Installation Manual Switching Relay 303P The Switching Relay 303P connects up to three thermostats and operates circulators to provide heating to a zoned hydronic heating system.
Table of Contents Important Safety Information.......................................... 2 Installation....................................................................... 3 Packaging Contents.................................................... 3 Tools Required............................................................ 3 Materials Required...................................................... 3 Location...................................................................... 3 Installing the Enclosure.....
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.
Application 303P-1 The Switching Relay 303P operates the circulators for three heating zones when the corresponding thermostat calls for heat. The boiler is fired whenever a zone calls for heat.
Application 303P-2 The Switching Relay 303P operates three heating zone circulators when the corresponding thermostat calls for heat. Zone 1 heats a domestic hot water tank. When priority is selected, zones 2 through 3 shut off when zone 1 is heating. The boiler is fired when there is a call for heat.
Application 303P-3 Two Switching Relay’s operate seven heating zone circulators. The two controls are connected together using an expansion bus wire. The master 303P fires the boiler when any zone calls for heat. If priority is selected, zones 2 through 7 shut off when zone 1 is calling for heat.
User Interface - Indicator LED Power • On when 115 V (ac) is applied. • Off when power disconnected or transformer fuse is blown. Priority • On when zone 1 has priority over zones 2 and 3. • Flashing while in priority override. RoomResponseTM • On when modulating condensing boiler is operating below maximum setting. Zone 1 • On when thermostat 1 calls for heat. Zones 2 and 3 • On when the corresponding thermostat calls for heat. • Off during priority operation.
RoomResponseTM Signal The RoomResponseTM signal adjusts the temperature of a modulating condensing boiler that accepts a 0-10 V(dc) or 4-20 mA input. It works by continually adjusting boiler water temperatures to the lowest possible value to meet comfort without wasting energy. This is done by monitoring each thermostat's on and off time pattern and determines the ideal water temperature for each zone.
Aerco AM Series – Camus Modulating MicoFlame 22 23 + – 303P – + Aerco AM + 303P 5 6 – + Camus Micoflame • No changes to the boiler are required. • Change control to mode 6 in the control parameters. Bosch Greenstar Heat Transfer Products Elite – 9 10 + – 303P – + 16 17 + + 303P Bosch ICM – HTP Elite • Install the Bosch ICM as per the directions. • Set ICM jumper to the left position to enable system supply water temperature (VT) mode.
Laars Mascot FT – Peerless Pinnacle PF-200, 210, 300, 399 16 17 + + 303P – – Laars Mascot FT 15 16 + – 303P • No changes to the boiler are required.
Raypak XFyre and XPakFT – + X X 303P Viessmann Vitodens 200-W, B2HP and Vitocrossal 300 CU3A + – T 8 9 9 10 – T J2 J1 Raypak XFyre or XPakFT + 1 2 + – Viessmann Extension Module EA1 Plug 0-10V 303P • Set boiler PIM DIP switch 2 to Down. • Set boiler PIM DIP switch 5 to Up. • Connect to the Viessmann Extension Module EA1 Plug 0-10V.
Warranty Limited Warranty The liability of tekmar under this warranty is limited. The Purchaser, by taking receipt of any tekmar product (“Product”), acknowledges the terms of the Limited Warranty in effect at the time of such Product sale and acknowledges that it has read and understands same. tekmar Limited Warranty are the Purchaser’s sole responsibility and obligation.
