AHU-Guideline 01 General requirements for Air Handling Units PDF

Preview

Summary

AHU-Guideline 01 General requirements for Air Handling Units Issue August 2011 For the latest version please refer to the Internet. Incl. new VDI 3803 Sheet 1 new DIN EN 1886 Amendment to DIN EN 13053 Energy efficiency classes A+, A, B Herstellerverband Raumlufttechnische Geräte e. V. German AHU Man...

Description

AHU-Guideline 01

General requirements for Air Handling Units Issue August 2011 For the latest version please refer to the Internet.

Incl. new VDI 3803 Sheet 1 new DIN EN 1886 Amendment to DIN EN 13053 Energy efficiency classes A+, A, B

Herstellerverband Raumlufttechnische Geräte e. V. German AHU Manufacturer Association

AHU Guideline 01

Foreword With this AHU Guideline 01 ‘General requirements for Air Handling Units the Herstellerverband Raumlufttechnische Geräte e.V. (German AHU Manufacturers Association) provides the basis for high quality standards. This guideline contains all relevant standards and, in the case of incongruent statements and gaps in the provisions, defines the current state of technology. The AHU Guideline 01 is a logical development that has evolved from the ‘Güte- und Prüfbestimmungen’ for ‘RAL-Geräte’ (Quality and Testing Guidelines for RAL-approved units) published by us for the first time in 1995. It provides uniform, comparable criteria and thereby is a reliable guide for selecting standard-compliant and energy-efficient air handling equipment that meets hygiene requirements. The introduction of energy classes A+, A and B takes into account recent legislation that requires clear and comprehensible statements to be made regarding energy efficiency. The guideline will be supplemented and brought up to date to reflect advances in technology.

Bietigheim-Bissingen, August 2011 Herstellerverband Raumlufttechnische Geräte e.V. Reproduced with permission of the DIN, Deutsches Institut für Normung e.V. (German Standardisation Institute). DIN standards should only be applied in their latest version, which can be obtained from Beuth Verlag GmbH, Burggrafenstraße 6, 10787 Berlin. This AHU guideline can be downloaded free of charge from the homepage of the Herstellerverband Raumlufttechnische Geräte e.V. (www.rlt-geraete.de) Table of contents 1. 2. 3. 4. 4.1 4.2 5. 5.1 5.2 5.2 5.3 5.4 5.5 5.6 5.7 5.8 5.9 5.10 6.

2

Purpose and scope ...................................................................................................................................................... 3 Legislation, regulations, standards, guidelines and data sheets .................................................................................. 3 Terms and definitions................................................................................................................................................... 3 Energy efficiency classes............................................................................................................................................. 4 Specific Fan Power (SFP)............................................................................................................................................ 4 Energy efficiency classes A+, A and B......................................................................................................................... 4 AHU (air handling unit) requirements........................................................................................................................... 5 Casing.......................................................................................................................................................................... 5 Air connections / air openings ...................................................................................................................................... 8 Air connections / air openings (continued) ................................................................................................................... 9 Dampers and mixing sections ...................................................................................................................................... 9 Filter section............................................................................................................................................................... 10 Heat recovery section ................................................................................................................................................ 12 Air heating and cooling section .................................................................................................................................. 13 Sound Attenuator section........................................................................................................................................... 15 Humidifier section ...................................................................................................................................................... 16 Fan section ................................................................................................................................................................ 18 additional equipment and documentation .................................................................................................................. 20 Appendix.................................................................................................................................................................... 22

