The Ombudsman has called for clearer guidelines on dealing with complaints about dripping air-conditioners at public housing estates, saying a lack of detailed instructions has led to cases being inconsistently handled.

In reporting detailed findings on the Housing Department's handling of leaking air-cons, the watchdog also said on Thursday authorities should better monitor the property management of public estates that had been outsourced to private firms.

Dripping air-conditioners are regarded as a misdeed under the administration's marking scheme for estate management enforcement at public flats, with repeat offenders accruing five penalty points.

According to the Office of the Ombudsman, the number of complaints received by housing officials dropped 93 percent from around 18,900 two decades ago to an average of about 1,300 annually in the past three years.

Public estates that had their property management outsourced to private firms saw 2,826 such complaints between 2022 and 2024, while those directly managed by the Housing Department received 1,049 in the same period.

"On average, property services agents issued two reminder letters per complaint received in outsourced estates, which was tenfold of those issued in directly-managed estates," the watchdog said.

There have been cases in which dripping problems continued to occur despite "repeated issuances of reminder letters".

The Ombudsman noted that it might be difficult for the Housing Department to gauge whether property-services agents are issuing too many reminder letters and determine whether there is any mishandling of air-conditioner dripping cases.

It suggested authorities consider introducing measures relating to issuing advisories and reporting cases.

The watchdog also called the department's operational guidelines on handling such complaints "rather brief", with no detailed instructions given to frontline workers.

Security staff closed one of the cases "solely based on a rooftop inspection without entering the flat in question to switch on and test the air-conditioner, which was not quite prudent," it said.

"Moreover, the estate management office failed to effectively deal with the tenant's repeated refusals for indoor testing," it added.

To that, the Ombudsman urged officials to provide clear procedures governing the investigation of dripping air-cons and to request frontline workers to conduct follow-up inspections.

In response, the Housing Department said it had introduced new measures in December 2024 that gave tenants five days to rectify any water dripping problem from their air-conditioners before it takes action under the public estate marking scheme.