Unitary products group EF-10, Инструкция по установке

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035-18550-001-A-0902
16 Unitary Products Group
ALTERNATE CHARGING METHODS
If you are starting a unit when the ambient temperature
is higher or lower than those shown in Figure 9, either
of the following methods may be used.
Method 1: Determine the total weight of the refriger-
ant for the total system by adding the
required charge for the outdoor unit, the
indoor unit and the refrigerant lines using
information in Tables 1 (Physical Data)
and 6 (Refrigerant Line Charge). Using the
charging procedures outlined above,
weigh the required amount of refrigerant
charge into the unit.
Method 2: Install a field supplied moisture indicating
sight glass in the liquid line between the fil-
ter-drier and the evaporator coil.
Using the charging procedure outlined
above, charge refrigerant until the mois-
ture indicating sight glass is clear. Add
approximately 1 extra pound of refrigerant
to assure a liquid refrigerant seal at the
expansion valve under all operating condi-
tions. Block the flow of the condenser air, if
necessary, to assure a head pressure of
280 psig during the charging procedure.
NOTE:
The installer should return to the job to verify
the operating charge when the ambient tem-
perature is within the conditions shown in Fig-
ure 9.
BALANCE POINT SETTING
The balance point of a heat pump is the lowest temper-
ature at which the refrigeration system can heat the
building without any supplemental resistance heat.
The balance point is dependent upon -
1. The outdoor design temperature,
2. The building heat loss at the outdoor design tem-
perature, and
3. The heating capacity of the system at the outdoor
design temperature.
Refer to Form 515.41-AD1 to determine balance point.
Refer to Form 690.63-N1V for details regarding the
outdoor ambient balance point control accessory
Model No. 2BP11700224.
FIGURE 8 - REFRIGERANT FLOW DIAGRAM