Air HANDLING UNITS  – PAH

Options and Accessories

The flexible modular design of the PAH units allows various section arrangements according to the task requirement.

This range is capable of air flow rates from 600 l/s (1,200 cfm) to 21,000 l/s (45,000 cfm) in a single piece unit.

Custom designs are available up to 94,000 l/s (200,000 cfm).

All AHU systems

Unit Construction

Structural welded galvanized steel C-channel base with full supporting cross members,
equipped with screwed-in lifting lugs (eye bolts) of suitable loading capacity which are fitted
on a welded bracket to the side of the C-channel

  • 3mm thick for models PAH12 ~ PAH200
  • 6mm thick for PAH250 ~ PAH450
  • The base members are coated with primer sprayed paint
  • Base height is 100mm
  • Base height 140mm and 180mm are available as options
  • Painted base is available as an option

Petra’s AHU frame is constructed of high quality grade extruded metal profiles.  The unit’s rigidity and flexibility are achieved by using Penta-post construction which consists of strong metallic corners joined together by male and female fixtures

The internal cavity for the frame is filled with 0.048g/cm³ density injected foam insulation

  • Double wall G-90 galvanized steel
  • 50mm injected foam, 0.048g/cm³ insulation density as minimum
  • No Metal Through panels along full panel parameter
  • 16-22 gauge painted interior and exterior panels
  • Standard panels are galvanized steel
  • Stainless steel and aluminum panels are optional
  • Each panel shall have a machine applied foam gasket that seals all around its edges
  • Petra paint is certified according to ASTM 117 A&B 5,000 hours salt spray test
  • Painted perforated inner skin is available as optional feature

50mm injected foam, 0.048g/cm³ insulation density as minimum

  • No Metal Through panels along full panel parameter
  • Petra paint is certified according to ASTM 117 A&B 5,000 hours salt spray test
  • Painted steel floor available as option
  • Aluminium tread plate floor available as option

 

 

Double wall G-90 galvanized steel

  • 38mm injected foam, 0.048g/cm³ insulation density as minimum
  • No Metal Through doors along full door parameter
  • 16-22 gauge painted interior and exterior panels
  • Standard panels are galvanized steel
  • Stainless steel and aluminum panels are optional
  • Clip on PVC gasket
  • Minimum two PVC AB Ind handles openable from inside & outside
  • Petra paint is certified according to ASTM 117 A&B 5,000 hours salt spray test
  • Inspection window (rectangular/circular)
  • Access doors that can be opened from inside & outside of the unit
  • One tooled latched handle
  • Heavy duty neoprene type door gasket
  • Door open against pressure (in-swing door)
  • Relief latch for pressure opened doors
  • Stainless steel piano hinges
  • Outdoor installed units are air and water tight and provided with flat roof covers with standing top seams
  • The unit roof cover extended to make rain gutters along the unit perimeter to ensure positive rainwater drainage
  • Gauge 20 (0.9mm) galvanized steel outer skin painted with electrostatic polyester powder coat, oven baked
  • Petra paint is certified according to ASTM 117 A&B 5,000 hours salt spray test
  • Double sloped roof canopy with standing top seams as standard
  • Rain gutters are provided along the full canopy perimeter to ensure positive rainwater drainage
  • All roof canopy components are fully caulked & sealed to prevent any water leakage
  • Roof canopy is coated with weather-proof, polyester powder electrostatic paint, oven-baked
  • Additional rain gutters are provided for access doors/panels (if not covered by rain gutters)
  • Petra paint is certified according to ASTM 117 A&B 5,000 hours salt spray test

Air Mixing

All dampers are made with a rigid anodized aluminum frame and with multi airfoil aluminum blades so as to reduce pressure drop and the sound generated when air passes through the blades.

An opposed blades arrangement is used with virtually no air leakage.

The damper blade’s rotation is achieved by the PVC gear’s rotation

  • Jam seals: flexible metal compression type along control damper sides
  • Blade seals: seal along control damper blade edge
  • Upon request the dampers are supplied with a manually adjustable lever that can be located on either side of the damper
  • Dampers could be linked for motorized operation

This type of damper is designed to pass an air streamaround a coil in order to control the air stream conditions.

