Ferroli RXA Technical Manual

RXA

AIR-WATER CHILLERS AND HEAT PUMPS
WITH AXIAL FANS

TECHNICAL MANUAL

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TABLE OF CONTENTS

GENERAL FEATURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5

UNIT DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5

UNIT IDENTIFICATION CODE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5

DESCRIPTION OF PARTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6

VERSIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7

ACCESSORIES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8

TECHNICAL DATA AND PERFORMANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

TECHNICAL DATA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

NOMINAL PERFORMANCE IR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10

NOMINAL PERFORMANCE IP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10

PERFORMANCE IN COOLING (IR AND IP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11

PERFORMANCE IN HEATING (IP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12

WEIGHTS OF UNITS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13

ELECTRICAL DATA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13

NOISE LEVELS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13

PRESSURE LOSSES (VERSION VB) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14

USEFUL HEAD (VERSION VP AND VA) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14

OPERATION LIMITS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15

DIMENSIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16

CONNECTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17

PLUMBING CONNECTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17

EXPANSION TANK SETTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18

ELECTRICAL CONNECTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19

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GENERAL FEATURES

Unit description

This series of air-water chillers and heat pumps has been designed to satisfy the air conditioning requirements of residential and
commercial plants of small and medium size and can be applied both to fan coil plants and to radiant floor plants.
All the units are suitable for outdoor installation. The bearing structure and the panels are realized with galzanized and coated
metal sheets to ensure a good protection against adverse weather conditions.
All the units are equipped with a compressor (rotary or scroll depending on the model), axial fans with safety protection grilles,
finned coil realized with copper tubes and aluminium louvered fins, brazed plate heat exchanger thermically insulated to reduce
heat dispersions and to avoid condensate generation and protected by means of a water differential pressure switch and of an
antifreeze electrical heater.
As part of the standard outfit the units are equipped with variable speed control of the fans in order to allow the units to operate
both with low outdoor temperature in cooling mode and with high outdoor temperature in heating mode as well as to reduce noise
emissions in such operating conditions. All three-phase power supply units are provided with a phase presence and sequence
monitoring device as part of the standard outfit.
Each model is available in 3 versions in order to match the different installation requirements :

- base version

- pump version

- pump and storage tank version.

The units operate with R410A refrigerant gas.
All the units are accurately built and individually tested in the factory. Only electric and hydraulic connections are required for
installation.

IP 14.1 VB AB 0 M 5

VB - Basic Version
VP - Pump Version
VA - Storage Version

Unit version

(1) : Mod. 6 - 7 - 9 - 11
(2) : Mod. 9 - 11 - 14 - 1 7

1 - 230V - 1 - 50 Hz

(1)

5 - 400V - 3N - 50Hz

(2)

Unit identification code

The codes that identify the units and the meaning of the letters used are described below.

AB - Standard Preparation

Acoustic setting up

0 - R410A

Refrigerant type

M - Average temperatures.
The unit is suitable for
installation in places with
temperate climates.

Operating climate

Power supply

IR - unit for installation in a
hydronic system operating as
a cooler.
IP - unit for installation in a
hydronic system operating as
a heat pump.

Unit type

Unit model

N° of compressors

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GENERAL FEATURES

Description of parts

The supporting structure (1), base and external panelling are
made from hot galvanised steel sheet, painted with epoxy
powers (colour RAL 7035) to ensure good resistance to
atmospheric agents.

The axial-type fans with curved profile blades (2)are housed in
a sheet casing and are complete with safety grille. Fan speed
is controlled in a continuous way by a phase cut device that
allows the condensing pressure (in cooling) and evaporation
pressure (in heating) to be controlled according to the value
read by the temperature probe on the liquid line.

The rotary type hermetic compressor (3) (models 6 or 7) or
scroll (models 9, 11, 14 and 17) is complete with
overtemperature and overcurrent protection. It is fixed to the
base by means of rubber vibration dampers and placed in a
compartment separate from the air flow to facilitate
maintenance and control operations. To prevent reverse
compressor rotation on all the units with three-phase power
supply, a device that controls the presence and correct
sequence of the power phases is fitted. Units in heat pump
version have a heating element that is activated when the
compressor switches off, to keep the compressor crankcase oil
temperature high enough to prevent migration of the refrigerant
during winter stops and to evaporate any liquid present in the
crankcase, in order to prevent possible liquid rushes on
starting.

The braze-welded stainless steel plate-type exchanger on the
user side (4) is adequately insulated to prevent the formation
of condensate and to limit heat loss to the outside. It is protected against the risk of ice forming by an antifreeze heating element
activated according to the water temperature and by a differential pressure switch that detects a possible lack of water flow.

The external side exchanger (5) comprises a finned coil with grooved copper pipes arranged in an equilateral shape and
aluminium fins with notched profile to increase the heat exchange coefficient. A tray is obtained in the base for collecting the
condensate produced during heating operation.

The lamination part comprises a thermostatic valve (6) with external equaliser that allows the unit to adjust to the various
operation conditions, keeping the set level of overheating constant.
The refrigerant circuit of each unit is also complete with :

- hermetic dehydrator filter with solid cartridge (7) : it catches residuals of impurities and any traces of moisture in the circuit;

- high pressure switch (8) : with fixed setting and manual reset;

- low pressure switch (9) : with fixed setting and automatic reset (it becomes manual only in case of frequent activations);

- 4-way reverse cycle valve (10) : it allows the switching of operation mode, reversing the refrigerant flow (for units in heat pump
version only);

- liquid receiver (11): it compensates the variation in refrigerant charge required with the change of operation mode (for units in
heat pump version only);

- pressure test points (12) SAE 5/16” (UNF 1/2” - 20) complete with pin, seal and blind union, as required for the use of
refrigerant R410A. They enable a complete check of the refrigerant circuit : compressor inlet pressure, compressor delivery
pressure, pressure upstream of the thermostatic valve and pressure losses on the dehydrator filter.

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