Carrier Weathermaster 48P2030-100, Controls, Start-Up, Operation, Service, And Troubleshooting

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Hydronic Heating Control Derivative Gain (HW.D)
This configuration is the derivative term for the PID which
runs in the HVAC mode LOW HEAT.
Hydronic Heating Control Run Time Rate (HW.TM)
This configuration is the PID run time rate which runs in the
HVAC mode LOW HEAT.
Hydronic Heating Logic
If the HVAC mode is LOW HEAT:
• The control will command the supply fan on
• The control will modulate the hot water coil actuator to the
heating control point ( Run Status

VIEW

HT.C.P ).
The heating control point for hydronic heat is the heating
supply air set point ( Setpoints

SA.HT ).
If the HVAC mode is HIGH HEAT:
• The control will command the supply fan on
• The control will command the hot water coil actuator to
100%.
Hydronic Heating PID Process
If the HVAC mode is LOW HEAT, then the hydronic heating
actuator will modulate to the heating control point ( Run Sta-
tus

VIEW

HT.C.P ). Control is performed with a generic
PID loop where:
Error = Heating Control Point (
HT.C.P ) – Leaving Air Tem-
perature (LAT)
The PID terms are calculated as follows:
P = K *
HW.P * error
I = K * HW.I * error + “I” last time through
D = K * HW.D * (error – error last time through)
Where K = HW.TM /60 to normalize the effect of changing the
run time rate.
NOTE: The PID values should be not be modified without ap-
proval from Carrier.
Freeze Status Switch Logic (Inputs

GEN.I

FRZ.S)
If the freezestat input (FRZ) alarms, indicating that the coil is
freezing, normal heat control is overridden and the following
actions will be taken:
1. Command the hot water coil actuator to 100%.
2. Command the economizer damper to 0%.
3. Command the supply fan on.
Configuring Hydronic Heat to Communicate Via Actuator
Serial Number
Every actuator used in the P Series control system has its own
unique serial number. The rooftop control uses this serial num-
ber to communicate with the actuator. These serial numbers are
programmed at the factory and should not need changing.
Should field replacement of an actuator become necessary, it
will be required to configure the serial numbers of the new ac-
tuator. Four individual numbers make up this serial number
and these can be programmed to match the serial number of the
actuator in its Hydronic Heating Actuator Configs group,
ACT.C ( SN.1, SN.2, SN.3, SN.4 ). See Fig. 9.
Fig. 9 — Actuator Serial Number Configuration
NOTE: The serial numbers for all actuators can be found inside
the control doors of the unit as well as on the actuator itself. If an
actuator is replaced in the field, it is a good idea to remove the ad-
ditional peel off serial number sticker on the actuator and cover up
the old one inside the control doors.
STAGED GAS HEAT CONTROL (
HT.CF = 3 AND HT.ST =
0, 1, OR 2)
As an option, the units with gas heat can be equipped with
staged gas heat controls that will provide from 2 to 9 stages of
heat capacity. This is intended for tempering mode and temper-
ing economizer air when in a cooling mode and the dampers
are at minimum vent position. Tempering can also be used
during a pre-occupancy purge to prevent low temperature air
from being delivered to the space. Tempering for staged gas,
modulating gas, and hydronic heat will be discussed in its own
section. This section will focus on heat mode control, which ul-
timately is relevant to tempering, minus the consideration of
the supply air heating control point.
MODULATING GAS HEAT CONTROL (
HT.CF = 3 AND
HT.ST = 3, 4, OR 5)
As an option, the units with gas heat can be equipped with
modulating gas heat controls that will provide infinite stages of
heat capacity. This is intended for tempering mode and temper-
ing economizer air when in a cooling mode and the dampers
are at minimum vent position. Tempering can also be used
during a pre-occupancy purge to prevent low temperature air
from being delivered to the space. Tempering for staged gas,
modulating gas, and hydronic heat will be discussed in its own
section. This section will focus on heat mode control, which ul-
timately is relevant to tempering, minus the consideration of
the supply air heating control point.
The staged and modulating gas and SCR electric heat configu-
rations are located at the local display under Configura-
tion

HEAT

SG.CF . See Table 44.
Table 44 — Staged Heat Configuration
*Some configurations are model number dependent.
00 8 50 - 3 006 3 - 0 8 4 -0 83
ACTUATOR S ERIAL NUMBER
{
NOT
U S ED
{
S N.1
{
{
S N.2 S N. 3
{
NOT
U S ED
{
S N.4
S N.1 = 8 50
S N.2 = 3
S N. 3 = 6 3
S N.4 = 83
ITEM EXPANSION RANGE UNITS CCN POINT DEFAULT
SG.CF
STAGED HEAT CONFIGS
HT.ST Staged Heat Type 0 to 8 HTSTGTYP 0*
CAP.M Max Cap Change per Cycle 5 to 45 HTCAPMAX 45*
M.R.DB St.Ht DB min.dF/PID Rate 0 to 5 HT_MR_DB 0.5
S.G.DB St.Heat Temp. Dead Band 0 to 5 ^F HT_SG_DB 2
RISE Heat Rise dF/sec Clamp 0.05 to 0.2 HTSGRISE 0.06
LAT.L LAT Limit Config 0 to 20 ^F HTLATLIM 10
LIM.M Limit Switch Monitoring? Yes/No HTLIMMON Yes
SW.H.T Limit Switch High Temp 80 to 210 dF HT_LIMHI 170*
SW.L.T Limit Switch Low Temp 80 to 210 dF HT_LIMLO 160*
HT.P Heat Control Prop. Gain 0 to 1.5 HT_PGAIN 1
HT.D Heat Control Derv. Gain 0 to 1.5 HT_DGAIN 1
HT.TM Heat PID Rate Config 30 to 300 sec HTSGPIDR 90*