Greenheck DG/DGX Pilot Ignition (470651_IOM) - Manual (Page 12)

4. Install the Liquid Line and Thermal
Expansion Valve (TXV) (by others)
Liquid line openings vary by coil size and
circuiting and are field-supplied. Follow the TXV
recommendations for installation to avoid damaging
the valve. If the valve is externally equalized, use a
tubing cutter to cut off the plugged end of the factory
installed equalizer line. Use a de-burring tool to
remove any loose metal from the equalizer line and
attach it to the TXV. If the valve is internally equalized,
the factory-installed equalizer line can be left as is
5. Mount the Remote Sensing Bulb
(by others)
The expansion valve’s remote sensing bulb should be
securely strapped to the horizontal run of the suction
line at the 3 or 9 o’clock position and insulated.
6. Check Coil Piping for Leaks
Pressurize the coil to 100 psig with dry nitrogen or
other suitable gas. The coil should be left pressurized
for a minimum of 10 minutes. If the coil holds the
pressure, the hook-up can be considered leak free.
If the pressure drops by 5 psig or less, re-pressurize
the coil and wait another 10 minutes. If the pressure
drops again, there is likely one or more small leaks
which should be located and repaired. Pressure losses
greater than 5 psig indicate a large leak that should be
isolated and repaired.
Distributor
Access Panel
Installation of Direct Expansion (DX)
Coil Piping (optional)
IMPORTANT
Guidelines for the installation of direct expansion
cooling coils have been provided to ensure proper
performance and longevity of the coils. These are
general guidelines that may have to be tailored
to meet the specific requirements of any one job.
As always, a qualified party or individual should
perform the installation and maintenance of any coil.
Appropriate protective equipment is recommended
during the installation and maintenance of the coil.
IMPORTANT
All field-brazing and welding should be performed
using high quality materials and an inert gas purge
(such as nitrogen) to reduce oxidation of the internal
surface of the coil.
IMPORTANT
All field-piping must be self-supporting and flexible
enough to allow for the thermal expansion of the coil.
1. Locate the Distributor(s) by Removing
the Distributor Access Panel
2. Verify Nozzle Placement
Inspect the refrigerant distributor and verify that the
nozzle is in place. The nozzle is generally held in place
by a retaining ring or is an integral part of
the distributor itself.
3. Install Suction Line
Install suction line(s) from the compressor to the
suction connection(s) which are stubbed through the
side of the cabinet.
Retainer
Ring
Nozzle Distributor
Nozzle Placement
NOTE
If an optional hot gas bypass kit was provided by
others, refer to the manufacturer’s instructions.
Thermal
(by others)
(by others)
Thermal
(by others)
Installation with Hot Gas Bypass
Thermal
(by others)
(by others)
Thermal
(by others)
General Installation
Distributor
Location
Model DG / DGX Pilot Ignition Make-Up Air 12
®