Double Flow HRV with Heat Recovery S&P CAD-COMPACT 500 ECOWATT

The S&P CAD-COMPACT 500 ECOWATT 5153135100 heat recovery unit is a double-flow mechanical ventilation system with heat recovery designed to continuously renew indoor air in commercial premises, offices, hospitality venues, public buildings, educational centers, and other tertiary installations. It uses a high-efficiency counterflow aluminum plate heat exchanger, low-consumption EC motor fans, and independent filtration in the supply and extract circuits.

This ECOWATT version is supplied without integrated control, but with its main components pre-wired in the electrical cabinet, including fans, bypass, filter pressure switches, and temperature probes. The unit also includes an external safety switch and is designed exclusively for horizontal installation.

Main features of the S&P CAD-COMPACT 500 ECOWATT

• Brand: Soler & Palau (S&P).
• Reference: 5153135100.
• Model: CAD-COMPACT 500 ECOWATT.
• Type: double-flow heat recovery unit.
• Installation: horizontal.
• Nominal airflow at 150 Pa: 440 m³/h according to the documentation linked to the reference.
• Heat recovery efficiency: 82.2% under nominal conditions.
• Heat exchanger: counterflow aluminum plates.
• Maximum efficiency of the range: up to 88%.
• Heat recovery unit certification: Eurovent.
• Air connections: Ø200 mm.
• Fans: plug fans with backward-curved blades.
• Motors: single-phase EC.
• Motor protection: integrated electronics.
• Motor protection rating: IP44.
• Motor insulation class: B.
• Supply filter: F7, ePM1 70%.
• Extract filter: M5, ePM10 50%.
• Internal bypass: yes, with actuator.
• Power supply: single-phase 230 V, 50/60 Hz.
• Maximum absorbed power: 0.31 kW, total of both fans.
• Maximum current: approximately 2.1 A.
• Weight: approximately 70 kg.
• Integrated control: no, ECOWATT version.

Double-flow ventilation with energy recovery

The CAD-COMPACT 500 operates through two independent air circuits. On one side it extracts stale air from inside the building, and on the other it introduces filtered outdoor air.

Both air streams pass through the heat exchanger without mixing. In this way, a significant part of the thermal energy contained in the exhaust air is transferred to the incoming fresh air, reducing the heating or cooling demand associated with air renewal.

High-efficiency counterflow heat exchanger

The unit incorporates a counterflow aluminum plate heat exchanger. This design keeps thermal exchange between the two air streams active for longer and achieves high recovery levels.

S&P states a nominal efficiency of 82.2% for the CAD-COMPACT 500 under the specified test conditions. The range can achieve higher performance at certain operating points, with maximum values close to 88%.

Nominal airflow of 440 m³/h at 150 Pa

For reference 5153135100, S&P technical documentation specifies a nominal airflow of 440 m³/h at 150 Pa available pressure.

The actual capacity depends on the pressure drop of the installation, duct length and diameter, filters, grilles, silencers, and other elements present in the ventilation network.

Plug fans with EC motors

The supply and extract circuits use plug fans with backward-curved impellers. This design is combined with high-efficiency EC motors to adapt the unit operation to the required working point.

The motors are single-phase and include integrated electronic protection, IP44 protection rating, and B insulation class.

Maximum absorbed power of 0.31 kW

The maximum absorbed power indicated for the CAD-COMPACT 500 is 0.31 kW, corresponding to the total of both fans.

The maximum current of the unit is approximately 2.1 A, with single-phase 230 V power supply at 50/60 Hz.

F7 filtration on supply air

The outdoor air entering the building passes through an F7 filter, classified as ePM1 70%, designed to retain a significant portion of fine particles before the air is introduced into occupied areas.

This filtration improves the quality of the supplied air and also protects the heat exchanger and internal components from dirt buildup.

M5 filter on extract air

The extract air circuit includes an M5 filter, ePM10 50%. Its function is to limit the entry of dust and particles from the building into the heat exchanger and extract fan.

The unit also allows the installation of a second additional filter inside, available as an accessory.

Filter fouling control

The ECOWATT version is supplied with pressure switches to monitor filter condition. These components detect the increase in pressure drop associated with clogging and help plan maintenance tasks.

Internal bypass with actuator

All CAD-COMPACT versions include an internal bypass with actuator. This system allows air to bypass the heat exchanger when thermal conditions make heat recovery undesirable.

With a compatible control system, it can be used, among other functions, for free-cooling strategies, taking direct advantage of outdoor air when its temperature allows the building to be cooled without recovering heat from the extracted air.

ECOWATT version without integrated control

Reference 5153135100 corresponds specifically to the ECOWATT version. Unlike the BASIC and ADVANCED variants, it does not include an integrated control system.

However, S&P supplies the unit with its main components pre-wired in the electrical cabinet:

• Fans.
• Bypass actuator.
• Filter pressure switches.
• Temperature probes.

This makes it possible to later complete the regulation using the compatible control systems provided by S&P or another control solution suitable for the project.

Included external safety switch

The heat recovery unit incorporates an external safety switch mounted on the unit. This element allows the unit to be electrically isolated during certain maintenance operations, always following the applicable safety procedures.

