SetpointManager:MixedAir Reference node name in Blow-through fan placement

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I am trying to setup a blow-through vav airhandler with hot and chilled water coils. In this case the Hot Water coil is the last object and the outlet node name of the coil coincides with the setpoint node of the air handler. For the setpointManager:MixedAir the reference node would then coincide with the setpoint node. This appears to be not acceptable from the error I am getting (shown below).

All Energyplus example files appear to use a draw-through fan arrangement and this problem gets eliminated there as the setpoint node would be the fan outlet node.

Is it possible to have a blow-though fan air handling unit and what should we use for the setpointManager:MixedAir reference node.

Here is my branch and setpointManager Inputs:

Branch,
ahu2 Main Branch,    !- Name
, !- Pressure Drop Curve Name
Fan:VariableVolume,  !- Component 1 Object Type
ahu2 Extract Fan, !- Component 1 Name
ahu2 Supply Side Inlet, !- Component 1 Inlet Node Name
ahu2 Extract Fan Air Outlet Node, !- Component 1 Outlet Node Name
AirLoopHVAC:OutdoorAirSystem, !- Component 2 Object Type
ahu2 Outdoor air system, !- Component 2 Name
ahu2 Extract Fan Air Outlet Node, !- Component 2 Inlet Node Name
ahu2 Mixed Air Outlet Node, !- Component 2 Outlet Node Name
Fan:VariableVolume, !- Component 3 Object Type
ahu2 Supply Fan, !- Component 3 Name
ahu2 Mixed Air Outlet Node, !- Component 3 Inlet Node Name
ahu2 Supply Fan Outlet Node, !- Component 3 Outlet Node Name
CoilSystem:Cooling:DX, !- Component 4 Object Type
ahu2 dx Cooling Coil, !- Component 4 Name
ahu2 Supply Fan Outlet Node, !- Component 4 Inlet Node Name
ahu2 Coil 1 outlet Node, !- Component 4 Outlet Node Name
Coil:Heating:Water, !- Component 5 Object Type
ahu2 hw Heating Coil, !- Component 5 Name
ahu2 Coil 1 outlet Node, !- Component 5 Inlet Node Name
ahu2 Supply Side Outlet Node; !- Component 5 Outlet Node Name

SetpointManager:Warmest,
ahu2 Setpoint Manager, !- Name
Temperature, !- Control Variable
ahu2, ! HVAC Air Loop Name
12.78, !- Minimum Setpoint Temperature {C}
15.56, !- Maximum Setpoint Temperature {C}
MaximumTemperature, !- Strategy
ahu2 Supply Side Outlet Node; !- Setpoint Node or NodeList Name

SetpointManager:MixedAir,
ahu2 hw Heating Coil Mixed Air Manager, !- Name
Temperature, !- Control Variable
ahu2 Supply Side Outlet Node, !- Reference Setpoint Node Name
ahu2 Mixed Air Outlet Node, !- Fan Inlet Node Name
ahu2 Supply Fan Outlet Node, !- Fan Outlet Node Name
ahu2 Supply Side Outlet Node; !- Setpoint Node or NodeList Name

Error

   ** Severe  ** GetSetPointManagerInputs: SetpointManager:MixedAir="AHU2 HW HEATING COIL MIXED AIR     MANAGER", reference node.
   **   ~~~   ** ..Reference Node is the same as the SetPoint Node
   **   ~~~   ** Reference Node Name="AHU2 SUPPLY SIDE OUTLET NODE".