UNICONTROL Electronic Cleveland Controls RSS-495-011 User manual

Cleveland Controls
Division of UniControl Inc.
APPLICATION
The Series RSS-495-011 Sensing Switch
Kit provides an economical and convenient
solution for many residential and light com-
mercial HVAC applications. The kit contains
a compact Series RSS-495 switch with an
adjustable set point range of 0.20" w.c. to
1.0" w.c. The switch has been factory set
to actuate on a pressure rise of 0.20" w.c.
The switch has a bleed hole (.016") in the
mounting pan. The individually boxed kit
includes a P/N 28419 hex wrench (1⁄16") for
eld calibration, a P/N 28429 tube-to-tube
reduction adapter, and two (2) P/N 27577-
037 slotted hex head mounting screws (#6
x ⅜").
GENERAL DESCRIPTION &
OPERATION
The RSS-495 switch has a thermoplastic
housing containing a diaphragm and snap-
acting switch. Duo-barbed sample line
connectors on each side of the diaphragm
accept ¼" ID or ⅜" ID slip-on exible tubing.
The .016" bleed hole in the mounting pan
(low pressure side) prevents the build up of
condensation in the switch and sample line.
The electrical connection consists of three
(3) male 90º quick-connect terminals. The
snap action switch can be actuated by a
positive or negative pressure, or by a pres-
sure differential.
MOUNTING (FIGURE 1)
Select a mounting location that is free from
vibration. Mount with the diaphragm in
any vertical plane in order to maintain the
specied operating set point. Do not mount
with the sample line connections directed
upward. Surface mount via the two 0.14"
slots in the integral foot bracket, using the
two (2) slotted hex head mounting screws
(#6 x ⅜") provided in the kit.
AIR SAMPLING CONNECTION
(FIGURE 2)
Refer to Figure 2 to identify the High inlet
(H) and the Low inlet (L). Connect the
sample lines as follows:
Positive Pressure Only: Connect the
sample line to H; Lremains open to the
atmosphere.
Negative Pressure Only: Connect the
sample line to L; Hremains open to the
atmosphere.
Two Negative Samples: Connect higher
negative sample to L; lower sample to H.
Two Positive Samples: Connect higher
positive sample to H; lower sample to L.
One Positive and One Negative: Connect
positive sample to H; connect negative
sample to L.
ELECTRICAL CONNECTIONS
(FIGURE 3)
Before pressure is applied to the diaphragm,
the switch contacts will be in the normally
closed (NC) position as shown in Figure 3.
Connect the application wiring to the corre-
sponding switch terminals, NC, NO, and C.
FIELD ADJUSTMENT
(FIGURE 4)
The adjustable set point range of the RSS-
495 is 0.20" w.c. to 1.0" w.c., ±0.05" w.c.
The switch leaves the factory calibrated
at 0.20" w.c. To adjust the set point, insert
the 1⁄16" hex wrench (provided with the kit)
into the adjusting screw located between
the mounting feet on the underside of
the switch. Holding the switch so that the
diaphragm is vertical, rotate the adjusting
screw clockwise to the desired set point. The
maximum number of turns is 4-½, covering
Model
RSS-495-011
AIR PRESSURE SENSING SWITCH KIT WITH ADJUSTABLE SET POINT
the set point range of 0.20" w.c. to 1.0" w.c.
Do not exceed the maximum number of
turns. Each full turn represents approxi-
mately 0.18" w.c. Determine the number of
turns required to approximately position the
adjusting screw as follows:
(REQUIRED SET POINT – INITIAL SET POINT @ 0.20)
0.18
= NUMBER OF TURNS CLOCKWISE
EXAMPLE:
REQUIRED SET POINT = 0.65" w.c.
INITIAL (FACTORY) SET POINT = 0.20" w.c.
(0.65 – 0.20) / 0.18 = 2.5 TURNS
Please note:
(1) Use a digital manometer and multi meter
(such as the Cleveland Controls Series
6650 Digital Manometer) to achieve pre-
cise set point calibration. Have the RSS-495
switch as close to actual operating tem-
perature as possible during the calibration.
