Viessmann AirflowPLUS AH2A Series, AirflowPLUS AH2A-354, AirflowPLUS AH2A-385, AirflowPLUS AH2A-213 Technical Data Manual

Technical Data Manual

Model Nos. and pricing: see Price List

Viessmann AirflowPLUS AH2A series
Hydronic forced air handler

Viessmann Airfl owPLUS

Product may not be exactly as shown

Viessmann AirflowPLUS

AH2A Series, Models 213, 354 and 385
The Viessmann AirflowPLUS works directly with other
hot water sources to provide warm comfortable heating
for any home or small commercial building.

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Viessmann AirflowPLUS AH2A Series

Viessmann AirflowPLUS AH2A Technical Data

The Viessmann AirflowPLUS Series is engineered to
be used with hydronic (boiler) systems, tank-less or on
demand water heaters and domestic water systems
(combo systems or aqua systems). Combo water systems
use the homes hot water heater to provide both space
heating and domestic hot water, eliminating the need for
a furnace. Outputs range from 28,000 BTUH to 115,000
BTUH.

The benefits at a glance:

■ Total Comfort: Delivers warm comfortable conditioned

air, warmer than heat pumps and many furnaces.

■ Quiet performance: Engineered and balanced with extra

insulation for quiet operation.

■ Dependable: Manufactured to precise specifications,

using high performance components.

■ Accessories: Prewired for heating, cooling, and

electronic air cleaners.

Components

■ Multi-position: Unit mounts in any direction - upflow,

downflow or horizontal discharge right or left. Use built
in filter rack for bottom return or add on external filter
rack for other return air options (included).

■ Ease of Service: All components slide out on rails for

easy maintenance and/or service.

■ Cooling: Pre-wired for A/C. Just add your favorite

evaporator coil and condensing unit from most
manufacturers.

■ Protection: Built-in safety sensors provide whole house

freeze protection, in case of thermostat failure.

■ All designs include an integral bottom return air filter

rack and air filter and a filter rack is also provided for
side return applications.

■ All models are compatible with standard or digital

thermostats.

Cabinet

All cabinets have a tough, durable powder coat finish
on satin coat 20 gauge steel.

Heating coils

All heating coils are copper and assembled using no lead
solder. All coils and internal piping conform to ASTM
B-68, B-88 and/or B-743 standards.
High density aluminum fins provide maximum heat
transfer for small coil surface.

Legend

A Standard adaptors (at the rear)
B Heating coil and pump slide out for easy service
C Integrate pump with check valve
D Fibreglass insulation with reinforced foil face and

gasket seals

E Fan and controls slide out on rails
F Integrated filter rack

2

Fan and motor

The fan is a wide body dynamically balanced for extra
quiet operation. Multi-directional sleeve bearing motors
allow mounting in any direction for maximum installation
flexibility.

Circulating pump

The internal circulating pump is matched for maximum
performance. All Viessmann AirflowPLUS air handlers come
with internally mounted pumps for ease of installation.

Check valve

A check valve is built into the circulator to protect against
backflow of water.

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Viessmann AirflowPLUS AH2A Technical Data

Technical Data

Description AH2A-213 AH2A-354 AH2A-385

Motor (ECM) hp
Motor rated amps - loaded

(1050 RPM) AMPS 5.0 7.7 9.6

- locked rotor AMPS ** ** **
Electrical VOLTS/PH/HZ 120/1/60 120/1/60 120/1/60
Heating BTUH

120°F (49°C) 28,000

(kW)

140°F (60°C) 46,000

160°F (71°C) 62,000

180°F (82°C) 72,000

Flow USG/min

(L/H)

Nominal (CFM) Heating .5” e.s.p.

Cooling .5” e.s.p.

Heating .2” e.s.p.

Cooling .2” e.s.p.
Cooling capacity (tons) 1.5 - 3.0 2.50 - 4.0 3.5 - 5.0
Cabinet D x W x H* in.

(mm)

22c x 18 x 32b

(578 x 457 x 825)

Supply air opening in.

(mm)

Return air opening in.

(mm)

Weight lb.

kg

Circulating pump *

Type Grundfos 15/58RU
Volts AC 115 115 115
Motor horsepower hp 1/25 1/25 1/25
Capacitor MFD/VOLTS 10/180 10/180 10/180
Motor rated amps - loaded AMPS 0.74 0.74 0.74

- locked rotor AMPS 4.44 4.44 4.44
Maximum working pressure PSI 145 145 145
Min./max. fluid temperature ºF

(ºC)

Hydronic heating coil

Construction Copper tubing, aluminum fins, galvanized steel support frame
Rows...fins/in. 3...12 3...12 3...12
Total face area sq. ft. (m

2

) 1.3 (0.12) 2.8 (0.26) 2.8 (0.26)

Piping connections

Supply in.
Return in.
Pressure drop through the coil feet of head

[@ 160°F (71°C)

supply water
temperature]

gbc

(8)

(13)

(18)

(21)

3

(681)

600

700
1,100
1,200

16 x 20

(406 x 508)

14 x 18

(356 x 457)

85

(39)

120/200

(49/93)

44,000

(13)

61,000

(18)

83,000

(24)

98,000

(29)

5

(1135)

1,200
1,400
1,300
1,600

23 x 22 x 34b

(584 x 559 x 876)

20 x 20

(508 x 508)

18 x 18

(457 x 457)

100
(45)

120/200

(49/93)

51,000

(15)

74,000

(22)

90,000

(26)

115,000

(33)

5

(1135)

1,600
1,800
1,900
2,100

28 x 22 x 34b

(711 x 559 x 876)

20 x 25

(508 x 635)

18 x 23

(457 x 584)

110
(50)

120/200

(49/93)

b FIP c FIP c FIP
b FIP c FIP c FIP

12 2 2

* Using the adjustable levelling feet can add up to 1b in. (38 mm) to the height of the air handler.
** If motor speed decreases below the programmed stall speed, the motor will shut down and after a delay period,
the control will attempt to restart the motor. Starting current is limited to significantly less than full load current.

