Hvac partners Ehc09akcn User manual

482 01 2231 02 4/27/15

Specifications are subject to change without notice

INSTALLATION INSTRUCTIONS

ELECTRIC HEAT ACCESSORY

EHC09AKCN, EHC15AKF, EHC15AKB, EHC20AKF, EHC20AKB,

EHC25AHCF, EHC30AHCF

DANGER, WARNING, CAUTION, and NOTE

The signal words DANGER, WARNING, CAUTION, and NOTE

are used to identify levels of hazard seriousness. The signal

word DANGER is only used on product labels to signify an im-

mediate hazard. The signal words WARNING, CAUTION, and

NOTE will be used on product labels and throughout this manual

and other manuals that may apply to the product.

DANGER −Immediate hazards which will result in severe per-

sonal injury or death.

WARNING −Hazards or unsafe practices which could result in

severe personal injury or death.

CAUTION −Hazards or unsafe practices which may result in

minor personal injury or product or property damage.

NOTE −Used to highlight suggestions which will result in en-

hanced installation, reliability, or operation.

Signal Words in Manuals

The signal word WARNING is used throughout this manu-

al in the following manner:

The signal word CAUTION is used throughout this manu-

al in the following manner:

Signal Words on Product Labeling

Signal words are used in combination with colors and/or

pictures on product labels.

WARNING

Safety Labeling and Signal Words

CAUTION

WARNING

ELECTRICAL SHOCK HAZARD.

Failure to follow this warning could result in

death and/or personal injury.

Installation or repairs made by unqualified persons

can result in hazards to you and others. Installation

must conform with local building codes or, in the

absence of local codes, with National Electrical Code

ANSI/NFPA 70−1996 or current edition.

The information contained in this manual is intended

for use by a qualified service technician familiar with

safety procedures and equipped with the proper

tools and test instruments.

Shut OFF electric power at unit disconnect and/or

service panel before beginning the following proce-

dures.

!WARNING

USE

EHC heater kits are designed for use with the Observert

Communicating Wall Control and FCM4X communicating fan coil.

When used with the Observer communicating system the electric

heater will be automatically recognized and the airflow will be

configured automatically.

INSTALLATION

INSTALL ELECTRIC HEATER ASSEMBLY

NOTE: Ensure heater coils are not deformed or damaged during

heater installation.

1. Make sure power to unit is off.

2. Remove blower access panel of fan coil unit.

UNIT DAMAGE HAZARD.

Failure to follow this caution may result in property

damage.

Before installation of heater, the black and yellow

pigtail leads must be removed from the fan coil board

or wire harness to prevent possible damage to the

product. Electrical power will be provided to the

board through the heater circuit plug.

!CAUTION

3. Disconnect 2 power wires (black and yellow pigtail leads) from

fan control board or wire harness (if applicable) and discard.

Wires may be part of a plug assembly or attached to terminals

L1 and L2. Remove cooling control plate from fan coil (if

equipped). For 24kW, and 30kW heaters, remove adapter plate.

(See Figure 1)

4. Insert heater assembly into front of fan coil so that element rods

engage holes in rear heat shield.

5. Attach heater control plate to fan coil using 2 screws provided.

For 24kW, and 30kW heater models, attach front of heater to fan

deck using third screw. (See Figure 1)

482 01 2231 02 2

Specifications are subject to change without notice

Figure 1 Installing The Electric Heat Accessory

Table 1 −Accessory Heater Usage

Part Number Description Use with Model Sizes

EHC09AKCN3 9 kW, single phase, no internal circuit protection ALL

EHC15AKF3* 15 kW, single phase, with fuses ALL

EHC15AKB3*† 15 kW, single phase, with circuit breakers ALL

EHC20AKF3* 20 kW, single phase, with fuses ALL

EHC20AKB3*† 20 kW, single phase, with circuit breakers ALL

EHC25AHCF3 24 kW, supplied as 3 phase, field convertible to single phase, with fuses 48 −60

EHC30AHCF3 30 kW, supplied as 3 phase, field convertible to single phase, with circuit breakers 48 −60

† EHC15AKB3 & EHC20AKB3 are not approved for use in Canada (must use fused heaters and certified single point wiring kit).

