Delfield Specification Line GA Series, Original Instructions Service Manual

Page: 61 / 104

Part Number GA_SM 08/18 61
Section 8 Refrigeration
Properties of R-290 (Propane)
• R-290 is an alternative (not drop in replacement) for
most commonly used refrigerants
• Special care has to be taken with R-290 because of the
flammability of propane
• R-290 (propane) units are equipped with a yellow
warning label
Avoiding Ignition
• Make sure the capacitors are discharged
• Use caution when working on “live” electrical
components and wiring
• Make sure the unit is grounded and the ground does
not break
• Ensure that the casings on electrical components are
not cracked or broken when charging or recovering
refrigerant
• Replace components with factory specified
components. Other components could result in ignition
of refrigerant in the ambient from a leak
General Safety Precautions When Working With R-290
• Technicians must be instructed on the correct service
procedures with R-290
• Working within confined spaces should be avoided
• No flammable materials are stored in the work area
• No ignition sources are present anywhere in the 35’
work area
• Fire extinguishing equipment is available within the
immediate area
• The work area is properly ventilated before working on
the equipment
• Gas detectors should be present and operating to warn
workers of concentrations of flammable refrigerants
• Only refrigerant handling and other service equipment
designed for use with flammable refrigerants should be
used when working on R-290 systems
Sources of Ignition & Avoiding Ignition
Sparks
Electrical terminals including capacitor terminals must
be tightened and secured against loosening. Wires must
be insulated to prevent shorting and sparking. Electrical
motors must be brush-less.
Open Flames
• R-290 equipment should be positioned at a safe
distance from open flames
• R-290 equipment should be positioned so that there is
always good air gaps around all sides of the equipment
• R-290 equipment should be installed in a well ventilated
space
Hot Surfaces
R-290 equipment should be installed where leaked
refrigerant will not be exposed to any surfaces exceeding
842°F (auto-ignition temperature).
90% air / 10% propane mixture is required for ignition