On Rate for Fuel Oil Equipment

1. On Rate for Fuel Oil Equipment

2. Purpose • To insure that the equipment is delivering the correct heating value • Oil fired equipment must fire within 5% of the equipment nameplate to achieve this efficiency

3. To provide the oil heating value that the customer paid for we need: • Proper input of the fuel oil • Proper combustion air • Proper venting • Proper blower speed • Proper CFM • Proper ductwork

4. Confirm proper input of the fuel oil • Verify nozzle flow and spray angle for correct firing per the nameplate input • Verify oil pump pressure for the nozzle at the OEM values

5. Confirm with combustion analysis test • Proper combustion air • Proper venting • Proper blower speed, CFM and ductwork can be determined by air flow calculations if necessary

6. Confirm Temperature Rise • Procedure • Measure the temperature rise at steady state conditions • The unit must be running for several minutes and the conditioned space near the normal temperature • Record the temperature of the supply and return air • Subtract the return air temperature from the supply air temperature

7. Compare the rise to the equipment nameplate • The target is the middle of the range listed on the nameplate. Ex. 40 – 70* rise = 60* midrange

8. Caution! • Location where readings are taken is critical for temperature rise • For the supply air temperature the reading must be taken away from the heat exchanger • The probe should be inserted several feet downstream where there is a good mix of air and a good average reading can be taken.

9. Combustion Analysis • Perform a combustion analysis test • Make adjustments as needed • Repeat above if major change is made in the efficiency of the appliance

10. Results • Should the testing reveal that the system is not delivering the desired results further investigation into why must be conducted.