* 15kW & 20kW are not recommended for specific heat pump applications, see AIRFLOW DELIVERY (CFM)

HEAT PUMP MINIMUM CFM WHEN USING ELECTRIC HEAT (CFM)

FCM

Model Size

Outdoor

Unit Size

Heater Size kW

9 15 20 24, 30

18 625 −− −− −−

24 725 875 −− −−

30 875 875 1040 −−

36 970 970 1040 −−

24 875 −− −− −−

30 875 1100 1150 −−

36 975 1100 1225 −−

42 1125 1125 1225 −−

30 875 875 1150 −−

36 975 1100 1225 −−

42 1125 1125 1225 −−

48 1305 1305 1305 1400

36 1100 1350 1350 −−

42 1125 1350 1350 −−

48 1300 1350 1465 1750

60 1625 1625 1750 1750

A/C MINIMUM CFM WHEN USING ELECTRIC HEAT (CFM)

FCM

Model Size

Heater Size kW

9 15 20 24, 30

Heater Only

625 725 875 −−

36 700 850 1050 −−

48 700 850 1050 1400

60 1050 1050 1050 1750

NOTES:

1. Heater Only−Air conditioner with electric heater application.

2. These airflows are minimum acceptable airflows as UL listed. Actual airflow delivered will be per airflow delivery chart for Electric Heating

Modes.

482 01 2231 02

3Specifications are subject to change without notice

ATTACH FUSE BOX OR CIRCUIT BREAKER BOX

1. For 15kW and 20kW fused models:

After installing heater assembly, attach fuse assembly to side of

fan coil unit by inserting fuse box tab between insulation and to

left side of unit and fan deck. Mount front of assembly to side

flange with two (2) screws provided. On fan coil units size 4200

and larger, remove wire tie that shortens wire length between

heater and fuses. Fuse cover is closed by engaging dimples in

fuse box. (See Figure 2)

2. For 24kW and 30kW fused models:

Fuse assembly is mounted on heater. Be sure fuse cover is

closed by engaging clip latch on unit top panel. (See Figure 1)

ELECTRICAL SHOCK.

Failure to follow this warning could result in death and/or

personal injury.

Close fuse box before power is turned to ON position.

!WARNING

3. For 5kW through 20kW circuit breaker models:

After installing heater assembly, attach circuit breaker assembly

to unit with screws provided. (See Figure. 3) On fan coil units

size 4200 and larger, remove wire tie that shortens wire length

between heater and circuit breaker assembly to allow mounting

of circuit breaker assembly. (See Figure 3)

4. Circuit breaker models require installing a bezel in unit door to

provide safe access to circuit breakers. Bezel mounts on inside

of blower door. (See Figure 4)

Figure 2 Fused Model Installation

a. Cut insulation away from access hole in blower access panel.

Slide bezel flanges under insulation. Lip on bezel must protrude

inward toward unit.

b. Secure bezel to panel with two (2) No. 6 hex head screws. Insert

screws through original cover plate holes on access panel and

drive into engagement holes on bezel flanges.

ELECTRICAL CONNECTIONS

Refer to unit instructions for recommended wiring procedures.

Install wiring in accordance with all applicable local and national

codes.

Connect heater wiring harness plug to receptacle on fan control

board or wire harness. A positive connection must be made

between plug and receptacle. Plug will interlock with receptacle

when properly seated. Harness contains both 24V control and

high−voltage wiring. Blower power is provided through heater

harness.

NOTE: Units with or without electric heaters require a minimum

CFM. Refer to unit wiring label to ensure the fan speed selected with

electric heaters is equal to or greater than the minimum fan speed

indicated. The minimum CFM for cooling is determined by the

outdoor unit requirements. Use the higher of the two for year−round

operation.

