MECHANICAL INSTALLATION — EXHAUST SYSTEM

If the engine-generator is not equipped with a factory mounted exhaust system, such as a unit mounted inside a building or room, the installation of the engine exhaust system has to be planned very carefully. When installing an exhaust system on an open or un-housed generator, consider the following recommendations:

1.After a thorough review of the exhaust installation requirements, select the engine silencer, piping and exhaust fittings based on the engine manufacturer’s maximum exhaust backpressure limits.

2.Use flexible, corrugated stainless steel exhaust tubing, 12 to 18 inches (305 - 457 mm) in length, to connect the exhaust silencer to the engine exhaust outlet. This tube or flex connector allows for thermal expansion and engine vibration.

3.Be sure to support the exhaust system (muffler, piping, etc.) to minimize the total weight applied to the engine exhaust manifold and exhaust outlet elbow or turbocharger connection.

4.Exhaust piping should conform to NFPA 37, Stationary Engines and Gas Turbines design practices, and any applicable local codes.

5.Avoid sharp bends in the exhaust piping by using sweeping, long radius elbows and provide adequate support for muffler and all associated piping.

6.Pitch a horizontal run of exhaust pipe DOWNWARD to allow moisture condensation to drain away from the engine. If an exhaust pipe must be turned UPWARD, install a condensation trap at the point where the rise begins. See Figure 15 on page 48.

7.Shield or insulate exhaust piping if there is any possibility of personal contact. Allow at least 12 inches (305 mm) of clearance where piping passes close to a combustible wall or partition.

8.Use an approved, insulated & ventilated, metal thimble where exhaust pipes pass through a combustible wall or partition.

9.Always pipe exhaust gases to the outside of any building or room. Route the engine exhaust away from any building air inlets to avoid engine exhaust fumes from entering the building fresh air intake. Some codes specify that the exhaust outlet terminate at least 10-feet (3 meters) from the property line, 3-feet (1 meter) from an exterior wall or roof, 10-feet from openings into buildings and at least 10-feet above any adjoining grade.

10.The installation of a rain cap is required for the discharge end of the exhaust system piping, if the piping is vertical. The rain cap clamps onto the end of the pipe and opens from the exhaust discharge force from the generator set while running. When the generator set is stopped, the rain cap automatically closes, protecting the exhaust system from rain, snow, etc.

11.Once the exhaust system has been installed, it is important to regularly inspect the exhaust system both visually and audibly to see that the entire system remains sealed against leakage and safe for operation.

DO NOT use flexible tubing to form bends or to compensate for misaligned piping.

„Reduce corrosion from condensation by installing the muffler as close as practical to the engine.

„Support mufflers and piping by non-combustible hangers or supports. DO NOT use the engine exhaust outlet for support. Weight on the engine exhaust outlet can cause damage to the engine exhaust manifold or reduce the life of a turbocharger.

„Schedule 40 black iron pipe is recommended for exhaust piping.

„Pipe bend radius should be as long as practical.

„NEVER use exhaust tubing and piping of smaller diameter than the exhaust outlet. Verify the back pressure limitation of the engine, and use exhaust tubing and piping of the appropriate size throughout the exhaust system.

„DO NOT use piping that is larger than necessary to avoid corrosion from condensation. Doing so also reduces the exhaust gas velocity available for dispersing the exhaust gases up and away in the outdoor wind stream.

„Keep exhaust pipe diameter changes to a minimum to avoid friction and performance loss.

„A genset should not be connected to an exhaust system servicing other equipment, including other gensets. Soot, corrosive condensation, and high exhaust gas temperatures can damage idle equipment served by a common exhaust system.

INDUSTRIAL GENERATOR SETS — APPLICATION & INSTALLATION MANUAL — REV. #4 (09/07/07) — PAGE 47

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Multiquip MQP60GM, MQP20IZ, MQP40IZ, MQP45GM, MQP60IV, MQP50IZ, MQP30GM, MQP30DZ Mechanical Installation Exhaust System