AHU Guideline 01

1. Purpose and scope This guideline applies to all Air Handling Unit (AHU) and requirements for its construction. An AHU is any part of a ventilation / air conditioning system in accordance with DIN EN 13053. This guideline comments on the energy, hygiene and mechanical properties of AHU’s. In this guideline, the Herstellerverband Raumlufttechnische Geräte e.V. provides an overview of the state of the art in air technology. Where standards and guidelines do not make clear statements on certain issues and only make recommendations or provide classifications, this AHU guideline includes detailed provisions. This AHU Guideline 01 is intended as a guide for investors, users, architects, planners, installers, servicers, maintenance companies and manufacturers in order to ensure that AHU’s equipment reflects state-of-the-art in air technology. This AHU Guideline 01 does not contain any information on special explosion protection requirements or maintaining functionality of AHU’s when used for smoke extraction. These topics are dealt with in AHU Guideline 02 and 04. 2. Legislation, regulations, standards, guidelines and data sheets The following standards and guidelines were taken into consideration for the purpose of compiling this AHU guideline. – VDI 3803 (February 2010) Air-conditioning systems Structural and technical principles – VDI 3803 sheet 5 (draft 2011) Heat recovery systems in AHU-plants – VDI 6022 sheet 1 (April 2006) Hygienic requirements for ventilating and air-conditioning systems and air-handling units – DIN EN 1886 (July 2009) Mechanical properties and measuring methods – DIN EN 13053 (November 2007) with amendment (2011) Capacity Data – DIN EN 13779 (September 2007) General basics and requirements – DIN 1946 part 4 (December 2008) Ventilation and air conditioning systems in hospitals – DIN 1751 (January 1999) Ventilation for buildings – Air terminal devices – Aerodynamic testing of dampers and valves – DIN EN 13501 Part 1 (May 2007) Fire classification of construction products and building elements Part 1: Classification using data from reaction to fire tests – RLT 01 general requirements for Air Handling Units AHU

General requirements

Mechanical Performance

Rating and performance data

DIN EN 13053

DIN EN 1886

DIN EN 13053 DIN EN 13053

DIN EN 13779

DIN 1751

DIN EN 13779 VDI 6022

VDI 3803

DIN 13501/1

RLT 01

DIN 1946/4

RLT 01

RLT 01

VDI 3803/5

RLT 01

3

Hygiene requirements

3. Terms and definitions Unit with increased hygiene requirements: Unit for which the general requirements in the standards with respect to hygiene of AHU equipment are not sufficient. This may be AHU equipment for areas such as hospitals, clinics, doctors’ surgeries with operating theatre, outpatient operating centres, facilities for the preparation of medical products, production of medicines in chemists and in the pharmaceutical industry. Unit with other functions: Units with other thermodynamic functions, other than air heating, such as air humidification, air dehumidification, air cooling etc. Weatherproof Units: Uits for stationing in the open without additional housings or shelter from buildings. Accessible (walk-in) Units: units from a clear internal height von 1.6 m. Coating: Hot-dip galvanized steel sheeting with powder coating or 2-coat wet painted with primer and top coat (minimum 60 µm) or with continuous coating (minimum 25 µm) or materials with corrosion protection class III in accordance with DIN 55928-8. Access doors: Doors have hinges and a maximum of 3 locks. Access panels: Inspection door are metal cover sheets fixed with metric internal or external hexagon screws or Torx screws or toggle closure. Screws with slot or crosshead operation or tapping screws are not permissible for inspection covers. Tubular rivets: Tubular rivets are rivets with a mandrel that is completely removed after setting the rivet, leaving a hole through the rivet. Only those rivets are permissible on which the mandrel is mechanically locked after setting, which means that it cannot fall out. Rivets have to be splash-proof. The mandrel of the rivet must not protrude from the rivet head after setting (but it may break at a lower point). Internal air temperature: In order to determine the internal air temperature where the external air is sucked in via a mixing chamber, the entry temperature of the pre-heater is used. Drainage properties of condensate tray: condensate tray must have a slope to all sides and have a drain. Draining is considered sufficient where any water remaining due to surface tension can be dried off completely by running the system dry. This requirement is deemed to have been met when, after adding 5 l of water 2 for each 1 m of tray base area, at least 95% of the water will drain away within 10 minutes. Grooves and indents: Construction-related indentations should be avoided or filled. An exception are indentations owing to radii of rolled steel sections, as sealing can only be applied outside the radii. Where the base has no grooves (e.g. owing to sealing rubber) it is not necessary to do any filling. High-performance cooler: Cooling coil with a pressure loss of more than 200 Pa.

