Howe 1000-RLE, Installation & Service Manual

Page: 7 / 53

Engineer
ing
Guidelines
7
Piping Table
Model Liquid Line* Suction Line* Suction Riser*
1000 ‐ RLE 3/8” ODS 7/8” ODS 3/4” ODS
2000 ‐ RLE 1/2" ODS 1 ‐ 1/8” ODS 7/8” ODS
3000 ‐ RLE 1/2" ODS 1 ‐ 3/8” ODS 1 ‐ 1/8” ODS
*For runs up to 150 feet. If longer, use next larger line size.
Refrigerant Pipework
Howe recommends the field refrigerant piping
be installed according to the Suggested
Refrigerant Piping Diagram shown on previous
page. These pipe sizes are for HFC refrigerants
and are not applicable to R ‐ 744 installations or
secondary refrigerant applications.
Howe recommends the use of hard drawn ACR
type L tubing with refrigeration grade wrought
copper long radius elbows and fittings only. No
soft drawn tubing should be used in the
refrigerant pipe installation.
No field installed P ‐ type oil trap is required at
the base of the suction riser since all Ice Flakers
are internally piped with a suction trap at the
outlet of the evaporator within the enclosure.
Evaporator Pressure Regulator (EPR) valves
must be field installed with the arrow correctly
pointing in the direction of flow.
Installation specifications should require all
refrigerant piping should be joined with a
suitable silver brazing alloy while purging
nitrogen through the piping to prevent copper
oxidation scale from forming inside the tubing.
For close coupling Ice Flaker to Condensing
Unit, use a minimum of ten feet total straight
length of pipe. Minimize bends and fittings.
Suction Line to include EPR and Heat Exchanger.
Refrigerant Pipework Insulation
Requirements
Field refrigerant pipework should be insulated
with closed cell flexible elastomeric foam
thermal insulation intended for cold
applications.
Liquid lines should be covered with 1/2” thick
and suction lines with 3/4” thick material.
The insulation material should be moisture
vapor resistant when correctly installed
according to the manufacturer’s instructions.
The field installed Evaporator Pressure
Regulator (EPR) valve and Suction Line Heat
Exchanger must likewise be insulated. If these
system components are left un ‐ insulated they
become “thermal bridges” and unwanted
condensation and ice will form and drip.
All butt joints and seams must be properly field
fabricated according to the insulation
manufacturer’s fusing adhesive instructions.
Self ‐ adhering closed cell foam insulation is also
available in rolls and can be used to supplement
the conventional tubular materials on irregular
shapes, EPR valves, and caps.