Up to 100% air by-pass can be achieved if required

  • The mixing box module combines the incoming outdoor air with the circulated return air from the conditioned space
  • The mixing box is supplied with fresh and return air dampers
  • Exhaust box function is to exhaust some of the circulated air and return the rest to the supply air stream
  • Both mixing or exhaust box dampers are low leakage opposed
  • Aluminum blades type are used, and assembled in aluminum frame
  • Dampers can be operated manually or motorized by an actuator
  • A combination of mixing boxes with panel filters can be provided in one module
  • Economizer section with exhaust box is available

In Economiser operation, the outside air and return air dampers operate to maintain the supply control set point. If the Economiser operation cannot provide enough cooling to satisfy the supply air control set point, mechanical cooling will be energized.

Once mechanical cooling is operating, the outside air damper position is either set at 100% open or at the minimum position set point.

According to the application, the Economiser could contain an exhaust damper function
to exhaust some of the circulated air.  All Economiser dampers are low leakage opposed, aluminum blades type, and they are assembled in an aluminum frame.

These dampers can be operated manually or by an actuator (optional).  A combination of mixing boxes (OA & RA dampers) with panel filters can be provided in one module.

The Economiser also includes hoods for OA and EA damper opening or louvres for EA openings.

Filters

1- Pleated

  • Environment-friendly materials
  • High tensile strength media
  • Rigid construction
  • Maximum temperature up to 90ºC

2- Synthetic

  • A progressively structured filter media made from thermally bonded synthetic fibres
  • Operational temperature up to 130ºC

3- Aluminum

  • Flexibility in shape
  • Low resistance
  • Washable

50mm and 100mm thickness are available

Magnehelic filter gauge, dirty filter switch & pressure taps are available as optional features for all filters

Available for pleated, synthetic & aluminum flat filter types

External flat filter is applicable for PAH 12 to PAH 100. An internal flat filter is used for larger models

50mm and 100mm thickness are available

Magnehelic filter gauge, dirty filter switch & pressure taps are available as optional features for all filters

Available for pleated, synthetic & aluminum flat filter types.

V-type filters are highly recommended whenever face velocity is to be reduced,

50mm and 100mm thickness are available

Magnehelic filter gauge, dirty filter switch & pressure taps are available as optional features for all filters

  • Used when higher level of filtration than flat or V-types is required
  • Made of synthetic media
  • Mechanically strong with high absorption resistance
  • Excellent performance in high moisture conditions
  • Low initial pressure drop
  • High dust holding capacity
  • Long service life
  • Maximum operating temperature 60ºC

50mm and 100mm thickness are available

Magnehelic filter gauge, dirty filter switch & pressure taps are
available as optional features for all filters

  • Used in clean room applications to achieve very high efficiency of filtration
  • Less costly installation space is necessary
  • Energy Saving
  • Long service life
  • Maximum operating temperature up to 90ºC

Coils

  • Petra’s AHU coils are manufactured in-house in our coil manufacturing facility
  • Coils are designed to deliver their respective duties at optimum performance under all design conditions
  • Coils are tested at 3,100 kPa air pressure under water
  • They also undergo dry chemical cleaning after coil manufacturing for optimum system cleanliness
  • Airtight gaskets are used where coil pipes exit the unit casing. The sealing around the coil prevents air by-pass
  • As a standard in the water coils, a drainage connection is attached to the coil, and an air vent is located in the highest point of the coil to release the air from the coil

Tubes

  • 9.5 mm seamless copper
  • Mechanically expanded into full length fin collars
  • Copper return bends stub connections are brazed into expanded tube ends using brazing alloy are available up to 12 rows

Fins

  • Aluminum alloy fins configured sinusoidal type fins
  • 8 to 16 fins per inch available

Distributor

  • Seamless copper tube
  • Distributor individually sized to coils to minimize pressure drop

Coil Casing (coil end plate)

  • Mill galvanized sheet metal with full slotted flanges for convenient mounting
  • Stainless steel coil casing (Optional)

Copper tubes, aluminum fins coil
Coils are manufactured from seamless copper tubes mechanically expanded into aluminum fins, with type-L, heavy wall, seamless copper tubes for the coil headers. The evaporator coils are hydrostatic pressure tested in accordance with the UL 1995 -2000 standard. All coils are air pressure tested by dry air up to 3,100 kPa under water.

They also undergo dry cleaning after manufacturing for optimum system cleanness.

Copper tubes, copper fins coil
Coils are manufactured from seamless copper tubes mechanically expanded into copper fins, with type-L, heavy wall, seamless copper tubes for the coil headers. The condenser coils are hydrostatic pressure tested in accordance with the UL 1995 -2000 standard. All coils are air pressure tested by dry air up to 3,100 kPa under water.

They also undergo dry cleaning after manufacturing for optimum system cleanness.

