be conditioned and produce a first conditioned air flow;
• an expansion device fluidly coupled to the plurality of conduits and forming a portion of the closed network and positioned between the evaporator coil and the condenser with respect to the flow of the working fluid in the closed network, the expansion device for expanding the working fluid and cooling the evaporator coil;
• a compressor fluidly coupled to the plurality of conduits and forming a portion of the closed network and positioned downstream of the evaporator coil with respect to the flow of the working fluid in the closed network;
• a four-way reheat valve fluidly coupled to the plurality of conduits and forming a portion of the closed network and positioned between the compressor and the condenser with respect to the flow of the working fluid in the closed network;
• a reheat coil fluidly coupled to the plurality of conduits and forming a portion of the closed network, the reheat coil receiving the first conditioned air flow and selectively producing a second conditioned air flow, the reheat coil fluidly coupled with respect to the working fluid in the closed network to the four-way reheat valve;
• wherein the four-way reheat valve comprises:
• a valve body having a main valve chamber,
• a first conduit coupled to the valve body fluidly coupled to the compressor for receiving working fluid from the compressor,
• a second conduit coupled to the valve body and fluidly coupled to the condenser for discharging a working fluid at least partially to the condenser,
• a third conduit coupled to the valve body and fluidly coupled to a suction port of the compressor, the third conduit for fluidly coupling with the compressor,
• a fourth conduit coupled to the valve body and fluidly coupled to the reheat coil,
• a piston valve slide member disposed within the main valve chamber and slideable between a first position and a second position, wherein the first position, which is a cooling position, fluidly couples the first conduit and the second conduit and fluidly couples the third conduit and fourth conduit, and wherein the second position, which is a reheat position, fluidly couples the first conduit and the fourth conduit and fluidly couples the second conduit and the third conduit, and
• a pilot valve fluidly coupled by a first pilot conduit to the first conduit upstream of the valve body, the pilot valve fluidly coupled by a second pilot conduit to a portion of the valve chamber proximate a first end of the main valve chamber, the pilot valve fluidly coupled by a third pilot conduit to a second end of the main valve chamber, and the pilot valve fluidly coupled by a fourth pilot conduit to the third conduit downstream of the valve body;
• and
• an orifice coupled within the third conduit downstream of the valve body and upstream of a location where the fourth pilot conduit is coupled to the third conduit.