Carrier 50KQL-1PD manual Guide specifications cont

Guide specifications (cont)

2.Piping:

a.Copper tubes with a 5/8-in. OD dimension shall be provided on the supply and return water connections for the purpose of forming a sweat connection to field-supplied distribution piping.

b.Optional threaded connections: A 1/2-in. male or female pipe threaded fitting shall be factory mounted on the supply and return water connections.

3.Unit Controls:

Safety devices on all units shall include low- pressure sensor or loss-of-charge switch, high- pressure switch, low water temperature sensor, and condensate overflow switch.

4.The standard Complete C electronic control system shall interface with the unit mounted or remote heat pump (Y,O) wall thermostat (mechanical or electronic). The control system shall have the following features:

a.50 va transformer.

b.Anti-short cycle time delay on compressor operation; time delay shall be 5 minutes minimum.

c.Random start on power-up.

d.Low voltage protection.

e.High voltage protection.

f.Condensate overflow shutdown.

g.Unit shutdown on low refrigerant pressures.

h.Unit shutdown on high or low water temper- ature (selectable for antifreeze solutions).

i.Option to reset unit at thermostat or discon- nect. Fault type shall be retained in memory if reset at thermostat.

j.Automatic intelligent reset. Unit shall auto- matically restart 5 minutes after shutdown if the fault has cleared. Should a fault occur 3 times sequentially, then lockout will occur.

k.Ability to defeat time delays for servicing.

l.Light-emitting diode (LED) to indicate high pressure, low pressure, improper voltage, water coil freeze protection, air coil freeze protection, condensate overflow, and con- trol status.

m.Unit Performance Monitor to indicate ineffi- cient operating conditions prior to unit lockout.

n.Remote fault type indication at thermostat.

o.Single harness connection for all safety devices.

p.Selectable 24-v or pilot duty dry contact alarm output.

q.24-v output to cycle a motorized water valve with compressor contactor.

r. The control box components shall be easily accessible with a swing out control compartment.

s. Standard unit-mounted MCO (manual changeover) thermostat operating controls shall consist of temperature setting dial knob, push button switches for Stop, Fan only, Hi Cool, Lo Cool, Hi Heat, Lo Heat. Unit-mounted thermostats shall have a remote sensor for sensing the return-air temperature.

5.The optional Deluxe D electronic control shall have all the features of the Complete C control, with the following additional features:

a.75 va transformer.

b.A removable thermostat connector.

c.Random start on return from night setback.

d.Minimized reversing value operation for extended life and quiet operation.

e.Night setback control from low temperature thermostat, with 2-hour override initiated by a momentary signal from the thermostat.

f.Dry contact night setback output for digital night setback thermostats.

g.Ability to work with heat/cool (Y, W) thermostats.

h.Ability to work with heat pump thermostats using O or B reversing valve control.

i.Single grounded wire to initiate night set- back or emergency shutdown.

j.Boilerless system control can switch auto- matically to electric heat at low loop water temperature.

k.Control board shall allow up to 3 units to be operated from one thermostat without any auxiliary controls.

l.A relay to operate an external damper. The control to be such that the damper will not open until 30 minutes after the unit comes back from Unoccupied mode.

m.Fan speed selection at thermostat.

n.A relay to restart a central pump or control a 24-v motorized water valve.

o.Intelligent fan speed selection based upon thermostat demand and/or dehumidistat signal.

6.Carrier PremierLink™ Controller:

This control will function with CCN (Carrier Comfort Network) and ComfortVIEW™ software. It shall also be compatible with ComfortLink™ controllers. It shall be ASHRAE 62-99 compliant and Internet ready. It shall accept a CO2 sensor in the conditioned space and be Demand Control Ventilation (DCV) ready. The communication rate must be 38.4K or faster.

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