Watts Tekmar Switching Relay 302P-3, Switching Relay 303P Series, Tekmar Switching Relay 302P Series, Switching Relay 303P-1, Switching Relay 303P-2 Installation Manual

Installation Manual

Switching Relay 302P

Two Zones with Priority

H3024A

Power

Priority

Zone 1Zone 2

RoomResponse

TM

Switching Relay 302P

The Switching Relay 302P connects up to two thermostats and operates circulators to provide heating to a zoned
hydronic heating system.

Features

• RoomResponseTM signal

• Compatible with all low voltage thermostats

• Unlimited zone expansion

• Zone priority

• Priority override

• Pump exercising

• Post purge

• Away signal shared between tekmar thermostats

• LED for each zone, priority, end switch and
RoomResponse

TM

• Four ground screws

• Top, bottom and back conduit knockouts

• Fuses protect transformers and pumps

• Two spare fuses included

• CSA approved

Table of Contents

Important Safety Information ......................................... 2

Installation ...................................................................... 3

Packaging Contents ................................................... 3

Tools Required ...........................................................3

Materials Required ..................................................... 3

Location ..................................................................... 3

Installing the Enclosure .............................................. 3

Application 302P-1 .................................................... 4

Application 302P-2 .................................................... 5

Application 302P-3 .................................................... 6

User Interface ................................................................. 7

Indicator LED ............................................................. 7

Sequence of Operation .................................................. 7

Technical Data .............................................................. 11

Limited Warranty and Product Return Procedure ........ 12

Important Safety Information

It is your responsibility to ensure that this control is safely installed according to all applicable codes and standards.
tekmar is not responsible for damages resulting from improper installation and/or maintenance.

This is a safety-alert symbol. The safety alert symbol is shown alone or used with a signal word (DANGER,
WARNING, or CAUTION), a pictorial and/or a safety message to identify hazards. When you see this
symbol alone or with a signal word on your equipment or in this manual, be alert to the potential for
death or serious personal injury.

This pictorial alerts you to electricity, electrocution, and shock hazards.

This symbol identifies hazards which, if not avoided, could result in death or serious injury.

This symbol identifies hazards which, if not avoided, could result in minor or moderate injury.

This symbol identifies practices, actions, or failure to act which could result in property damage or
damage to the equipment.

Read manual and all product labels BEFORE using the equipment. Do not use unless you
know the safe and proper operation of this equipment. Keep this manual available for easy
access by all users. Replacement manuals are available at tekmarControls.com

• It is the installer’s responsibility to ensure that this control is safely installed according to all applicable codes
and standards.

• Improper installation and operation of this control could result in damage to the equipment and possibly even
personal injury or death.

• This control is not intended for use as a primary limit control. Other controls that are intended and certified as
safety limits must be placed into the control circuit.

The control includes fuses and transformer that are serviceable. Do not attempt to service any other parts on the
control. Attempting to service the control voids the warranty.

• Strip all wiring to a length of 3/8 in. or 10 mm for all terminals.

• A circuit breaker or power disconnect that provides power to the control should be located nearby and clearly labeled.

• Refer to the current and voltage ratings at the back of this manual before connecting devices to this control.

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Radio Frequency Interference

The installer must ensure that this control and its wiring
are isolated and/or shielded from strong sources of elec­tromagnetic noise. Conversely, this Class B digital appa­ratus complies with Part 15 of the FCC Rules and meets
all requirements of the Canadian Interference-Causing
Equipment Regulations. However, if this control does
cause harmful interference to radio or television reception,
which is determined by turning the control off and on,

Installation

Packaging Contents

• 1 Switching Relay 302P

• 2 Spare fuses (located in cover)

Tools Required

• tekmar or jeweler screwdriver

• Phillips head screwdriver

Materials Required

• 18 AWG LVT solid wire (low-voltage connections)

• 14 AWG solid wire (line-voltage connections)

the user is encouraged to try to correct the interference
by re-orientating or relocating the receiving antenna,
relocating the receiver with respect to this control, and/
or connecting the control to a different circuit from that
to which the receiver is connected.

Cet appareil numérique de la classe B respecte toutes
les exigences du Règlement sur le matériel brouilleur du
Canada.

• Installation Manual 302P_D

• Needle-nose pliers

• Wire stripper

• Four 1/8” - 1” wood screws

Location

• Keep the control dry. Avoid potential leakage onto the control.

• Maintain relative humidity less than 90% in a non-condensing environment.

• Avoid exposure to extreme temperatures beyond 32-122°F (0-50°C).

• Install away from equipment, appliances, or other sources of electrical interference.

• Install to allow easy access for wiring, viewing, and adjusting the display screen.

• Install approximately 5 feet (1.5 m) off the finished floor.

• Locate the control near pumps if possible.

• Provide a solid backing which the enclosure can be mounted to. Example: plywood or wall studs.

• Use the conduit knockouts provided on the upper, lower, and back of the enclosure for wiring.

Installing the Enclosure

To prevent the risk of personal injury and/or
death, make sure power is not applied to the
control until it is fully installed and ready for
final testing. All work must be done with power
to the circuit being worked on turned off.

Please be aware local codes may require
this control to be installed or connected by
an electrician.

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Application 302P-1

The Switching Relay 302P operates the circulators for two heating zones when the corresponding thermostat calls for
heat. The boiler is fired whenever a zone calls for heat.

Mechanical

Legend

B1 = Boiler
P1, P2 = Zone 1 and 2 Pumps
T1 = WiFi Thermostat 561, 562 or 563
T2 = Generic Digital Power-Stealing Thermostat

302P

Electrical

B1

B1

T1

70

Away C R Rh W

-

+

XX

MOD

POWER ROOM

A

DHW CRW

tN4

BOILER T-STAT 1T-STAT 2T-STAT 3

RESPONSE

FUSE 1

120 VAC
POWER

L

A

tN4

T1 T2 T3 T4 T5 T6

FUSE 7

FUSE 8

FUSE 2

PRIORITY

PUMP 1

NLNLNL NLNLNLN

T2

R W

A

CRW

tN4

FUSE 3FUSE 4FUSE 5

PUMP 2PUMP 3PUMP 4PUMP 5PUMP 6

CRW

A

tN4

T-STAT 4

CRW

A

tN4

T-STAT 5

CRW

P1 P2

A

tN4

A

CRW

tN4

T-STAT 6 EXPANSION

MASTER MEMBER

T-STAT 1 PRIORITY : 0N

EXERCISING : ON

POST PURGE : ON

MOD BOILER : 0-10V

RESERVED

50 100

MOD MAX %

FUSE 6

BCDE

70 80

9060

DIP Switches

Master
T-stat 1 Priority Off
Exercising On
Post Purge On
Mod Boiler - not applicable

OFF
OFF
OFF
4-20 mA

The 302P includes
internal circuitry
to support power
stealing thermostats.
External resistors are
not required.

L N

P1 P2

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