Polyurethane pre-coating (for aluminum fins)
A water based organic type pre-coated fin designed to give better retained performances
compared to typical organic type. The topcoat is made of hydrophilic resin of polyvinyl alcohol mix with hydrophilic lubricants. It provides a better level of retained as well as improvement in the area of surface friction to help lengthen the life span of a punch dies. Paint is certified as per ASTM 117 A&B up to 3000 hours salt spray test

Polyurethane Post-coating (for aluminum & copper fins)
Aliphatic acrylic polyurethane type, with high gloss finish with exceptional weathering performance characteristics. Used extensively in virtually all industrial markets, 134 VOC provides a smooth, durable finish that has superior resistance to corrosion, abrasion and chemical exposure. Paint is certified as per ASTM 117 A&B up to 3000-4000 hours salt spray test

Coil connections can be provided on either right or left hand side facing air return.

 

 

Drain pan is supplied as standard under the cooling coil (chilled water or DX). Drain pan is made of 1.5mm thick painted galvanized steel with a connection from side. The drain pan is mounted on a channel base insulated with 6.4mm closed cell foam insulation class “O” to prevent condensation.  The drain pan is single sloped drain pan. Drain trap design.

Options:

  • Stainless steel drain pan
  • Drain pan connection from both sides
  • Double sloped drain pan
  • Double skin drain pan with gauge 16 outer with 1.5mm thickness
  • Threaded male/female design

Fans

Structural welded galvanized steel C-channel base with full supporting cross members, equipped with screwed-in lifting lugs (eye bolts) of suitable loading capacity which are fitted on a welded bracket to the side of the C-channel

  • 3mm thick for models PAH12 ~ PAH200
  • 6mm thick for PAH250 ~ PAH450
  • The base members are coated with primer sprayed paint
  • Base height is 100mm
  • Base height 140mm and 180mm are available as options
  • Painted base is available as an option

Petra’s AHU frame is constructed of high quality grade extruded metal profiles.  The unit’s rigidity and flexibility are achieved by using Penta-post construction which consists of strong metallic corners joined together by male and female fixtures

The internal cavity for the frame is filled with 0.048g/cm³ density injected foam insulation

  • Double wall G-90 galvanized steel
  • 50mm injected foam, 0.048g/cm³ insulation density as minimum
  • No Metal Through panels along full panel parameter
  • 16-22 gauge painted interior and exterior panels
  • Standard panels are galvanized steel
  • Stainless steel and aluminum panels are optional
  • Each panel shall have a machine applied foam gasket that seals all around its edges
  • Petra paint is certified according to ASTM 117 A&B 5,000 hours salt spray test
  • Painted perforated inner skin is available as optional feature

50mm injected foam, 0.048g/cm³ insulation density as minimum

  • No Metal Through panels along full panel parameter
  • Petra paint is certified according to ASTM 117 A&B 5,000 hours salt spray test
  • Painted steel floor available as option
  • Aluminium tread plate floor available as option

 

 

Double wall G-90 galvanized steel

  • 38mm injected foam, 0.048g/cm³ insulation density as minimum
  • No Metal Through doors along full door parameter
  • 16-22 gauge painted interior and exterior panels
  • Standard panels are galvanized steel
  • Stainless steel and aluminum panels are optional
  • Clip on PVC gasket
  • Minimum two PVC AB Ind handles openable from inside & outside
  • Petra paint is certified according to ASTM 117 A&B 5,000 hours salt spray test
  • Inspection window (rectangular/circular)
  • Access doors that can be opened from inside & outside of the unit
  • One tooled latched handle
  • Heavy duty neoprene type door gasket
  • Door open against pressure (in-swing door)
  • Relief latch for pressure opened doors
  • Stainless steel piano hinges

Heat Recovery

All dampers are made with a rigid anodized aluminum frame and with multi airfoil aluminum blades so as to reduce pressure drop and the sound generated when air passes through the blades.

An opposed blades arrangement is used with virtually no air leakage.

The damper blade’s rotation is achieved by the PVC gear’s rotation

  • Jam seals: flexible metal compression type along control damper sides
  • Blade seals: seal along control damper blade edge
  • Upon request the dampers are supplied with a manually adjustable lever that can be located on either side of the damper
  • Dampers could be linked for motorized operation

This type of damper is designed to pass an air stream around a coil in order to control the air stream conditions.