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Dimensions

Viessmann AirflowPLUS AH2A Technical Data

IMPORTANT

The maximum ambient temperature must not exceed
104ºF (40ºC).

Top view

AH2A-213 AH2A-354 AH2A-385

a in.

(mm)

b in.

(mm)18(457 mm)22(559 mm)22(559 mm)

c* in.

(mm)

d* in.

(mm)

e* in.

(mm)

f in.

(mm)2(51 mm)

g in.

(mm)3(76 mm)

h in.

(mm)

* Using the adjustable levelling feet can add up to 1b in.
(38 mm) to the height of the air handler.

Legend

A Heating water supply connection
B Heating water return connection

22c

(578 mm)

32b

(826 mm)

22a

(572 mm)

23b

(597 mm)

24c

(629 mm)

23

(584 mm)28(711 mm)

34b

(876 mm)

24e

(620 mm)

25b

(650 mm)

1c

(44 mm)

3f

(92 mm)

25

(635 mm)30(762 mm)

34b

(876 mm)

24e

(620 mm)

25b

(650 mm)

1c

(44 mm)

3f

(92 mm)

Front view Side view

4

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Viessmann AirflowPLUS AH2A Technical Data

Minimum Clearances

Horizontal Installation

Vertical Installation

Recommended minimum service clearances

For typical Viessmann AirflowPLUS installation, it
is recommended to install the air handler with the
clearances shown in the illustration.

a - 24 in. (610 mm)
b - 12 in. (305 mm)

These dimensions reflect the recommended service
clearance for the air handler only, ensure adequate clearance
is left for the installation of ducting, piping and electrical
connections. Only the b clearance may be reduced providing
there is enough clearance for ductwork, plumbing and
electrical connections, with zero clearance between the air
handler unit and ducting being acceptable.

Heating Circuit Pumps

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Pump Model Grundfos UPS15-58RU

Rated voltage VAC 115
Rated current Amp 0.74
Capacitor
Power consumption Watts 87

Legend

A Speed 1 Pump curve
B Speed 2 Pump curve
C Speed 3 Pump curve

Note: All Viessmann AirflowPLUS air handlers come with
pump speed factory set to speed 3.

F

10

5

Electrical Connections

WARNING

DISCONNECT POWER BEFORE
SERVICING BOILER.

If any of the original wires as
supplied with the appliance must be
replaced, it must be replaced with
the exact equivalent.

CAUTION

Label all wires prior to disconnection
when servicing controls. Wiring errors
can cause improper and dangerous
operation. Verify proper operation
after servicing.

Viessmann AirflowPLUS AH2A Technical Data

External Connections

Internal Connections

Power Connection
Terminal

Main power supply

120VAC, 1Ph, 60Hz, 12A

Main
Disconnect
Switch

>

Door Safety
Switch

Viessmann AirflowPLUS

Connection Board

AC Line

PMP

XFO

XFI

ECM
Power

ECM
Control

Stage 1 Cool

Stage 1 Heat

Thermostat - field supplied

(optional two stage

cooling shown)

6

24VAC

Fan Speed

Stage 2 Cool

24VAC COM

A/C Relay

Dry Contacts

Heat Fan

Alarm

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Viessmann AirflowPLUS AH2A Technical Data

9

8

7

5

4

3

2

1

Electrical Connections (continued)

Legend

1 Diagnostic LED
2 Ambient temperature sensor
3 Return air temperature sensor
4 Supply air temperature sensor
5 Freeze protection temperature sensor
7 Supply water temperature sensor
8 A/C power
9 Pump motor
10 24VAC transformer secondary
11 24VAC transformer primary
12 ECM power
13 ECM control

Legend

AC Line

1 115VAC line
2 115VAC neutral

Pump (PMP)

1 115VAC neutral
2 115VAC line

XFO

1 24VAC
2 N/C
3 24VAC-COM (GND)

XFI

1 115VAC line
2 115VAC neutral

ECM Power

1 N/C
2 N/C
3 N/C
4 115VAC neutral
5 115VAC line

ECM Control

1 Common C1
2 W/W1
3 Common C2
4 Delay tap select
5 Cool tap select
6 Y1
7 Adjust tap select
8 Output
9 Return valve (heat pump only)

qP Humidistat (BK)
qQ Heat tap select
qW 24VAC (R)
qE 2nd stage heat (EM/W2)
qR 2nd stage cool (Y/Y2)
qT Fan (G)
qZ Output +

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Viessmann AirflowPLUS AH2A Technical Data

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