Powrmatic Air Heater NV50-F

Inspect fan blades for damage and excessive deposits

Is it necessary to remove the assembly for cleaning?

Slacken the cable gland on the heater casing

Disconnect fan leads from electrical terminals on the PCB

Withdraw cable through entry grommet

Remove fan and motor assembly by removing four hexagon headed bolts

Disconnect the electrode leads from the PCB terminal

Remove the screw securing the electrode assembly to the burner assembly side plate

Withdraw the electrode assembly

Fit the replacement electrode assembly

Disconnect electrical connections

Pull off the sensing tube from the air pressure switch

Note the setting of the old pressure switch

Remove the screws fixing the air pressure switch and remove switch

Installation of New Pressure Switch

Fit replacement in reverse order

Refit the sensing tube to the negative (- or L) tapping on the pressure switch

Disconnect the electrical connections to the centrifugal fan section

Remove the side panels of the section for access to the fan and motor

Fit replacements as appropriate

Is the direction of rotation correct for the 3-phase motor?

Interchange any two of the three phases if the direction of rotation is incorrect

Remove the burner assembly as described in Section 7.2

Remove the end plates of the burner assembly

Remove the central burner support plate

Reassemble components in reverse order