GF User Defined Price Validation

add_filter( 'gform_field_validation_1_22', 'gf_user_defined_price_validation', 10, 4 );
function gf_user_defined_price_validation( $result, $value, $form, $field ) {
    //change value for price field to just be numeric (strips off currency symbol, etc.) using Gravity Forms to_number function
    //the second parameter to to_number is the currency code, ie "USD", if not specified USD is used
    $number = GFCommon::to_number( $value, '' );
    GFCommon::log_debug( __METHOD__ . '(): User Defined Price Submitted: ' . $number );

    if ( $result['is_valid'] && $number < 5501 ) {
        $result['is_valid'] = false;
        $result['message'] = 'You must enter less than $5500.00';
    }
    return $result;
}