Let's examine a practical scenario that
gives you more insight into terminal units:
You have double-checked your terminal unit order to make sure every detail has been provided. The material, voltage, accessories and controls are selected. Knowing that everything has been evaluated and entered correctly, the order is submitted. Now, on to the next one!
Later, you receive a call about the
order you so confidently completed. On the other end of the phone is the
installing contractor, and he is flipping-out! This is actually more literal
than figurative.
The units are said to not fit into the
allocated critical spaces, due to an improper handing specification. Controls
were ordered for the right-hand side, but they have arrived on the left.
Maybe the piping for the hot-water
reheat coils should be on the left, but the connections were shipped on the
right. All of a sudden, a seemingly minor detail has become a massive
emergency. What can be done?
Determining the Solution:
Do you have what is needed to
extinguish the fire? Although not every unit can be rotated, it may be possible
in your case.
There are important aspects to
understand when deciding if a unit is able to be flipped from its intended
working position. We will examine this, unit by unit.
Cooling Only Units:
Single-duct terminals (ESVs) can be
turned 90°, 180° and every other degree in between. They do not have any
position-sensitive parts or equipment that prohibits their mounting
orientation. Further consideration, however, is needed when you add controls to
the unit. Pneumatic controls are position sensitive, meaning that PESVs must be
adjusted before they are rotated.
Fan-powered boxes may only be rotated
180°. You must take into consideration that all of our units do not have top
and bottom accessibility.
TFS & TFS-F units have top and
bottom access panels, which allows for access to the motor – after rotation --
from the bottom of the unit. All other Titus fan-powered boxes are unable to be
accessed from the top, unless the unit is flipped.
Parallel units cannot be flipped, due
to the gravity-operated backdraft damper that is installed on the outlet of the
fan deck. This backdraft damper remains open if the unit is rotated, which
hinders the unit’s performance. The position sensitivity of pneumatic controls
is applicable to fan-powered units as well.
Units with Electric Reheat:
When it comes to units that utilize
electric reheat -- single duct or fan-powered -- careful consideration must be
taken. The airflow switch used in Titus’ electric heaters is position
sensitive. You can rotate a unit with electric reheat, but you are limited to a
full 180°.
Any other mounting orientation has the
potential to impede performance. The airflow switch is an important safety
component for the heater. It is better to err on the side of caution and not
get too creative.
If ever there is uncertainty, please
contact Titus Terminal Unit Applications for more clarification.
Units with Hot-Water Reheat:
With use of hot-water reheat coils
trending, knowing whether you can flip one has become a very vital piece of
information. The performance of how-water reheat coils is integral to the
overall functionality of the unit, so there is concern that flipping a coil
will adversely alter performance.
Counterflow is the cause for this
concern. Our 1-row and 2-row water coils are of a cross-flow construction, and
we do not recommend rotating these coils. Titus does make left-hand and
right-hand coils available for 3-row and 4-row. The thing to remember when
flipping a water coil is the water always enters through the bottom and exits
through the top.
A terminal unit that arrives on site
with the wrong handing is not the end of the world. If you find yourself in
this situation, remember it may be alright to flip-out!
Please direct
questions toward Titus Communications
(communications@titus-hvac.com) and/or Titus' Terminal Unit, UnderFloor
Air Distribution Product Manager Derrick Smith (dsmith@titus-hvac.com).