Figure 3 Circuit Breaker Model Installation

A. Wire 24V Control Systems

1. Connections to unit

Use No. 18 AWG color−coded, insulated (35 Deg. C minimum)

wire to make low−voltage connections between thermostat, fan

coil unit, and outdoor unit. If thermostat is located more than 100

ft. from unit (as measured along the low−voltage wire), use No.

16 AWG color−coded, insulated (35 Deg. C minimum) wire. All

wiring must be separated from line voltage power leads. Refer

to outdoor unit wiring instructions for additional wiring procedure

recommendations.

2. Transformer

Transformer is factory wired for 230V operation. For 208V ap-

plications, disconnect black wire on transformer 230V terminal

and reconnect it to 208V terminal. (See Figure 5) The secondary

circuit of transformer is protected by a 5−amp fuse mounted on

fan control board.

3. Heater staging

The units are shipped circuited for single stage operation and

the Observer Wall Control only supports single stage operation.

4. Rectifier and Time Delay Boards

Each heater element is controlled by a relay mounted on the

heater panel. The relay has a 24V DC coil. Each relay has a

small rectifier board attached directly to relay coil terminals. The

rectifier board converts incoming 24V AC control signal to DC.

Some heaters may have up to three relays. These relays are for

future use with a control capable of staging the electric heat. The

second and/or third relay rectifier board also has a time delay

feature and a small jumper wire built into it. With the jumper un-

cut, the time delay allows the second stage heat to be energized

approximately five (5) seconds after the first stage. On 24kW,

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Specifications are subject to change without notice

and 30kW heaters, the third stage relay board jumper is cut at

factory. This provides an eight (8) second delay after first stage

relay closes.

Figure 4 Bezel Installation

A03069

Installation of Window Bezel for Circuit Breaker Model Heater

B. Power Connections

NOTE: Heater supply circuit wire size and overcurrent protection

must comply with National Electrical Code (NEC) and UL branch

circuit requirements. (See Table 3) Wires and overcurrent

protection, integral to the heater, are not required to meet branch

circuit requirements. Internal circuit protection of 60 amps

(maximum) is acceptable.

1. Unprotected heaters: (See Figures 6, 10, and 11)

a. The 9kW single phase and 15kW three phase heaters can be

wired for single supply circuit only. Supply circuit connects to

heater pigtail leads.

b. The 9kW single phase heaters can use a separate field−

installed, factory−authorized disconnect kit which installs in fan

coil.

NOTE: Refer to wiring label for component locations.

c. The 9kW heater is factory wired for single supply circuit, single

phase. To convert heater to single supply circuit, three phase:

(1.) Disconnect blue wire from relay 1 terminal 6. Cut, strip, and

connect to field wire L3.

(2.) Disconnect yellow wire from relay 3 terminal 6 and connect

to relay 1 terminal 6.

(3.) Disconnect blue wire from relay 3, terminal 2, and connect

to relay 3 terminal 6.

2. Circuit breaker heaters: (See Figures 7 and 9)

The 15kW and 20kW heaters can be wired for dual−supply circuits

only.

3. Fused heaters: (See Figures 8, 12, 13, and 14)

a. The 15kW and 20kW heaters can be wired for single or dual

supply circuits. Single supply circuit wiring requires a factory

authorized, single−point adapter kit.

b. The 24kW and 30kW heaters can be wired for single or multiple

supply circuits. Heaters are factory wired for single circuit three

phase. To convert heaters to single circuit single phase, discon-

nect yellow lead from L3 and connect to L1. Disconnect black

lead from L3 and connect to L2. To convert heaters to multiple

supply circuit single phase, remove and discard leads between

single circuit terminal block and fuse block. Remove and discard

single circuit terminal block. Attach L1 through L6 power leads

as indicated on label next to fuse block.

C. Ground Connections

ELECTRICAL SHOCK.

Failure to follow this warning could result in property

damage and/or death.

