Figure 12: L7248 Circuit Board Layout -

Horizontal Mount

E.DISPLAY READOUT

In the RUN mode, the Aquastat will flash "bt"

(boiler temp) followed by the temperature (i.e., 220), followed by °F or °C.

To read boiler settings, press the I key to read the parameter of interest. For example, press I High Limit (HL) is displayed, followed by a three-digit number, i.e., 220, followed by °F or °C. See Display Readout, Figure 13.

Figure 13: Display Readout Definitions

After approximately 60 seconds without any key presses, the display will enter a dim display mode. To return to the bright display mode, simply press any key.

F.OPERATION

The L7248 model is restricted to three operational states - Normal, High Limit and Error. The controller moves back and forth from High Limit to Normal state as part of normal operation.

The controller will enter the Error state when there is an abnormal condition. The operating states are:

(1)Normal: Boiler temperature went below the High Limit setting (minus the Differential) and has not exceeded the High Limit setting; or the boiler temperature went above the Low Limit

setting and has not gone below the Low Limit setting (minus the Differential).

(2)High Limit: Boiler temperature went above the High Limit setting and has not dropped below the High Limit setting (minus the Differential).

table 4: LED error codes

Error

Cause / Action

Code

 

Err1

Sensor fault; check sensor.

Err2

ECOM fault; check EnviraCOM™ wiring.

Err3

Hardware fault; replace control.

Err4

B1 fault; check B1 wiring/voltage.

Err5

Low Line; check L1-L2, 110 Vac.

Err6

Fuse; check ECOM wires, replace fuse.

Err7

EEPROM, HL, Hdf; reset to default values.

Restore desired settings.

 

Err8

Repeated B1 fault (voltage present at B1 when

output is turned off); check B1 wiring/voltage.

 

(3)Error: The controller has detected an error condition (e.g., open sensor) and has shut down

table 5: l7248 controller operating sequence

Action

System Response

Thermostat

Circulator starts when water temperature

calls for heat.

is above Low Limit setting (if applicable).

 

Boiler temperature is checked. Burner

 

starts when water temperature is below

 

High Limit setting.

Boiler

Burner is turned off. Burner restarts when

exceeds the

the water temperature drops below the

High Limit.

High Limit setting minus the Differential.

Thermostat is

Circulator and burner turn off.

satisfied.

 

Error

If an error condition is detected, all outputs

condition 1-5.

except ZC are shut down. Burner is off.

 

Control continues to function and restarts

 

when error is corrected.

 

During the error check sequence, the

 

system checks for drift in the sensor and

 

corrosion in the connections.

Error

EnviraCOM communication is not

condition 6.

available.

Error

The control has reset the High Limit

condition 7.

setting to a default setting and will

 

continue to run at those settings.

 

Performance of the system will be

 

degraded.

Error

If the error condition is detected, all

condition 8.

outputs except ZC are shut down. Burner

 

is off. Control continues to function and

 

restarts when all three user keys have

 

been pressed longer than 60 seconds.

13

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Page 13
Image 13
Burnham L7248 manual Display Readout, Operation
Page 12 Page 14

L7248 specifications

The Burnham L7248 is a notable model in the realm of heating solutions, designed specifically for residential and commercial use. Renowned for its efficiency and reliability, the L7248 embodies innovative technology combined with user-friendly features, catering to diverse heating needs.

One of the key features of the Burnham L7248 is its advanced heating technology. It employs a gas-fired system that provides both hot water and space heating. This dual-function capability ensures that homes remain warm and comfortable during the colder months while also supplying hot water for daily use. The integrated control system allows users to manage the heating effectively, ensuring maximum comfort with minimal energy expenditure.

The L7248 is designed with durability in mind. Constructed from high-quality materials, the boiler is built to withstand the rigors of regular use while maintaining peak performance. Its advanced heat exchanger design enhances efficiency by ensuring optimal heat transfer, which translates to lower energy costs and a reduced environmental footprint. Furthermore, the unit operates quietly, providing a peaceful environment without intrusive noise.

In terms of safety, the Burnham L7248 incorporates several features that protect both the system and the home. It is equipped with advanced safety controls that monitor pressure and temperature, preventing potential hazards. Additionally, the unit’s design allows for easy servicing and maintenance, ensuring that it remains in good working condition for many years.

Energy efficiency is another hallmark of the Burnham L7248. With an impressive AFUE (Annual Fuel Utilization Efficiency) rating, the model significantly reduces fuel consumption, helping homeowners save on energy bills while promoting sustainability. The boiler is also compatible with various smart home technologies, allowing users to integrate it into their existing systems for enhanced control and efficiency.

Overall, the Burnham L7248 stands out for its combination of innovative technology, safety features, and energy efficiency. Whether for residential or commercial applications, it provides a solid, reliable heating solution that meets the demands of modern living. With its user-focused design and robust performance characteristics, the Burnham L7248 is an excellent investment for those seeking dependable and efficient heating.
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