Patterson-Kelley MACH-05 manual Boiler Water Piping by Installer, Flushing and Filling

MACH® Series Gas-Fired Boiler

3.8.3 Boiler Water Piping by Installer

Strainer

To avoid possible contamination of the boiler with dirt, rust or sediment from the system, a strainer near the boiler inlet is strongly recommended. Even new systems may contain sufficient foreign material to eventually reduce the performance of the heat exchanger. Adequate circulation of good clean water is essential to maximum efficiency and long life of the boiler.

Relief Valve and Piping

Each boiler is supplied with a pressure-relief valve sized in accordance with ASME requirements. The relief valve should be piped to a suitable floor drain. Reducing couplings or other restrictions are not permitted in the discharge line.

Low Water Cut-off

The boiler is furnished with a probe-type low water cut-off; no field piping is required. If the water level in the boiler drops below the probe, the boiler will shut down and a flashing E 12 service code will be displayed on the control panel. The low water cutoff circuit will automatically reset when the low water condition clears; however the boiler controls will retain the lockout condition until the reset button on the display is depressed.

IMPORTANT!

The low water cutout probe only prevents boiler operation when the water level in the boiler is insufficient. It does not detect low water conditions in other parts of the system. Installation of high point vents or additional low water safety devices to protect the system should be considered.

Installation of external limit controls may be required by certain codes or in certain installations. Review applicable local codes for details.

Installation

Drain Valve and Piping

A drain valve is installed in the inlet (system return) header connection to the boiler. Prior to draining the boiler for maintenance or testing, electrical power and gas supply must be turned off to the boiler. The boiler must then be isolated from the system at the supply and return connections prior to draining water from the boiler.

Note: This drain valve is installed for draining of the boiler water only, not the entire system. Draining of the system through the boiler will result in depositing sediment from the system in the boiler which will result in poor heat transfer characteristics of the boiler and early boiler failure.

Condensate Drain

The condensate can be slightly acidic (pH between

3.0and 5.0). This may be corrosive to some building drain systems. A condensate neutralization system may be required.

Disposal of condensate must comply with all state and local codes.

3.8.4 Flushing and Filling

Water Quality

The MACH Series boiler heat exchanger is made of an aluminum alloy. The heat exchanger requires special water conditions to retain efficiency and function properly.

IMPORTANT!

Chemicals added to the system must be approved by the chemical manufacturer for use in aluminum boilers.

IMPORTANT!

Under no circumstances should petroleum based cleaning or sealing compounds be used in the boiler system.

The boiler is designed to operate in a closed-loop system. As such, the system should be tight and not require make-up water. A high percentage of

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