The test conditions

The test conditions for the heat pumps were taken from Table 20 in the standard, brine to water heat pump, average climate and low temperature application. The unit is assumed to be a fixed capacity unit with fixed outlet temperature. The heat pumps in the study where all tested in full load according to EN 14511. For the part load conditions the COP was calculated by using equation 12 in the standard. The test point used for the calculations was the 30°C/35°C point from EN 14511 laboratory data. The capacity and COP at Tbivalent and TOL is set to the maximum, while the COP for the delivered capacity at the different outdoor temperatures is calculated by using equations from the standard prEN14825. The default degradation factor where Cc=0.9 is used.

Air to air heat pumps

Air to air heat pumps The data for SPF calculations regarding air to air heat pumps are taken from the field measurements. There are no laboratory data available for the heat pumps tested in the field study.  
The colder climate is chosen for the calculations, since this climate is similar to the climate where the field installation is. The bivalent operation point of the heat pump is calculated by using SPA3528, which is another model for the calculation of SPF. The bivalent point is 0°C. The operation limit point is set to -20°C

the interpolation

At -7°C the heat pump operates in full load to deliver heat to the house. At +2°C and at +7°C the heat pump operates in part load. COP for part load operation is interpolated by using linear interpolation between existing test points. At +2°C the interpolation is made between full load operation and operation at 47% part load, at +7°C the interpolation is made between part load operation at 50% and 57% of the heat pump capacity. At +12°C the required heat load is so small that the heat pump is assumed to cycle on/off. The capacity of this point is calculated by using equation 11 in the standard. The COP for the bivalent point is interpolated from test points in full load operation at +2°C and -7°C

Constant Air Volume

Constant Air Volume System: An air-handling system
involving a continuous level of airflow.
Contact Vacuum: A Collection Device, usually portable,
that uses a nylon brush nozzle attached to the end of its
inlet air hose. The brush head is applied directly to a
surface for cleaning.
Containment Area: An engineered space within a work
area designed to control the migration of contaminants
to adjacent areas during assessment or cleaning
procedures.
Contaminant: Any substance not intended to be present
that is located within the HVAC system.
Converging 45 Degree Cut: Applies to the angle of the
cut when removing a section of ductboard to create an
opening. Provides for resealable fit when re-installing
the section for closure (sometimes referred to as a
“pumpkin cut”).

Hinged -

Hinged - fabricated door and doorframe attached
together with a hinge.
Sandwich - two-part closure device in which the two
sides are mechanically fastened together on both
sides of the duct wall at the perimeter of the service
opening.
Spin Door - round access door and door frame
installed by spinning the door frame into a round
opening.
Ductwork: A system of passageways for distribution and
extraction of air, excluding plenums not installed in
accordance with SMACNA Standards (See ASHRAE
Terminology of Heating, Ventilation, Air Conditioning &
Refrigeration, 1991).
EPA: United States Environmental Protection Agency.
Flame Spread Index: The Flame Spread Index refers to
the sustained combustion classification of a material as
listed in NFPA 255, Standard Method of Test of Surface
Burning Characteristics of Building Materials.

Accumulators should

Accumulators should be possible to include in the model.
 A model must contain clear system boundaries for what is to be included in the calculations and how measurements are performed. As a basis, the system boundaries presented in the SEPEMO project [12] is recommended.
 The model must be transparent so it is possible to follow and understand the calculations. The studied models all contain parts that are more or less transparent. For example how the estimation of the number of equivalent heating hours is performed is not shown in any method.

Crossbreak:

Crossbreak: Diagonal bends made in metal panels to
increase rigidity and decrease flexibility.
Debris: Non-adhered substances not intended to be
present within the HVAC system.
DOP Testing: The percentage removal of 0.3 micrometer
particles of dioctylphthalate (DOP) or equivalent used to
rate high-efficiency air filters, those with efficiencies
above 98%.
Double Wall Duct: Sheet metal duct usually constructed
with an inner perforated liner sandwiching fibrous glass
insulation.
Duct Access Door: Fabricated metal barrier (hatch) by
which a service opening is accessed or closed.
Designed for permanent installation. May be available
pre-fabricated in a variety of sizes and configurations.
Most utilize cam locks for securing the removable door
from the permanently installed doorframe. Types of
Duct Access Doors are listed below: