Tranquility Aluminum Tube Cased Coil (TAC)
R e v. : A u g u s t 2 1 , 2 0 1 8
12
G e o t h e r m a l H e a t i n g a n d C o o l i n g
Figure 6: Air Coil Connection
Add-On Heat Pump Applications
The indoor coil should be located on the supply side of
the furnace to avoid condensation damage to the furnace
heat exchanger for add-on heat pump applications. A high
temperature limit switch should be installed as shown
in Figure 9 just upstream of the coil to de-energize the
compressor any time the furnace is energized to avoid
blowing hot air directly into the coil, elevating refrigerant
pressures during operation. The heat pump will trip out on
high pressure lockout without some method of disengaging
the compressor during furnace operation. Alternatively, some
thermostats with “dual fuel” mode will automatically de-
energize the compressor when second stage (backup) heat
is required.
Air Coil
To obtain maximum performance of a newly manufactured
air coil it should be cleaned before start-up. A 10% solution
of dishwasher detergent and water is recommended for both
sides of the coil. A thorough water rinse should follow.
*An LT2 (low temperature air coil protection) sensor is
available for field installation. Order sensor kit number
S17S0031N12.
Sensing Bulb
IMPORTANT:
DO NOT perform any brazing with the TXV
bulb attached to any line. After brazing operations have been
completed, clamp the TXV bulb securely on the suction line
at the 10 to 2 o’clock position with the strap provided in the
parts bag. Insulate the TXV sensing bulb and suction line
with the provided pressure sensitive insulation and secure
with provided wire ties.
IMPORTANT:
TXV sensing bulb should be located on a
horizontal section of copper suction line, just outside of
coil box. The copper sensing bulb must never be placed
on any aluminum tube as this will result in galvanic
corrosion and eventual failure of the aluminum tube.
Installation
Evacuation
LEAK TESTING - The refrigeration line set must be pressurized
and checked for leaks before evacuating and charging the
unit. To pressurize the line set, attach refrigerant gauges to
the service ports and add an inert gas (nitrogen or dry carbon
dioxide) until pressure reaches 60-90 psig [413-620 kPa]. Never
use oxygen or acetylene to pressure test. Use a good quality
bubble solution to detect leaks on all connections made in the
field. Check the service valve ports and stem for leaks. If a leak
is found, repair it and repeat the above steps. For safety reasons
do not pressurize system above 150 psig [1034 kPa]. System is
now ready for evacuation and charging.
Condensate Drain Tubing
Consult local codes or ordinances for specific requirements.
IMPORTANT:
When making drain fitting connections to the
drain pan, use a thin layer of Teflon paste, silicone or Teflon
tape and install hand tight.
IMPORTANT:
When making drain fitting connections to drain
pan, do not overtighten. Overtightening fittings can split pipe
connections on the drain pan.
•
Install drain lines so they do not block service access
to front of the unit. Minimum clearance of 24 inches [61
cm] is recommended for filter, coil or blower removal and
service access.
• Make sure unit is level or pitched slightly toward primary
drain connection so that water will drain completely from
the pan. (See Figure 7.)
• Do not reduce drain line size less than connection size
provided on condensate drain pan.
• All drain lines must be pitched downward away from the
unit a minimum of 1/8” per foot [11 mm per m] of line to
ensure proper drainage.
• Do not connect condensate drain line to a closed or
open sewer pipe. Run condensate to an open drain or
outdoors.
• The drain line should be insulated where necessary to
prevent sweating and damage due to condensate forming
on the outside surface of the line.
TXV w/Internal
Check Valve
Suction Line
Liquid Line
Bulb
(Must be
Installed and
Insulated)
Equalizer
Line
*LT2
Low Temperature
Air Coil Safety
(Optional)
