The FAT Playbook 

A Factory Acceptance Test (FAT) is a full-system run that shows how your temperature-control equipment performs before it leaves the factory. By operating the system at its specified temperature and, when appropriate, with the intended process fluid, HEAT can verify controls, safety interlocks, alarms, mechanical performance, and electrical operation under realistic conditions. Just as important, your team can see the equipment in action, ask questions, and prepare for a smoother installation and startup.

What Is a Factory Acceptance Test? 

A FAT is the final factory-based validation of a complete engineered system before shipment. HEAT operates the unit at its specified conditions, checks how the components work together, and documents the results. Depending on the application, the test may use the same fluid intended for the process to reduce contamination risk and produce representative performance data. 

You can witness the test in person or virtually. Either way, the FAT gives your operations, maintenance, controls, and safety personnel a chance to review the operating sequence, see customized features, and become familiar with safe operation and maintenance before the equipment reaches your facility. 

Why the FAT Matters 

Hot-oil systems operate at elevated temperatures, so sound design, proper control logic, and verified safeguards are essential. A FAT helps identify functional or integration issues while the equipment is still in the factory, where corrections are generally faster and less disruptive than troubleshooting after installation. 

It also gives HEAT, your team, your insurer, and your thermal-fluid supplier a common technical baseline before shipment. HEAT designs and fabricates to applicable codes and standards. During the FAT, we demonstrate safety interlocks, alarms, controls, and operating responses under load so you have documented evidence that the equipment was tested before delivery. 

Safety: Our First Core Value

How an In-Person or Virtual FAT Works 

We love hosting our customers here in Carnegie, and many attend the FAT at our facility at HEAT to see their equipment functioning for the first time. When travel isn't possible, however, your team members can join remotely through video conferencing sofware. A Virtual FAT allows people in one or several locations to watch the same test, ask questions, and participate without leaving their desk. When requested, the session can also be recorded for training, internal review, or future reference.

For a Virtual FAT, HEAT uses a live multi-camera setup, typically two to four cameras. We use one view to show the complete system, while a wireless handheld camera follows the inspection and moves in for close-ups. Additional cameras can stay focused on a temperature controller, pressure gauge, or another critical device. HEAT project and technical personnel remain available throughout the session to explain the operating sequence and answer questions in real time.

Typical Virtual FAT camera setups

• Two cameras: One wireless handheld camera for close-ups and one fixed system overview, often used for compact units.
• Three cameras: A handheld view, a dedicated instrument close-up, and a full-system overview. This is the most common setup.
• Four cameras: Multiple system angles plus dedicated close-ups, useful for larger systems where overhead and side views help keep viewers oriented.

Set the FAT Scope Before the Test 

A productive FAT starts with a clear scope. Before testing begins, you (our customer) and HEAT should align on the equipment included, operating conditions, test temperatures, required measurements, acceptance criteria, and customer witness points. Defining these items in advance keeps the test focused and provides a clear basis for deciding whether the system is ready for shipment.

What to Expect During the Test

Most of our systems are custom manufactured, so the exact procedure depends heavily on system design. Generally, however, a FAT follows this sequence:

• Introductions. HEAT’s project manager, engineers, and technicians introduce themselves and invite your team to do the same.
• System overview. Using the wireless camera during a Virtual FAT, the engineer follows the piping flow path, explains how the system will be filled on site, reviews test parameters, and points out critical components. 
• Electrical demonstration. The technician reviews controls and safety interlocks, demonstrates alarm and remote-control functions, and opens the control panel so your team can see the electrical system in operation. If the system includes a pump, the technician confirms flow by showing the pressure change at the pump gauge. 
• Heat-up. The temperature controller is set to call for heat, the system is brought to operating temperature, and data is recorded at regular intervals. 
• Additional demonstrations. Project-specific features, such as a cooling loop or alternate operating mode, are demonstrated according to the agreed FAT scope. 
• After the test. The system is cooled, drained, cleaned, painted, and insulated as required for shipment. Your project manager addresses final questions and coordinates delivery of the recording when one was requested.

WATCH:  A live demonstration for an NFP 500 Series system and modular CLBS Cooling Skid.

How to Prepare for the FAT 

A little preparation makes the FAT more useful as both a validation step and a training opportunity: 

• Confirm attendees and roles. It can be very useful to include the people responsible for operation, maintenance, controls, and safety approval in the virtual test. Let us know the list of attendees in advance so we can be sure to send the invites and links to the virtual meeting for those attending online.
• Identify must-see items. Flag custom components, operating modes, gauges, controllers, or interlocks that need focused review. We're happy to answer any questions that come up as the test progresses, but if there's a critical component that you'd like to focus on, we'd like to know.
• Confirm the test conditions. Verify the fluid, operating temperature, measurements, and other conditions included in the FAT scope.
• Prepare the site team. Use the system overview to capture the fill procedure, piping flow path, and startup considerations that will matter during installation.
• Plan for the recording. If you want the session recorded, identify the recipients and preferred delivery format in advance. If desired, we can edit the video to speed through heat-ups and cool-downs and make repeat watching more efficient.
• Bring applicable requirements. Have insurer, thermal-fluid manufacturer, and project-specific requirements available so the relevant items can be confirmed during the test.

What You Receive After the FAT 

Following the FAT, HEAT provides a System Test Report that records the checks performed, operating data collected, and adjustable settings established for the equipment. Depending on the system configuration and project scope, the report may include: 

• Pre-test checklist: Drawings and bills of material verified against the P&ID, with mechanical and electrical components confirmed by manufacturer, size, and rating. 
• Energization and interlock checkouts: Operational checks of pilot devices, pump and heater interlocks, level and pressure switches, high-temperature switches, and control valves. 
• Heating and cooling data: Bulk fluid temperature, discharge pressure, and motor amps logged by zone across the operating range. 
• Pump and heater data: Pump-curve flow rates, heater-circuit resistance, amp draw, and power output. 
• Bench-set values: Recorded set points for adjustable components such as pressure switches, regulators, back-pressure control valves, and flow switches.