NTI Matrix Installation And Operation Instructions Manual page 49

Matrix
Call for Heat (24VAC @ W1) – Normal Thermostat call, Matrix operates as a step-modulating furnace as
described above. If HRV set to 'ON', HRV will operate at the low (continuous) ventilation rate.
Call for Auxiliary Heat (24 VAC @ W2) – When calling, furnace will provide heat at a stage 10 output rate.
With a call for auxiliary heating the Matrix will function as a single stage, full fire appliance. This means the
burner will come on with a thermostat call and go off when the call is satisfied. If HRV set to 'ON', HRV will
operate at the low (continuous) ventilation rate.
Outdoor Sensor – The auxiliary heating function (24VAC @ W2) will utilize the outdoor sensor if available.
The outdoor reset function is not used for W1 heating. This function is also active during a hydronic heat
demand (24VAC @ H).
Plenum Sensor – The Matrix is equipped with a plenum temperature sensor that must be field installed in the
supply plenum and wired to the furnaces external terminal strip. When installed the Matrix fan control
displays the plenum temperature and will use it to detect problems in the supply of heat to the space.
Call for Circulating Fan (24VAC @ G) – Matrix operates at the programmed air circulation rate according to
the "FAN" setting in the Fan (blue) controller (400-1600 CFM). If HRV is set to 'ON' (see Section 13.0), the
HRV will ventilate at the low (Continuous) ventilation rate.
Call for Dehumidification (24VAC @ DH) – Matrix operates at the minimum air circulation rate (400 CFM).
HRV will ventilate at the high (Override) ventilation rate.
Call for Cooling Fan (24VAC @ Y1): Matrix operates at the prescribed air circulation rate (Y1x10 CFM – see
Section 13.0). HRV will not operate during a call for cooling unless there is a concurrent call for DH –
Dehumidification or G – Continuous and HRV is set to ON.
Call for Cooling Fan (24VAC @ Y2): Matrix operates at the prescribed air circulation rate (Y2x10 CFM – see
Section 13.0). HRV will not operate during a call for cooling unless there is a concurrent call for DH –
Dehumidification or G – Continuous and HRV is set to ON.
Duct Sizing
When sizing ductwork, a maximum flow velocity of 800 fpm is
desired. Table 14-2 shows common duct sizes at specified
flows. The maximum flows that can be expected are shown in
Table 14-3. It is important to maintain the return plenum
pressure as low as possible. Keeping this ductwork as free
flowing as possible will offer more supply static pressure to
overcome A/C coils, closed registers, etc while maintaining
constant flow.
Any additional filtration, humidification, or de-humidification
equipment should be installed external to the return or supply
ducts so not to create additional restriction.
Table 14-2 Duct Size vs. Air Flow
Airflow Area
(CFM) (sqft)
1600
2 24x12
1200
1.5 24x10
1000 1.25
800 1
Based on 800 fpm max airflow velocity
Duct Sizing
(inches)
20x16
20x12 18x12
20x10 18x10 16x12
18x8 16x10
Installation and Operation Instructions
Table 14-3 Maximum Air Flow Rates
Fan Control Setting
Heating
(HEA)
PF3
PF2
PF1
Example #1 No cooling function with Heating
profile of PF2 selected. Maximum airflow will be
1100 CFM.
Example #2
cooling with Heating profile of PF3 selected.
Maximum airflow will be greater of cooling or heating
function. Maximum 1200 CFM.
12x12
*Measured from return plenum to supply plenum
prior to A/C coil.
constant flow provided horsepower or maximum
speed of motor is not exceeded.
Cooling
ESPmax*
(COO)
160 max .35 inwg
160 max .6 inwg
160 max .75 inwg
120 (3 Ton)
80 (2 Ton)
No Cooling <1 inwg
No Cooling <1 inwg
No Cooling <1 inwg
Cooling set to 800 CFM for 2 tons of
ECM motor can produce near
CFM
1600
1500
1400
1200
800
1200
1100
1000
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