This tender invites qualified contractors in Karachi for the operation and maintenance of HVAC chiller plants and allied equipment at the National Bank of Pakistan Head Office. The scope includes servicing wall mounted and floor standing air conditioning units, ensuring optimal performance over a three-year contract period. The work demands expertise in HVAC systems, focusing on efficient cooling solutions in a high-rise commercial building environment. Bidders must hold a valid Pakistan Engineering Council license in category C4/O4 or above with specialization code ME-01. The contract requires adherence to technical specifications and compliance with FBR and Sindh Revenue Board tax regulations. The tender emphasizes the importance of Earnest Money submission via original bid security instruments before the online bid deadline. Prospective bidders should ensure their PEC category and ATL status are current for the fiscal year 2025-26. This is crucial for eligibility and smooth processing. The tender follows strict PPRA rules, including the formation of a Grievance Redressal Committee as per Rule-48. Submission deadline is set for 11:00 AM on **February 6, 2026**, with bid opening at 11:30 AM the same day at the Engineering Wing, 3rd Floor, NBP Head Office, I.I. Chundrigar Road, Karachi. Manual bids are not accepted; all submissions must be through the EPADS online portal. Pro-Tip: Make sure to submit the original bid security instrument physically before the deadline, as failure to do so will result in bid rejection regardless of online submission. Also, attend the pre-bid meeting on January 27, 2026, at 11:00 AM to clarify any technical queries and avoid common pitfalls.