NTI INSTALLATION MANUALS

Part 7 - Connecting Electrical Service

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OUT1

OUT2

FLUE RETURN

DHW

TANK OUTDOOR

SYSTEM

3 WAY VALVE

HMI

Ebus

NEUTRAL B Hf A C

C

C A

C A

G

G

G

G

HMI

SENSORS CIRCUIT

3 WAY VALVE CIRCUIT

A

COMMUNICATION

uP

B

Nf C G

C

G

G

D

G

A

A

FAN

FLAME

RELAYS

CIRCUIT

CIRCUIT

CIRCUIT

GAS VALVE CIRCUIT

Nf

B

Nf

Hf

Hf

FAN

IGNITER

GAS VALVE

BOILER PUMP

OVERHEAT INPUT

EXTERNAL PUMPS

FLAME ELECTRODE

N

Nf

D

C

G

SMPS

FILTER

B

HOT

NEUTRAL

Nf HOT filterd Hf

D +5 Vdc A NEUTRAL filtered

G +24 Vdc C +5 Vdc for SAFETY MCU B Safety Ground

Step-up 250V paek from +24 Vdc

A

HOT

F5AT

H

N

H

Hf

Figure 54 - Ladder Diagram

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