Four temperature probes

The manufacturer’s layout includes temperature probes to monitor the main air streams of the heat recovery unit:

• Supply air temperature.
• Outdoor air temperature.
• Extract or return air temperature.
• Exhaust air temperature.

These probes are part of the architecture used by the unit and compatible controls for bypass management and other regulation functions.

Galvanized steel construction

The casing is made of galvanized steel and features internal thermal-acoustic insulation with fire-retardant mineral wool.

In the CAD-COMPACT 500 size, S&P specifies 25 mm thick insulation with A1/M0 classification, intended to reduce thermal losses and limit noise transmission through the casing.

Ø200 mm circular connections

The CAD-COMPACT 500 uses Ø200 mm circular air spigots for its air connections.

The connections include a gasket to facilitate connection to the duct network and limit air leakage when the installation is carried out correctly.

CAD-COMPACT 500 dimensions

The main dimensions indicated by S&P for size 500 are:

• Length A: 1120 mm.
• Width B: 698 mm.
• Height C: 289 mm.
• Connection diameter: 200 mm.
• Weight: approximately 70 kg.

Its low-profile format is designed for horizontal installations, including suspended ceiling locations when the structure and available space allow the unit to be properly supported and maintained.

Horizontal installation only

The CAD-COMPACT range is designed only for horizontal installation. S&P provides specific supports to facilitate mounting in suspended ceilings and other compatible horizontal configurations.

Sufficient space must be ensured to open the maintenance access panels for fans, filters, electrical cabinet, and heat exchanger.

Minimum outdoor air temperature

S&P specifies a minimum outdoor air temperature of -10 °C for standard operation of the unit.

When lower temperatures are expected, the manufacturer indicates the need to install a preheating coil in the outdoor air intake to protect the heat recovery unit and ensure proper operating conditions.

Condensate drainage

The heat recovery unit includes a connection for condensate drainage. The installation must incorporate the necessary drain and trap according to the manufacturer’s instructions, especially in conditions where heat exchange produces condensation inside the unit.

Acoustic performance

For the CAD-COMPACT 500, S&P publishes the following sound pressure values, measured in free field at 3 meters:

• Intake: 38 dB(A).
• Discharge: 56 dB(A).
• Radiated by the casing: 37 dB(A).

The corresponding sound power levels are:

• Intake: 58 dB(A).
• Discharge: 76 dB(A).
• Radiated: 57 dB(A).

The actual acoustic levels inside the building will depend on the ducts, silencers, grilles, suspended ceiling, supports, and construction characteristics of the installation.

Available accessories

The CAD-COMPACT range offers different accessories to adapt the unit to the project, including:

• Replacement filters G4, M5, F7, and F9.
• SIL-200 circular silencers.
• Flexible connectors.
• Protective hoods.
• Support feet kit.
• Specific roof cover for CAD-COMPACT 500.
• External heating or cooling coils compatible with certain configurations.
• Control elements compatible with the ECOWATT version.

Applications of the S&P CAD-COMPACT 500

Soler & Palau recommends the CAD-COMPACT range for air renewal in installations such as:

• Commercial premises.
• Offices.
• Hospitality venues.
• Hotels and accommodation.
• Public buildings.
• Educational centers and schools.
• Tertiary spaces with double-flow mechanical ventilation.

Technical data of the S&P CAD-COMPACT 500 ECOWATT

• Manufacturer: Soler & Palau.
• Reference: 5153135100.
• Model: CAD-COMPACT 500 ECOWATT.
• Type: double-flow heat recovery unit.
• Configuration: horizontal.
• Control: ECOWATT version without integrated control.
• Nominal airflow at 150 Pa: 440 m³/h.
• Nominal heat recovery efficiency: 82.2%.
• Heat exchanger: counterflow aluminum.
• Fans: backward-curved plug fans.
• Motors: EC.
• Motor protection: IP44.
• Class: B.
• Supply filter: F7 / ePM1 70%.
• Extract filter: M5 / ePM10 50%.
• Bypass: internal with actuator.
• Filter pressure switches: included.
• Temperature probes: pre-wired.
• External safety switch: included.
• Power supply: 1/230 V, 50-60 Hz.
• Maximum absorbed power: 0.31 kW.
• Maximum current: approximately 2.1 A.
• Air connections: Ø200 mm.
• Main dimensions: 1120 x 698 x 289 mm.
• Internal insulation: 25 mm mineral wool.
• Weight: approximately 70 kg.
• Minimum standard outdoor temperature: -10 °C.

Compact high-efficiency heat recovery unit for tertiary ventilation

The S&P CAD-COMPACT 500 ECOWATT combines high-efficiency thermal recovery, EC motors, F7/M5 filtration, and an internal bypass in a compact unit designed for horizontal installations. Its nominal airflow of around 440 m³/h at 150 Pa makes it especially suitable for double-flow mechanical ventilation projects in small and medium-sized tertiary spaces.

The ECOWATT version is delivered without integrated control, but with fans, bypass, pressure switches, and probes pre-wired in the electrical cabinet, allowing the installer to complete the regulation according to the project requirements. Installation must be carried out respecting the access conditions for maintenance, condensate drainage, duct connection, and electrical requirements established by Soler & Palau.