Onix Tubing Installation Manual

This double serpentine layout places
the cooler return end of the circuit
next to the warmer supply end. This
layout helps bring the finished floor
surface to an even temperature in the
shortest time possible.
Unless the zone has only one loop or
has a very short exterior perimeter, do
not heat more than half of the perime-
ter with one circuit.
Step 6:
Securing the Onix
Slab applications usually require some
form of fastener, depending on the
construction details. Most slab applica-
tions use rewire or rebar to add
strength or crack resistance to the slab.
In this application, the Onix attaches
directly to the rewire/rebar by the use
of cable ties or ClipTie clips. If the
slab is poured without the
rewire/rebar, other fasteners can be
used that will secure the Onix directly
to the foam insulation beneath the
slab.
After no more than three circuits have
been roughly laid out, tie down
enough of the bends in the circuits to
temporarily hold the Onix in place.
Lay out all of the remaining circuits in
the zone before tying down more than
the bends. This helps eliminate time
and wasted fasteners in the event cir-
cuits need to be moved or adjusted.
Repeat this process until all of the cir-
cuits with the zone are in position.
Leave 2’—5’ slack on each circuit in
case the manifold position needs to be
adjusted from its temporary location.
After all circuits are in place and any
adjustments have been made, fasten
the Onix to the wire mesh or insula-
tion board every one to two feet. This
will keep the Onix from shifting or
floating during the concrete pour. If
cable ties are used, do not pull the ties
so tight that the Onix is flattened or
pinched shut. Also, make sure all
tails of the cable ties are either cut
off or turned downward to prevent any
unwanted surface protrusions.
Step 7:
Repeat With The Next
Circuit
Repeat steps 4 through 6, keeping the
next circuit spaced according to the
design. Make sure to use as much of
each circuit as possible. If the last cir-
cuit is too long, which sometimes hap-
pens, try not to cut it to make it short-
er. Shorter circuits have a lower pres-
sure drop and will tend to cause an
imbalance in the fluid flow. Some tub-
ing may be removed from this last cir-
cuit as long as the remaining length is
within 10% of the existing circuits.
For example, if 200 ft. lengths were
installed, the last circuit can be cut to a
length of 180 ft. and still maintain a
balanced system. If more than 10% is
Watts Radiant: Onix Installation Manual page 41
in excess, run the remaining tubing
along an exposed wall or in other
areas of the zone.
Step 8:
Visual Inspection
After all circuits are installed, take a
few minutes to walk each circuit and
visually inspect the tubing for possible
damage caused during installation. If a
damaged area is found, repair it using
an approved Watts Radiant Repair Kit.
More information on repair kits can be
found in the Appendix.
Step 9:
Final Assembly and
Pressure Test
With the zone fully installed and
inspected, finish the connections to the
manifold. Begin by identifying corre-
sponding ends to the same circuit. If
the tubing has not been marked, select
two circuit ends and blow through one,
with a thumb placed over the other
end. Air should be felt on the other
side, confirming a single circuit has
been selected.
Take one Onix Clamp and slide it over
one end of tubing. Slide the clamp
down about 2" from the end and push
Manifold
Onix Barb
Onix Clamp
Onix
Manifold
Pressure Test Kit
Rewire/Rebar
Railway
Cable Tie
ScrewClip
ClipTie
FoamBoard Staple
Insulation
Subgrade/Earth
Slab
Various tube fasteners for slab applications.
Concrete Slab