Brochure

T-3100, T-3200, and T-3300 Series Controllers Product/Technical Bulletin 7
I
nstallation Procedures
Tubing Installation
The T-3100, T-3200, and T-3300 Series Thermostats are
supplied with barbed fittings for the supply and the output
air connections. It is recommended that Type “FR”
polyethylene tubing be used on the barbed fittings.
Note: Cut tubing off square for a good fit on the barbed
fitting.
If “HP” or copper tubing is used, the barbed fitting must be
removed and replaced with a compression fitting and an in-
line restrictor when necessary.
Note: Figure 10 illustrates a copper tubing installation;
“HP” tubing installation is the same except the
brass ferrule is replaced with a thermoplastic
ferrule, which is supplied with the R-3710-1007
restrictor.
Standard Compression
Fitting (Field Furnished)
1/8 inch NPT, Internal Thread
Supply Air Connection
.007 inch In-Line
Restrictor with O-Ring
Brass Ferrule
(Field Furnished)
Compression
Nut
1/4 inch O.D.
Soft Copper Tubing
Air
Flow
Figure 10: Copper Tubing Installation
(Use R-3710-1007 In-Line Restrictor)
Sensing Elements
Both the bulb and the averaging sensing element must be
carefully located so the elements measure only the intended
air temperature. The majority of terminal air condition units
are very compact and little clearance exists between coils.
Also, the air flows are of widely varying temperature.
Before selecting an element location, study the unit interior
and make certain that the sensing element will not be
affected by undesirable temperatures or mechanical damage.
Avoid extremely sharp bends in the capillary which could
obstruct the liquid flow.
Route the capillary so it is not in contact with extremely high
or low temperature sources such as steam lines, water pipes,
or coils. Be sure to route the element and capillary so that
routine maintenance can be performed on the terminal unit
without disturbing the element.
Bulb Element
In most cases, a bulb element will be installed in the return
air chamber of the terminal air unit in the following manner:
1. Install the element behind the protective screen or grille
and in a location where normal maintenance may be
performed on the unit without interference.
2. Be sure the bulb will sense only the return air and will
not be influenced by other temperatures.
3. Secure the bulb using holder, T-275-100 (ordered
separately) which can be hung or fastened in place and
bent to the desired position.
Holder
8
203
Bulb
5/16
8
Diameter Hole
Figure 11: Bulb Element Holder Dimensions,
in./mm (T-275-100, ordered separately)