Up to 100% air by-pass can be achieved if required

  • The mixing box module combines the incoming outdoor air with the circulated return air from the conditioned space
  • The mixing box is supplied with fresh and return air dampers
  • Exhaust box function is to exhaust some of the circulated air and return the rest to the supply air stream
  • Both mixing or exhaust box dampers are low leakage opposed
  • Aluminum blades type are used, and assembled in aluminum frame
  • Dampers can be operated manually or motorized by an actuator
  • A combination of mixing boxes with panel filters can be provided in one module
  • Economizer section with exhaust box is available

In Economiser operation, the outside air and return air dampers operate to maintain the supply control set point. If the Economiser operation cannot provide enough cooling to satisfy the supply air control set point, mechanical cooling will be energized.

Once mechanical cooling is operating, the outside air damper position is either set at 100% open or at the minimum position set point.

According to the application, the Economiser could contain an exhaust damper function
to exhaust some of the circulated air.  All Economiser dampers are low leakage opposed, aluminum blades type, and they are assembled in an aluminum frame.

These dampers can be operated manually or by an actuator (optional).  A combination of mixing boxes (OA & RA dampers) with panel filters can be provided in one module.

The Economiser also includes hoods for OA and EA damper opening or louvres for EA openings.

In Economiser operation, the outside air and return air dampers operate to maintain the supply control set point. If the Economiser operation cannot provide enough cooling to satisfy the supply air control set point, mechanical cooling will be energized.

Once mechanical cooling is operating, the outside air damper position is either set at 100% open or at the minimum position set point.

According to the application, the Economiser could contain an exhaust damper function
to exhaust some of the circulated air.  All Economiser dampers are low leakage opposed, aluminum blades type, and they are assembled in an aluminum frame.

These dampers can be operated manually or by an actuator (optional).  A combination of mixing boxes (OA & RA dampers) with panel filters can be provided in one module.

The Economiser also includes hoods for OA and EA damper opening or louvres for EA openings.

In Economiser operation, the outside air and return air dampers operate to maintain the supply control set point. If the Economiser operation cannot provide enough cooling to satisfy the supply air control set point, mechanical cooling will be energized.

Once mechanical cooling is operating, the outside air damper position is either set at 100% open or at the minimum position set point.

According to the application, the Economiser could contain an exhaust damper function
to exhaust some of the circulated air.  All Economiser dampers are low leakage opposed, aluminum blades type, and they are assembled in an aluminum frame.

These dampers can be operated manually or by an actuator (optional).  A combination of mixing boxes (OA & RA dampers) with panel filters can be provided in one module.

The Economiser also includes hoods for OA and EA damper opening or louvres for EA openings.

In Economiser operation, the outside air and return air dampers operate to maintain the supply control set point. If the Economiser operation cannot provide enough cooling to satisfy the supply air control set point, mechanical cooling will be energized.

Once mechanical cooling is operating, the outside air damper position is either set at 100% open or at the minimum position set point.

According to the application, the Economiser could contain an exhaust damper function
to exhaust some of the circulated air.  All Economiser dampers are low leakage opposed, aluminum blades type, and they are assembled in an aluminum frame.

These dampers can be operated manually or by an actuator (optional).  A combination of mixing boxes (OA & RA dampers) with panel filters can be provided in one module.

The Economiser also includes hoods for OA and EA damper opening or louvres for EA openings.

Other Section

1- Pleated

  • Environment-friendly materials
  • High tensile strength media
  • Rigid construction
  • Maximum temperature up to 90ºC

2- Synthetic

  • A progressively structured filter media made from thermally bonded synthetic fibres
  • Operational temperature up to 130ºC

3- Aluminum

  • Flexibility in shape
  • Low resistance
  • Washable

50mm and 100mm thickness are available

Magnehelic filter gauge, dirty filter switch & pressure taps are available as optional features for all filters

Available for pleated, synthetic & aluminum flat filter types

External flat filter is applicable for PAH 12 to PAH 100. An internal flat filter is used for larger models

50mm and 100mm thickness are available

Magnehelic filter gauge, dirty filter switch & pressure taps are available as optional features for all filters

Available for pleated, synthetic & aluminum flat filter types.

V-type filters are highly recommended whenever face velocity is to be reduced,

50mm and 100mm thickness are available

Magnehelic filter gauge, dirty filter switch & pressure taps are available as optional features for all filters

  • Used when higher level of filtration than flat or V-types is required
  • Made of synthetic media
  • Mechanically strong with high absorption resistance
  • Excellent performance in high moisture conditions
  • Low initial pressure drop
  • High dust holding capacity
  • Long service life
  • Maximum operating temperature 60ºC

50mm and 100mm thickness are available

Magnehelic filter gauge, dirty filter switch & pressure taps are
available as optional features for all filters

