Supply Air Temperature Rise Test; Limit Control Check; Restart After Burner Failure; Maintenance - Bryant OVM098 Installation Instructions Manual

CAUTION
Low flue gas temperature increases the risk of condensation.
Adjust the total temperature at or higher then 204°C (400°F) in order
for the heat exchanger warranty to remain in force.

3.3.7 Supply Air Temperature Rise Test

1. Operate the burner for at least 10 minutes;
2. Measure the air temperature in the return air plenum;
3. Measure the air temperature in the largest trunk coming off the
supply air plenum, just outside the range of radiant heat from
the heat exchanger. 0.3 m (12") from the plenum of the main
take-off is usually sufficient;
4. The temperature rise is calculated by subtracting the return air
temperature from the supply air temperature;
5. If the temperature rise is lower or exceeds the temperature
specified in Table 6, change to the next lower or higher blower
speed tap, until the temperature rise falls to the target. If the
excessive temperature rise cannot be increased or reduced by
changing fan speed, investigate for ductwork obstructions, dirty
or improper air filter, improper firing caused by improper pump
pressure or nozzle sizing.

3.3.8 Limit control check

After operating the furnace for at least 15 minutes, restrict the return
air supply by blocking the filters or the return air register and allow the
furnace to shut off on High Limit. The burner will shut off but the blower
will continue to run.
Remove the obstruction and the burner should restart after a few
minutes. The time required for the restart also depends on the
adjustment of the blower "OFF" delay.

3.3.9 Restart after Burner Failure

1. Set the thermostat lower than room temperature;
2. Press the reset button on the burner primary control (relay);
3. Set the thermostat higher than room temperature;
4. If the burner motor does not start or ignition fails, turn off
the disconnect switch and CALL A QUALIFIED SERVICE
TECHNICIAN.
CAUTION
Do not attempt to start the burner when excess oil has
accumulated, when the furnace is full of vapour or when the
combustion chamber is hot.

4 MAINTENANCE

Preventive maintenance is the best way to avoid unnecessary expense
and inconvenience. Have your heating system and burner inspected
by a qualified service technician at regular intervals and after extended
periods of shutdown.
To maintain the reliability and optimal performance of the furnace, have
a complete combustion check done after the annual maintenance call.
Do not attempt to repair the furnace or its controls. Call a qualified
service technician.
ALWAYS KEEP THE OIL SUPPLY VALVE SHUT OFF IF THE BURNER
IS SHUT DOWN FOR AN EXTENDED PERIOD OF TIME.
Before calling for repair service check the following points:
1. Check the oil tank gauge and make sure that the valve is open;
2. Check fuses and the circuit breaker;
3. Check if the main disconnect switch is ON ;
4. Set the thermostat above room temperature;
5. If ignition does not occur, turn off the disconnect switch and call
a qualified service technician.
When ordering replacement parts, please specify the complete
furnace model number and serial number.
4.1 CLEANING THE HEAT
EXCHANGER
It is not generally necessary to clean the heat exchanger or flue pipe
every year, but it is advisable to have the oil burner service technician
check the unit before each heating season to determine whether the
cleaning or replacement of parts is necessary.
If a cleaning is necessary, the following steps should be performed:
1. Turn OFF all utilities upstream from the furnace;
2. Disconnect the flue pipe;
3. Remove the flue collar panel located at the front of the furnace;
4. Remove the heat exchanger baffles;
5. Disconnect the oil line and remove the oil burner;
6. Clean the secondary tubes and the primary cylinder with a stiff
brush and a vacuum cleaner;
7. Before re-assembling the unit, the heat exchanger and
combustion chamber should be inspected to determine if
replacement is required;
8. After the cleaning, replace the heat exchanger baffles, flue collar
plate and oil burner;
9. Readjust the burner for proper operation.
4.2 CLEANING THE BLOCKED
VENT SHUT-OFF DEVICE
(BVSO)
For continuous safe operation, the Blocked Vent Shut-off device
(BVSO) must be inspected and maintained annually by a qualified
service technician.
1. Disconnect power to the appliance;
2. Remove the two screws holding on the BVSO assembly cover;
3. Remove the cover;
4. Remove the two screws holding the control box to the heat
transfer tube assembly. Sliding the control box in the appropriate
direction will unlock it from the heat transfer tube assembly;
5. Carefully remove any build-up from the thermal switch surface;
Do not dent or scratch the surface of the thermal switch. If
the thermal switch is damaged it MUST be replaced.
6. Clean and remove any build-up or obstruction inside the heat
transfer tube;
7. Re-mount, lock and fasten the control box with the 2 screws
removed in step 4;
8. Re-attach the assembly cover with the screws removed in step
2;
9. Re-establish power to the unit.
10
CAUTION