AHU Guideline 01

4. Energy efficiency classes 4.1 Specific Fan Power (SFP) Until September 2007 no definition exists of energy efficiency of AHU equipment, but only for complete AHU systems which consist of AHU units and the associated ducting for the various functions. DIN EN 13779 ‘Ventilation for non-residential buildings; performance requirements for ventilation and room conditioning systems’ describes Specific Fan Power (SFP) in the context of energy consumption. DIN EN 13779 describes seven classes of SFP (section 6).

PSFP = PINPUT / q v 3

PSFP [W/(m /s)] Specific Fan Power PINPUT [W] Electric power input 3 qv [m /s] Nominal air volume flow When assuming a system efficiency rating of 0.60 it is possible to calculate the approximate overall pressure increase of the fan.

∆p fan = PSFP ⋅ ηtotal ∆pfan [Pa] Overall fan pressure increase 3 PSFP [W/(m /s)]Specific Fan Power ηtotal [-] System efficiency rating fan/motor/drive The pressure increase available has to overcome both the pressure drop of the components in the unit (internal) as well as that of the duct system (external). Since no quantified data have been given for the pressure drop of the duct system and this is not within the unit manufacturer’s sphere of responsibility, the SFP values are not suitable for evaluating the energy efficiency of an air handling unit.

4.2 Energy efficiency classes A+, A and B The energy efficiency of a AHU is primarily affected by the air velocity within the unit, the electric power input of the fan motor in relation to air volume flow and pressure increase as well as the quality of the heat recovery in relation to the heat efficiency and pressure drop. Standard EN 13053 ‘Ratings and performance of air handling units’ contains definitions of air velocity classes ranging from V1 to V9 and heat recovery classes from H1 to H6 and electrical power classes from P1 to P 7. The classes are assigned to the air handling units according to their complexity. The efficiency classes for air handling units combine the velocity classes, the electrical power input and heat recovery efficiency into one simple, clear and checkable indicator. This gives engineers, system providers and operators clear and reliable selection criteria to ensure they are using equipment that optimises energy use. The manufacturer can only mark AHU with an energyefficiency class acc. to this guideline if these have been produced with approved and certified components (heat recovery system / fans). AHU which cannot be equipped with a heat recovery system (for example only air outlet units, pure recirculating air units or air inlet units) can be marked with the efficiency class even without installation of a heat recovery system. Combined exhaust and supply necessarily need a heat recovery system in order to be able to be marked. If an AHU`s fulfils all relevant criteria of this guideline as well as an energy efficiency class A+, A and B and this is checked by TÜV-Süd and is supervised by a permanent certification by TÜV-Süd, the manufacturer is entitled to refer to fulfilment of energy efficiency classes A+, A and B and to use the label shown below for the respective equipment.

Criteria / efficiency classes

A+

A

B

Velocity classes of Units: - without thermodynamic air treatment - with air heating - with other functions

V5 V4 V2

V6 V5 V3

V7 V6 V5

Electrical power input PINPUT max ⋅ Factor

P2

P3

P4

Table A9

Heat recovery classes

H1

H2

H3

Table A10

4

Section 6 appendix Table A8

AHU Guideline 01

5. AHU (air handling unit) requirements 5.1 Casing Table 1: General requirements No Requirements

Standard

Supporting standards VDI 3803/1-5.1 DIN EN 13779-A.7

Surfaces and materials 01

Double-skinned panels with sandwiched insulation (including where frame insulated)

DIN EN 13053-6.2

02

Thermal insulation fitted without cavities

RLT 01

03

The use of single-skin plastic panels for components in contact with the air, e.g. in heat exchangers, is not permitted owing to fire risk and hygiene considerations.

RLT 01

04

Insulation material building material class A1 or A2-s1 d0. Exception: Combustible materials building material class A2, B, C-s3 d2 are admissible if unit is separated to room by fire and smoke protection flap. For coatings thickness ≤ 0,5 mm materials E-d2 admissible

DIN EN 1886-10 DIN EN 13501/1

VDI 3803/1-5.1

05

Minimising combustible materials1)

DIN EN 1886-10

VDI 3803/1-4.4.1

06

Abrasion resistant, emissions free, odourless material non-metabolsable by microorganisms. Do not use seals that absorb moisture or provide a nutrient substrate for micro-organisms.

