Heat recovery coils capture energy from hot condensate, boiler blowdown, and process waste streams, pre-heating makeup water, combustion air, or process fluids. Their tubes and fins are subject to fouling, corrosion, and thermal fatigue, requiring periodic replacement.
AQ Process Systems sources and exports replacement coil bundles, individual finned tubes, headers, and all associated control and safety devices for heat recovery systems used in industrial steam plants. We support both steam-heated and liquid-heated coil configurations.
Maintaining heat recovery equipment ensures maximum energy efficiency, a fouled or leaking coil wastes energy and can contaminate the heated fluid. We supply parts to keep your heat recovery systems performing at design efficiency.
| Component | Specification | Description |
|---|---|---|
| Coil Components | ||
| Coil Bundles | CS, SS, or CuNi tubes | Al or SS fins | Complete assemblies | Complete replacement coil bundles, finned tube assemblies with headers, ready for installation. |
| Individual Finned Tubes | L-footed, embedded, or welded fins | Individual replacement finned tubes for partial re-tubing of heat recovery coils. |
| Headers & Return Bends | CS or SS | Welded or bolted | Coil header boxes and return bend assemblies, providing fluid distribution and multi-pass configuration. |
| Tube Plugs | Taper or shoulder type | CS or SS | Tube end plugs for isolating leaking tubes as a temporary repair before full coil replacement. |
| Control & Safety | ||
| Control Valves | Globe or butterfly | 2-way or 3-way | Modulating | Temperature control valves regulating the heating medium flow through the coil, maintaining outlet temperature. |
| Steam Traps | F&T or inverted bucket | Sized for coil load | Condensate removal traps downstream of steam-heated coils, properly sized for the coil steam load. |
| Air Vents | Thermostatic | Automatic air release | Automatic air vents removing non-condensable gases from the coil, preventing air-binding and poor heat transfer. |
| Vacuum Breakers | Spring-loaded or float type | Vacuum breakers preventing coil collapse during steam supply interruption or rapid cooldown. |
| Accessories | ||
| Temperature Sensors | RTD or thermocouple | With thermowells | Inlet and outlet temperature sensors for monitoring coil performance and controlling output temperature. |
| Gaskets & Flanges | Various | Coil connection gaskets | Connection gaskets and companion flanges for interfacing coils with piping systems. |
Parts are matched to OEM material specifications and dimensional tolerances. Please provide the equipment manufacturer, model number, and serial number (if available) for precise part identification.
The most common spares are complete coil bundles (when fouling or corrosion makes cleaning impractical), individual finned tubes (for partial re-tubing), control valves (seat wear and actuator failure), steam traps (if steam-heated), air vents (blockage), and temperature sensors. Gaskets are replaced during every coil removal.
Indicators include reduced outlet temperature (fouling or air-binding), visible leakage at tube joints or headers, increasing pressure drop across the coil (internal fouling), and excessive plugged tubes (reducing effective surface area). If more than 10-15% of tubes are plugged, replacement is usually more economical than continued operation.
Yes. We can supply replacement coil bundles with upgraded materials (e.g., SS instead of CS for corrosive condensate), increased fin density for higher heat recovery, or modified connection sizes for system upgrades. Provide the existing coil dimensions and duty parameters for sizing.
Air-binding occurs when non-condensable gases (air, CO2) accumulate inside the coil, displacing the heating medium and creating dead zones with no heat transfer. This is common in steam-heated coils where air enters during startup. Automatic air vents at the highest point of the coil prevent this problem.
Yes. Steam-heated coils need properly sized condensate removal traps, typically float & thermostatic (F&T) type for modulating steam applications. The trap must be sized for the coil's maximum condensate load, including a safety factor for startup loads which can be 2-3 times the running load.
Share your equipment make, model, and part numbers, we respond within 24 hours.