5-1
TROUBLESHOOTING
VFC 15-150 - VFC 45-225 MODULATING GAS BOILERS
5.0 TROUBLESHOOTING
The troubleshooting section is divided into 3 sections:
5.1 Preliminary Checks
5.2 Electronic Components
5.3 Troubleshooting Guide
Often,aproblemcanbeidentiedandsolvedthroughsimplechecksofthe
basics:conrmingtheelectricalpowersupply,gasowandresettingthe
thermostat control. To extend the cover of such preliminary checks, the boiler’s
control module offers a clear visual display of the status of the various control
circuit components.
Should a problem remain unsolved after applying the preliminary checks,
proceed to the detailed system review, using the Troubleshooting Guide. The
Guide covers potential error conditions as grouped into the following categories:
5.3.1 Using Control Module Errors Displayed
5.3.2 Ignition Problems
5.3.3 Cycling Problems
5.3.4 Temperature Problems
5.3.5 Miscellaneous
Below each section is a list of Symptoms, Diagnoses, and Remedies.
Also provided with this manual are a number of diagrams (see Section 6.0) for
use with troubleshooting including:
• Electrical Wiring Diagrams
• Sequence of Operations Flowchart
• Boiler Component Layout Diagrams
PRELIMINARY CHECKS
TherststepintroubleshootingthissystemshouldbeareviewoftheController’s
LCD screen. There are a number of diagnostic features incorporated in the
software that evaluate system integrity, display error conditions and provide initial
suggested remedial actions (see Section 2.5.6 Error Mode.)
In addition to checking the display, the following list is a guideline for
troubleshooting:
1. Conrmpowertotheboiler:checkthatcontrolmoduledisplayison(e.g.
display is lit).
2. Check that boiler is not in a safety lockout.
3. Ensure wiring is clean and secure.
4. Check that gas is reaching the unit.
5. Conrmwatersystemisproperlychargedto12psigandpumpis
serviceable.
5.1