The Cleveland Controls Series PVG-1
Pressure/Vacuum Generator provides a
handy air source for calibration.
(2) Warning: Never place an air
pressure sensing switch into operation
without conrming the set point rst. An
incorrect setting could result in a hazard-
ous condition.

SPECIFICATIONS
MODEL RSS-495-011
CONTRACTOR KIT
Mounting Position:
Mount with the diaphragm in any vertical plane.
Field Adjustable Set Point Range:
0.20 ±0.05" w.c. to 1.0 ± 0.05" w.c.
Factory Set Point for RSS 495-011:
Ships factory set at 0.20" w.c.±0.05" w.c.
Measured Media:
Air or combustion by-products that will not
degrade polyisoprene and thermoplastic
Maximum Pressure:
1 psi (0.06 bar)
Operating Temperature Range:
-40 ºF to 190 ºF (-40 ºC to 88 ºC)
Life:
100,000 cycles minimum at 1 psi
maximum pressure each cycle and
at maximum rated electrical load
Electrical Rating:
5 amp noninductive 120 to 277 VAC
1 amp pilot duty (120 Va) at 120 VAC
Contact Arrangement: SPDT
Electrical Connections:
(3) male 90° ¼" quick-connect spade terminals,
in compliance with NEMA standards.
Sample Line Connectors:
Barbed ttings accept ¼" ID or ⅜"
ID exible, slip-on tubing.
Approvals: UL, CUL, CSA, CE,
Australian Gas Association.
Shipping Weight: ¼ lb., approx.
Nominal Dimensions in Inches (Millimeters)
CARBON MONOXIDE (CO) GAS EXPOSURE
CAN CAUSE BRAIN DAMAGE OR DEATH
This pressure switch may control air ow into the combustion
chamber. Improper adjustment of the pressure switch in the
eld, or use of the switch for an application for which it was not
intended, may introduce carbon monoxide into the ventilation
system or combustion chamber. The U.S. Consumer Product
Safety Commission warns that carbon monoxide gas is an
“invisible killer.” Carbon monoxide (CO) is a colorless, odor-
less, deadly gas produced by burning fuel, including natural
gas and propane. Symptoms of carbon monoxide exposure
include dizziness, headache, nausea, weakness, sleepiness,
muscle twitching, vomiting and inability to think clearly. If you
experience these symptoms, turn the HVAC system off, exit
the building, and get into fresh air immediately. The pressure
switch must be tested thoroughly by an HVAC professional
before the HVAC system is restarted. Proper installation,
operation and maintenance of fuel-burning appliances and
HVAC systems is the most important factor in reducing carbon
monoxide poisoning. For safe operation, be sure all such de-
vices are installed by professionals and operated according to
manufacturer’s instructions and applicable local codes. Have
HVAC systems (including pressure switches) inspected and
serviced annually by a trained service technician. Examine
vents regularly for improper connections, visible cracks, rust
or stains, and blockage.
Install battery-operated carbon monoxide alarms certied to
the requirements of the most recent UL, lAS and CSA stan-
dard for carbon monoxide alarms. Test the alarms regularly
and replace the batteries annually.If you have any questions
regarding the installation, use or safety of this switch, please
call Cleveland Controls Customer Service at [phone].
Fig. 1: Mount with the diaphragm in any vertical
plane. Sample line connections must not
point upward.
Fig. 2 (left): Duo barbed sample line connectors
located on either side of the diaphragm
accept ¼" ID or ⅜" ID exible, slip-on
tubing.
Fig. 3 (right): Before pressure is applied to the
diaphragm, the switch contacts are in the
NC position, as shown here.
Fig. 4:Turns of the set point adjustment screw.
CONTENTS OF KIT CARTON
• (1) RSS-495 switch
• (1) P/N 27577-037 slotted hex
screw, #6 x ⅜"
• (1) P/N 28419 hexagon key, short
arm, 1⁄16"
• (1) P/N 28429 reduction connector,
tube to tube
• (2) P/N 27577-037 switch mounting
screws, slotted hex, #6-⅜"
• (1) Bulletin LT-RSS-495-011-xx
Fig. 1
Fig. 4
Fig. 2 Fig. 3