  • Used in clean room applications to achieve very high efficiency of filtration
  • Less costly installation space is necessary
  • Energy Saving
  • Long service life
  • Maximum operating temperature up to 90ºC
  • Used in clean room applications to achieve very high efficiency of filtration
  • Less costly installation space is necessary
  • Energy Saving
  • Long service life
  • Maximum operating temperature up to 90ºC
  • Used in clean room applications to achieve very high efficiency of filtration
  • Less costly installation space is necessary
  • Energy Saving
  • Long service life
  • Maximum operating temperature up to 90ºC
  • Used in clean room applications to achieve very high efficiency of filtration
  • Less costly installation space is necessary
  • Energy Saving
  • Long service life
  • Maximum operating temperature up to 90ºC

Optional Accessories

  • Petra’s AHU coils are manufactured in-house in our coil manufacturing facility
  • Coils are designed to deliver their respective duties at optimum performance under all design conditions
  • Coils are tested at 3,100 kPa air pressure under water
  • They also undergo dry chemical cleaning after coil manufacturing for optimum system cleanliness
  • Airtight gaskets are used where coil pipes exit the unit casing. The sealing around the coil prevents air by-pass
  • As a standard in the water coils, a drainage connection is attached to the coil, and an air vent is located in the highest point of the coil to release the air from the coil

Tubes

  • 9.5 mm seamless copper
  • Mechanically expanded into full length fin collars
  • Copper return bends stub connections are brazed into expanded tube ends using brazing alloy are available up to 12 rows

Fins

  • Aluminum alloy fins configured sinusoidal type fins
  • 8 to 16 fins per inch available

Distributor

  • Seamless copper tube
  • Distributor individually sized to coils to minimize pressure drop

Coil Casing (coil end plate)

  • Mill galvanized sheet metal with full slotted flanges for convenient mounting
  • Stainless steel coil casing (Optional)

Copper tubes, aluminum fins coil
Coils are manufactured from seamless copper tubes mechanically expanded into aluminum fins, with type-L, heavy wall, seamless copper tubes for the coil headers. The evaporator coils are hydrostatic pressure tested in accordance with the UL 1995 -2000 standard. All coils are air pressure tested by dry air up to 3,100 kPa under water.

They also undergo dry cleaning after manufacturing for optimum system cleanness.

Copper tubes, copper fins coil
Coils are manufactured from seamless copper tubes mechanically expanded into copper fins, with type-L, heavy wall, seamless copper tubes for the coil headers. The condenser coils are hydrostatic pressure tested in accordance with the UL 1995 -2000 standard. All coils are air pressure tested by dry air up to 3,100 kPa under water.

They also undergo dry cleaning after manufacturing for optimum system cleanness.

Polyurethane pre-coating (for aluminum fins)
A water based organic type pre-coated fin designed to give better retained performances
compared to typical organic type. The topcoat is made of hydrophilic resin of polyvinyl alcohol mix with hydrophilic lubricants. It provides a better level of retained as well as improvement in the area of surface friction to help lengthen the life span of a punch dies. Paint is certified as per ASTM 117 A&B up to 3000 hours salt spray test

Polyurethane Post-coating (for aluminum & copper fins)
Aliphatic acrylic polyurethane type, with high gloss finish with exceptional weathering performance characteristics. Used extensively in virtually all industrial markets, 134 VOC provides a smooth, durable finish that has superior resistance to corrosion, abrasion and chemical exposure. Paint is certified as per ASTM 117 A&B up to 3000-4000 hours salt spray test

Coil connections can be provided on either right or left hand side facing air return.

 

 

Drain pan is supplied as standard under the cooling coil (chilled water or DX). Drain pan is made of 1.5mm thick painted galvanized steel with a connection from side. The drain pan is mounted on a channel base insulated with 6.4mm closed cell foam insulation class “O” to prevent condensation.  The drain pan is single sloped drain pan. Drain trap design.

Options:

  • Stainless steel drain pan
  • Drain pan connection from both sides
  • Double sloped drain pan
  • Double skin drain pan with gauge 16 outer with 1.5mm thickness
  • Threaded male/female design

Drain pan is supplied as standard under the cooling coil (chilled water or DX). Drain pan is made of 1.5mm thick painted galvanized steel with a connection from side. The drain pan is mounted on a channel base insulated with 6.4mm closed cell foam insulation class “O” to prevent condensation.  The drain pan is single sloped drain pan. Drain trap design.

Options:

  • Stainless steel drain pan
  • Drain pan connection from both sides
  • Double sloped drain pan
  • Double skin drain pan with gauge 16 outer with 1.5mm thickness
  • Threaded male/female design