Page 9
TSA*H4 SERIES
IMPORTANT
If this unit is being matched with an approved line set or
indoor unit coil which was previously charged with
mineral oil, or if it is being matched with a coil which was
manufactured before January of 1999, the coil and line
set must be flushed prior to installation. Take care to
empty all existing traps. Polyol ester (POE) oils are used
in Lennox units charged with HFC-410A refrigerant.
Residual mineral oil can act as an insulator, preventing
proper heat transfer. It can also clog the expansion
device, and reduce the system performance and
capacity.
Failure to properly flush the system per the instructions
below will void the warranty.
Brazing Connections
Use the procedures outline in figures 8 and 9 for brazing
line set connections to service valves.
IMPORTANT
Polyol ester (POE) oils used with HFC-410A refrigerant
absorb moisture very quickly. It is very important that
the refrigerant system be kept closed as much as
possible. DO NOT remove line set caps or service valve
stub caps until you are ready to make connections.
WARNING
Danger of fire. Bleeding the refrigerant
charge from only the high side may result
in pressurization of the low side shell and
suction tubing. Application of a brazing
torch to a pressurized system may result
in ignition of the refrigerant and oil
mixture - Check the high and low
pressures before applying heat.
WARNING
When using a high pressure gas such as
dry nitrogen to pressurize a refrigeration
or air conditioning system, use a
regulator that can control the pressure
down to 1 or 2 psig (6.9 to 13.8 kPa).
CAUTION
Brazing alloys and flux contain materials which are
hazardous to your health.
Avoid breathing vapors or fumes from brazing
operations. Perform operations only in well-ventilated
areas.
Wear gloves and protective goggles or face shield to
protect against burns.
Wash hands with soap and water after handling brazing
alloys and flux.
IMPORTANT
Connect gauge set low pressure side to vapor line
service valve and repeat procedure starting at
paragraph 4 for brazing the liquid line to service port
valve.
IMPORTANT
Allow braze joint to cool before removing the wet rag
from the service valve. Temperatures above 250ºF can
damage valve seals.
IMPORTANT
Use silver alloy brazing rods with 5% minimum silver
alloy for copper-to-copper brazing. Use 45% minimum
alloy for copper-to-brass and copper-to-steel brazing.
WARNING
Fire, Explosion and Personal Safety
Hazard.
Failure to follow this warning could
result in damage, personal injury or
death.
Never use oxygen to pressurize or
purge refrigeration lines. Oxygen,
when exposed to a spark or open
flame, can cause fire and/or an ex
plosion, that could result in property
damage, personal injury or death.
