Venting, Integral Draft Hood | PB Heat MIH specs

VENTING

4. VENTING

A.INTEGRAL DRAFT HOOD

1.The MI/MIH boiler is equipped with a built-in draft hood. This device is designed to:

a.provide for the ready escape of flue gases from the boiler in the event of no draft.

b.prevent a backdraft from entering the boiler.

c.control stack draft during operation.

These tasks are accomplished without the extra height requirements of a separate draft hood.

2.The draft hood relief opening is the large rectangular passage at the front of the boiler. Make certain that there are no obstructions to airflow in front of this opening.

3.A vent safety shut-off switch is located within the draft relief opening to shut off the boiler in case of a blocked vent condition. See Section 7B for details regarding this device. See Figure 6.1 in Section 6 (Electrical) for spill switch location.

4.The vent damper can be mounted directly onto the round draft hood outlet (vent connector) on top of the boiler, or in vent piping close to the boiler. See the Vent Damper Installation Instructions below.

Figure 4.1: Venting Multiple Appliances

B.VENT DAMPER INSTALLATION – GENERAL

1.Do not use one vent damper to control two or more heating appliances. See Figure 4.1.

2.Follow these and the installation instructions that are included with the vent damper. Observe the cautions and warnings that accompany all instructions.

3.Make certain that minimum clearances provided in the vent damper manufacturer’s instructions are maintained and that adequate space is available for damper access and service.

4.Orient the damper operator to facilitate connection of the harness with the vent damper and boiler. Note flue gas flow arrow on vent damper and orient as required. For installation with damper mounted in vertical position, see Figure 4.2. For installation with damper mounted in horizontal position, mount the unit as shown in Figure 4.3 to avoid excessive heat on the operator or condensation drips into the operator.