According to NEC, ANSI/NFPA 70, and local codes,

cabinet must have an uninterrupted or unbroken ground

to minimize personal injury if an electrical fault should

occur. The ground may consist of electrical wire or metal

conduit when installed in accordance with existing

electrical codes. (See Ground/Conduit Note below.)

!WARNING

NOTE: Use UL−listed conduit and conduit connector for connecting

supply wire(s) to unit to obtain proper grounding. If conduit

connection uses reducing washers, a separate ground wire must be

used. Grounding may also be accomplished by using grounding

lugs provided in control box.

1. For unprotected or single circuit heaters, 1 equipment ground

connection is provided on fan coil unit. (See Figure 1 or 2)

2. For 15kW and 20kW circuit breaker heaters, an additional

ground lug is provided on circuit breaker mounting bracket for dual

circuit grounding. (See Figure 3)

3. For 15kW and 20kW fused heaters, an additional ground lug is

provided on fuse mounting bracket for dual circuit grounding. (See

Figure 2)

4. For 24kW and 30kW fused heaters, two (2) additional ground

lugs are provided for single phase, multi circuit wiring. (See Figure

D. FAN SPEED SELECTION

FCM

The FCM fan coil with the Observer Wall Control will automatically

select the appropriate airflow for the selected heater size. Refer to

airflow/CFM tables for airflow delivery.

CONVERSION OF CIRCUIT BREAKER FOR DOWNFLOW

APPLICATIONS

1. Tag and disconnect factory wiring from terminals on circuit

breaker(s).

2. Pull white plastic release tab on the bottom of circuit breaker

straight out to release circuit breaker from bracket. (See Figure 16)

3. Remove quick connect adapters from factory side of breaker(s).

Reinstall adapters on other end of breakers(s). Be sure adapter is

located between lug screw and plate. Torque lug screw to 30−in−.lb.

4. Rotate breaker 180 degrees from its original position and reinstall

in bracket. Slide breaker slot into sheet metal tab and snap breaker

into place. Make sure both tabs engage breaker. Reconnect wiring

on opposite end. Make sure wires are positioned as before.

5. Remount circuit breaker bracket into unit so that the switch will be

in UP position when ON.

ATTACH WIRING DIAGRAM AND RATING LABEL

Attach heater rating label included with kit over existing electrical

information label located on front access panel of fan coil. (See

Figure 17) If kit contains multiple rating labels, ensure correct label

is applied (check phase and supply circuits).

VERIFY INSTALLATION

After completion of heater installation, check wiring to ensure

tightness and that proper connections and routings have been

made. Ensure all electrical covers are in place and proper labels

have been applied. Reinstall blower access panel before turning

unit power on.

482 01 2231 02

5Specifications are subject to change without notice

Figure 5 Connection of Transformer

230

208

BRN

RED

YEL

BLK

SECONDARY

PRIMARY

A94067

Figure 6 9 kW Non−fused Heaters

Figure 7 15 and 20 kW Fused Heaters

Figure 8 15 and 20 kW Circuit Breakers

Figure 9

lug

15 kW 3−Phase Heater

Figure 10 24 and 30 kW Heaters

482 01 2231 02 6

Specifications are subject to change without notice

Figure 11 24 and 30 kW Heaters

Figure 12 24 and 30 kW Heaters

Figure 13 Conversion of Circuit Breaker

Figure 14 Heater Rating Label Location

7 482 01 2231 02

Specifications are subject to change without notice

ELECTRIC HEATER ELECTRICAL DATA

Heater Model Heater kW PHASE

INTERNAL

CIRCUIT

PROTECTION

HEATER AMPS

208/230V

BRANCH CIRCUIT

Min Ampacity k

208/230V

Min Wire Size (AWG)

