Lennox ROOFTOP FLEXY FXK 55, Installation, Operating And Maintenance Manual

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WATER CONDENSING
FLEXYII_WSHP-IOM-1307-E - 14 -
Antifreeze protection
Use glycol/water solution
ADDITION OF GLYCOL IS THE ONLY EFFICIENT WAY TO PROTECT AGAINST FREEZING
The glycol/water solution must be sufficiently concentrated to ensure proper protection and prevent formation of
ice at the lowest outdoor air temperatures expected on an installation. Take precautions when using non
passivated MEG antifreeze solutions (Mono Ethylene Glycol or MPG Mono Propylene Glycol). Corrosion can
occur with these antifreeze solutions with oxygen.
Drain the installation
To enable drainage of the circuit, make sure that drain cocks are installed at all the low points of the circuit.
To drain the circuit, the drain cocks must be opened and an air inlet ensured.
Note : air bleeders are not designed to admit air.
EVAPORATOR FREEZING DUE TO COLD WEATHER CONDITIONS IS NOT COVERED BY LENNOX
WARRANTY.
Minimum water content
The minimum volume of the rooftop water circuit must be determined. If necessary, install a buffer tank. Proper operation of
regulating and safety devices can only be ensured if the volume of water is sufficient.
The theoretical volume of the water loop for a proper air conditioning operation can be calculated using the formulas hereafter:
WATER COOLED FLEXYII RANGE
Vt
à
Minimum water content of the installation
Q
à
Water capacity in kW
N
à
Number of control steps available in the unit
Dt
à
Maximum acceptable temperature rise (Dt = 6°c for an air conditioning application)
Vmini = 86 x Q / (N x Dt)
Unit Size
Number of
stages
Mini Water
Volume (L)
FWH/FWM 085
FWH/FWM 100
FWH/FWM 120
FWH/FWM 150
FWH/FWM 170 2
2
2
3
4 631
781
867
702
627
Victaulic connection assembly instruction
Be careful not to roll or pinch the seal when installing the half-shells. This would cause a leak.
1-Install the bolts and tighten the nuts by hand on them.
2- tighten bolts uniformly passing from one side to the other, until the pads for the bolts are in metal-metal contact. Make sure
the shoulders are well engaged in the grooves.