DIN EN 13053-6.2

VDI 3803/1-5.1 VDI 6022-3.5 VDI 6022-4.1.1 DIN 1946/4-6.1.2 DIN 13779-A.14

07

Interior wall surfaces smooth and without any open adsorptive areas. Porous materials in VDI 6022-4.1.1 the air flow (except sound absorbers) are not permitted.

DIN EN 13053-6.2 VDI 3803/1-5.1 DIN 1946/4-6.1.2

08

Surface characteristics internal and external (incl. base frame) at least hot-dip galvanized DIN EN 13053-6.2 steel sheeting. Inner skin of components immediately downstream of the humidifier to be hot-dip galvanized and painted/coated (section 3).

VDI 3803/1-5.1 VDI 3803/1-4.4.1

Casing indicator values 09

Casing indicator values have to be identified with the extension (R) for real units and (M) for model box.

DIN EN 1886-4

10

Mechanical strength class D2 (R) (section 6)

VDI 3803/1-5.1

DIN EN 1886-5 DIN 1946/4-6.5.3

11

Casing air leakage class L3 (R) (section 6) Permitted overall leakage max. 2% of the nominal volume flow.

DIN EN 13779-A.8.2 VDI 3803/1-5.1

DIN EN 1886-6.1.1

12

Filter bypass leakage filter class F9 max. 0.5% filter class F8 max. 1.0% filter class F7 max. 2.0% filter class F6 max. 4.0% filter class G1-F5 max. 6.0%

DIN EN 1886-7.1.2

13

Thermal transmittance (section 6) T5 (M): units without thermodynamic air treatment T4 (M): units with air heating and other functions

VDI 3803/1-5.1

DIN EN 1886-8.2.1

14

Thermal bridging factor for suction intake chamber and downstream parts of casing (section 6) TB3 (M) when internal air temperature < -7 °C TB4 (M) when internal air temperature -7 °C to + 5 °C

VDI 3803/1-5.1

DIN EN 1886-8.2.2 DIN 1946/4-6.5.3

15

Thermal bridging factor for cooling components and downstream parts of casing (section 6) TB3 (M) when internal air temperature < 7 °C TB4 (M) when internal air temperature 7 °C to +13 °C

VDI 3803/1-5.1

DIN EN 1886-8.2.2 DIN 1946/4-6.5.3

16

Sound insertion loss De (M) has to be stated for 125 Hz to 8000 Hz.

VDI 3803/1-5.1

DIN EN 1886-9.5

1)

5

Combustible materials are inadmissible for units with air temperatures of 85 °C or if combustible materials can settle. Low quantities (sealing, handle, store, measuring device, thermal decouplings, covers) of combustible materials are admissible.

AHU Guideline 01

Continuation of table 1: General requirements No Requirements

Standard

Supporting standard

Access doors and access panels 17

For casing parts with a mandatory thermal bridging factor TB3 (M) or better, the sight glass has to be double-glazed; also, the respective framing must not form an additional thermal bridge.

VDI 3803/1-5.1

18

Up to a clear internal unit height of 800 mm, removable access panels are permitted; for taller units doors have to be provided (section 3).

VDI 6022-4.3.5

19

Doors to components causing a danger must be openable only with a tool and must bear DIN EN 1886-11 a warning sign showing the danger (for example on fans). If this is not possible, the fan has to be equipped with suction, blow-out and belt protection.

20

Sealing gaskets / paint coating must no get damaged by the door closers over a longer period.

RLT 01

21

Access doors of accessible (walk-in) units must be openable from the inside (section 3).

VDI 3803/1-5.1

22

Protection against injury when opening doors on the positive pressure side. No devices must be used that can be deactivated (e.g. a chain that can be disconnected).

DIN EN 1886-11

VDI 3803/1-5.1

VDI 3803/1-5.1

Further requirements 23

Protection against injury from sharp edges or pointed objects.

DIN EN 13053-6.2

DIN EN 1886-11 VDI 3803/1-5.1

24

All components have to be designed in such a way that they are accessible for maintenance and cleaning through ...