![7.Attach unit risers:](/images/new-backgrounds/33740/3374083x1.webp)
h.After all drywalling and painting is complete, install thermostats, supply air grilles and return air panels.
7.Attach unit risers:
CAUTION
Toxic residues and loose particles resulting from manufac- turing and field piping techniques such as joint compounds, soldering flux, and metal shavings may be present in the unit and the piping system. Special consideration must be given to system cleanliness when connecting to solar, domestic or portable water systems. Failure to heed this warning could result in equipment damage.
NOTE: The supply and return connections are marked on the coil
a.Each riser has a
If job requires that unit risers be supplemented with
b.Level unit to ensure proper coil operation and condensate drainage. Proper riser installation and vertical positioning in the unit provides for a unit piping
c.Anchor unit to building. Use bolts or lag screws through holes provided in unit frame.
d.After all units in a stack are anchored, make unit-
e.Before making the riser joints, the riser insulation must be pulled back away from the joint and pro- tected from heat during the soldering process. Sol- der riser joints with
IMPORTANT: Chilled water and hot water risers should never be piped to drain down into the condensate riser. Extensive water damage can occur due to drain over- flow. Drain chilled and hot water risers to a remote loca- tion away from the unit such as sink, room and floor drains.
8.Anchor risers as required:
a.Do not fasten risers rigidly within each unit. Risers must be free to move within pipe chase in response to normal vertical expansion and contraction.
b.Built in risers must be anchored at some point to building structure. Unit design accommodates up to
9.Test the system for leaks after the connections are com- pleted. When testing with air or some other gas, it might be necessary to tighten stem packing nuts on some valves to maintain air pressure in the riser. Pressure testing risers with water should be done with the unit service valves closed to prevent flushing debris into the unit valve pack- ages. This will also allow risers to be drained down after testing in the winter to avoid
10.After system integrity has been established, pull the riser insulation back into place over the joint and glue or seal to prevent sweating and heat loss or gain. Internal chilled water piping and valves are located over the drain pan and need not be insulated.
11.If required, fireproof were necessary. Any fireproofing re- quirements where risers or piping penetrate floors or walls are the responsibility of the installer. This work should be done only after all pressure testing is complet- ed. The fireproofing method used must accommodate pipe expansion and contraction and the piping must be protected from abrasion and chemical attack. The pipe in- sulation also must be maintained to prevent sweating and must be protected from wear or erosion at the joint be- tween the insulation and the fireproofing material.
Step 2 — Make Piping Connections — Access to piping is available through the access panels at the side of the units or front of the unit. Qualified personnel in accordance with local and national codes must perform all piping connec- tions. Refer to Tables
NOTE: It is important to have a common understanding of which side of the unit is the right hand side and which is the left hand side.
When facing the supply air outlet from the front of the unit (air blowing in your face), your right hand will be on the right side of the unit and your left hand will be on the left side of the unit. See Fig. 40. Refer to Fig. 41 and 42 for typical piping connections.
The supply and return piping connections of the factory- provided valve package are either swaged for field brazing (standard) or union fitted (optional) for field connection to the coil.
42