208/230V 1

Min Gnd Wire Size

208/230V

Max Fuse/Ckt Bkr Amps

208/230V

Max Wire Length

208/230V (Ft)‡‡

Single

Circuit

Dual Circuit Single

Circuit

Dual Circuit Single

Circuit

Dual Circuit Single

Circuit

Dual Circuit Single

Circuit

Dual Circuit Single

Circuit

Dual Circuit

230v 208v L1,l2 L3,L4 L1,L2 L3,L4 L1, L2 L3, L4 L1, L2 L3,L4 L1,L2 L3,L4 L1,L2 L3,L4

EHC09AKCN3{9 6.8 1 None 32.8/36.0 — — 49.5/53.5 — — 8/6 — — 10/10 — — 50/60 — — 54/87 — —

9 6.8 3 None 18.8/20.8 — — 32.0/34.5 — — 8/8 — — 10/10 — — 35/35 — — 83/85 — —

EHC15AKF3 15 11.3 1 Fuse 54.2/59.9 36.2/40.0 18.1/20.0 76.3/83.4 53.8/58.5 22.7/25.0 4/4 6/6 10/10 8/8 10/10 10/10 80/90 60/60 25/25 88/89 78/80 75/76

EHC15AKB3 15 11.3 1 Ckt Bkr — 36.2/40.0 18.1/20.0 — 53.8/58.5 22.7/25.0 — 6/6 10/10 — 10/10 10/10 — 60/60 25/25 — 78/80 75/76

EHC20AKF3 20 15.0 1 Fuse 72.3/79.9 36.2/40.0 36.2/40.0 98.9/108.4 53.8/58.5 45.3/50.0 3/2 6/6 8/8 8/6 10/10 10/10 100/110 60/60 50/50 85/109 78/80 59/59

EHC20AKB3 20 15.0 1 Ckt Bkr — 36.2/40.0 36.2/40.0 — 53.8/58.5 45.3/50.0 — 6/6 8/8 — 10/10 10/10 — 60/60 50/50 — 78/80 59/59

EHC25AHCF3}24 18.0 3 Fuse 50.1/55.4 — — 71.2/77.8 — — 4/4 — — 8/8 — — 80/80 — — 94/95 — —

24 18.0 1 Fuse 86.7/95.5 — — 116.9/127.9 — — 1/1 — — 6/6 — — 125/150 — — 115/116 — —

EHC30AHCF3}30 22.5 3 Fuse 62.6/69.2 — — 86.8/95.0 — — 3/3 — — 8/8 — — 90/100 — — 97/98 — —

30 22.5 1 Fuse 109.0/120.0 — — 144.8/158.5 — — 0/00 — — 6/6 — — 150/175 — — 117/150 — —

FIELD MULTIPOINT WIRING OR 24 AND 30 KW SINGLE PHASE

Heater Model

Heater kW

Heater Amps 208/230V Minimum Circuit Ampacity

208/230V k

Minimum Wire Size (AWG)

208/230V}Min Gnd

Wire Size

208/230V

Max Fuse/Ckt Bkr Amps

208/230V

Max Wire Length 208/230V

(FT)}}

L1, L2 L3, L4 L5, L6 L1, L2 L3, L4 L5, L6 L1, L2 L3, L4 L5, L6 L1, L2 L3, L4 L5, L6 L1, L2 L3, L4 L5, L6

230V 208V

EHC25AHCF3}24 18.0 1 28.9/32.0 28.9/32.0 28.9/32.0 44.7/48.5 36.2/40.0 36.2/40.0 8/8 8/8 8/8 10/10 45/50 40/40 40/40 59/60 73/73 73/73

EHC30AHCF3}30 22.5 1 36.2/40.0 36.2/40.0 36.2/40.0 53.8/58.5 45.3/50.0 45.3/50.0 6/6 8/8 8/8 10/10 60/60 50/50 50/50 78/80 59/59 59/59

Notes:

1Copper wire must be used. If other than uncoated (non−plated), 75°C ambient, copper wire (solid wire for 10 AWG and smaller, stranded wire for larger than 10 AWG) is used,

consult applicable tables of the National Electric Code (ANSI/NFPA 70).