the surrounding air pressure. Inspection of the boiler and vent system is necessary to insure that flue gas leakage to the surrounding area does not occur.
Inspect the external surfaces of the vent system every 3 months for corrosion and leakage. Inspect the vent terminations for corrosion and foreign matter which may be blocking the exhausting flue products. Call a qualified service agent to replace or repair any corroded or leaking parts.
A qualified service agent must inspect the internal surfaces of the vent system and the boiler at least once a year.
BURNER SYSTEM
To maintain safe operation and the greatest efficiency for the boiler, observe the burner flame through the observation port on the jacket panel, once a month for proper flame characteristics.
•The burners should display the following characteristics:
•Provide complete combustion of gas.
•Cause rapid ignition and carry over across all burners and across the entire burner.
•Give quiet operation during ignition, burning and extinction.
•Cause no excessive lifting of flames from the burner ports.
If the preceding characteristics are not evident, check for accumulation of lint or other foreign material that restricts the inlet air or burner ports. Ensure there is the proper amount of air to the burner. Flame lifting from the burner is caused by too much air to the burner.
The burners must be inspected by a qualified service technician at least once a year.
DO NOT STORE COMBUSTIBLE MATERIALS, GASOLINE, OR OTHER FLAMMABLE VAPORS, LIQUIDS IN THE AREA OF THE APPLIANCE. NONCOMPLIANCE MAY RESULT IN FIRE OR EXPLOSION. DO NOT OBSTRUCT THE FLOW OF COMBUSTION OR VENTILATION AIR TO THE APPLIANCE.
CHEMICAL VAPOR CORROSION
Boiler corrosion and component failure can be caused by airborne chemical vapors. Spray can propellants, cleaning solvents, refrigerants, calcium or sodium chloride (water softener salts), waxes, and process chemicals are typical compounds that are potentially corrosive. These materials are corrosive at very low concentration levels with little or no odor to reveal their presence. Products of this sort should not be stored near the boiler. Air which is brought in contact with the boiler should not contain any of these chemicals. The boiler should be provided with air from outdoors when installed in environments having corrosive atmospheres.
CIRCULATION PUMP
Refer to the pump manufacturer's schedule of maintenance for frequency and method of lubricating the pump and motor. Inspect the pump once a month for leaky mechanical seals and/or O-rings and loose or damaged components. Contact a qualified service agent to replace or repair parts as required.
ELECTRONIC HOT SURFACE
IGNITION CONTROL BOARD
The EMC5000 control system is a fully integrated, state of the art electronic control system. It consists of sensors, output devices, a power switch, a 24vac transformer, wiring, and the following printed circuit boards:
Central Control Board (CCB). | See Figure 1A. |
Flame Control Board (FCB). | See Figure 1B. |
User Interface Board (UIB). | This part of the User Interface |
| Module (UIM). See Figure 3. |
Power Distribution Board (PDB). See Figure 1C. |
Touch Sensor Board (TSB). | This is part of the User |
| Interface Module (UIM). See |
| Figure 3. |
The CCB contains circuitry for both master control and flame control for the first stage. The FCB contains circuitry for flame control on up to one additional stage. Dip switches on the CCB and FCB are used to configure the system. The UIB and TSB are included in the User Interface Module (UIM) along with a 4 line by 20-character LCD display. The PDB provides connection points for input power, the water pump, and the transformer. It also distributes power to the system and contains the system fuses.
Dual stage control is accomplished by means of an internal communication network and the FCB's. One FCB is required for each stage beyond initial first stage. The CCB also contains an external communications system to allow for connection to a PC, a modem, or an EMS system. Through this connection multiple boilers can also be linked together.
CAUTION
The internal communications cables should never be connected to the external communications connectors and vice-versa.
There are several microcontrollers used on the board. Three on the CCB, two on the FCB, and one on the UIB. These micros control the temperature and ignition control functions for the boiler. Inherent in the design are the normal operating sequences and safety features associated with a gas ignition control system. The system continuously performs various diagnostic tests to verify proper appliance and control operation. Should an unsafe condition occur, the control will shut down the burner and display a red fault light as well as indicate the cause of the fault on the display. The operating programs for the system are stored in permanent memory inside the micros. User-selectable operating parameters and a history of detected faults are stored in re-writable memory in the micros. A loss of power does not affect either of the memories.
Inputs To CCB and FCB:
•Temperature Sensors:
•Temperature probes (CCB - outlet and either inlet or tank is required): The CCB accepts analog temperature inputs from up to three sensors (inlet, outlet and tank).
•ECO input (CCB - required):
The ECO (Energy Cut-Off) is a Hi-Limit switch, which is located inside the output probe. It is a normally closed switch that opens if the probe is exposed to a temperature higher than the trip point.
•Thermostat input (CCB - optional):
This input is set up to work with an externally connected thermostat that provides a contact closure. If this input is
