Trane RTAC 140-500 ton units (60 Hz) User Manual
RTAC-SVX01F-EN
47
Installation - Mechanical
Important
1.
Additional glycol beyond the recommendations will adversely effect unit perfor-
mance. The unit efficiency will be reduced and the saturated evaporator tempera-
ture will be reduced. For some operating conditions this effect can be significant.
mance. The unit efficiency will be reduced and the saturated evaporator tempera-
ture will be reduced. For some operating conditions this effect can be significant.
2.
If additional glycol is used, then use the actual % glycol to establish the low
refrigerant cutout setpoint.
refrigerant cutout setpoint.
3.
The minimum low refrigerant cutout setpoint allowed is -5 deg F. The minimum is
established by the solubility limits of the oil in the refrigerant.
established by the solubility limits of the oil in the refrigerant.
Specials
The following constitute a special that must be calculated by engineering:
The following constitute a special that must be calculated by engineering:
1.
Freeze inhibitor other than Ethylene Glycol or Propylene Glycol.
2.
Fluid delta T outside the range 4 to 16 deg F.
3.
Unit configuration other than Standard, Standard with extra pass, and Premium.
4.
% Glycol greater than maximum in column in
Special should all be calculated by engineering. The purpose of calculating is to make
sure that design saturation temperature is greater than 3 deg F. Additionally, the calcu-
lation must verify that the fluid freeze point is a minimum of 4 deg. F lower that the
design saturation temperature. The low evaporator temperature cutout will be 4 deg F
below the freeze point or -5 deg F, whichever is greater.
sure that design saturation temperature is greater than 3 deg F. Additionally, the calcu-
lation must verify that the fluid freeze point is a minimum of 4 deg. F lower that the
design saturation temperature. The low evaporator temperature cutout will be 4 deg F
below the freeze point or -5 deg F, whichever is greater.