Slant/Fin SX-150, S-150, SX-210 Sentry, Boiler Room Air Supply And Ventilation, Water Piping

8 Sentry

BOILER ROOM AIR SUPPLY AND VENTILATION

An ample supply of air is required to obtain combustion and ventilation. ALL AIR COMES FROM OUTSIDE, directly through wall openings to the boiler or through unsealed openings around windows, doors, etc. in the whole building. When build- ings are insulated, caulked and weather stripped, now or later on, direct openings to outside may be required and should be provided. If the boiler is not near an outside wall, air may be ducted to it from outside wall openings.

Provisions for combustion and ventilation air must be made in accordance with section 5.3, Air for Combustion and Ventilation, of the National Fuel Gas Code, ANSI Z223.1-latest edition, or applicable provisions of the local building codes. The following recommendation applies to buildings of energy-saving construction, fully caulked and weather stripped:

Provide one GRILLED opening near the floor and one near the ceiling on an outside wall near the boiler (or duct from such openings to the boiler), EACH opening to be a minimum of one square inch per 2000 Btuh input to ALL APPLIANCES in the area. For a total appliance input of 200,000 Btuh, each open- ing will be 100 square inches. A grilled opening 10"X10" has 100 square inches of area. If fly screen must be used over openings, double the area and inspect and clean the screen frequently.

Openings must never be reduced or closed. If doors or win- dows are used for air supply, they must be locked open. Protect against closure of openings by snow and debris. Inspect frequently.

No mechanical draft exhaust or supply fans are to be used in or near the boiler area.

The flow of combustion and ventilating air to the boiler must not be obstructed.

WATER PIPING

I.CIRCULATING SYSTEMS

A.Packaged water boilers are equipped with a water circu- lating pump, mounted to return the water into the boiler. For some installations, the pump should be on

the supply main. See figure 10.

II.AIR CONTROL SYSTEM

A.DIAPHRAGM-TYPE COMPRESSION TANKS are used to control system pressure in an AIR ELIMINATING SYS- TEM: an automatic air vent is used to REMOVE air from the system water. See figure 10. If system pressure needs further control, add an additional tank or install a larger capacity tank. Locate the tank near the boiler, as illustrated.An automatic air vent should be installed in the top of the boiler or air purger. See figure 10.

B.PUMP LOCATION — Locating low-head pump(s) on return to boiler is acceptable for smaller boiler sizes in residences of one or two stories. The alternate pump location shown in illustration is required in large, multi- story building installations, especially when high-head pumps are used. The compression tank must be at the boiler or between boiler and supply main pump(s).

IMPORTANT: Hot water heating systems containing high water volume, such as would occur with cast-iron radia- tion, require special care with air elimination.

The circulator pump should be located on the boiler sup- ply pipe and the expansion tank and air scoop should be located near the pump suction.

C.On a hot water boiler installed above radiation level, the boiler must be provided with a low water cutoff device at the time of installation by the installer.

Figure 10. Piping Arrangement

D. Radiant floor and low water temperature systems: A boiler by pass loop, three way valve arrangement, or prima- ry secondary pumping (with a boiler loop) must be used to pro- vide a minimum 130˚F return water temperature to the boiler. This will prevent condensation on the cast iron sections that can result in improper operation of the boiler.

OPERATING INSTRUCTIONS

I.FILLING AND VENTING WATER SYSTEMS

A.Fill the system with water. Vent or purge off air.

B.Fire the boiler as soon as possible (see following warning and instructions) and bring water temperature to at least 180 degrees, while circulating water in the system.

C.Vent air and add water as needed to achieve operating pressure on boiler gauge. Pressure must be between approximately 12 psi (cold water) and 25 psi (at water tem- perature setting of high limit control), for boilers equipped with 30 psi relief valves. Boilers rated for a higher pressure and equipped with a matching relief valve may operate at a higher pressure, but no higher than 5 psi below the relief valve opening pressure.

D.Check for and repair any leaks before placing system in service.

Before firing boiler, make these checks:

1.System is full of water. Air is vented or purged.

2.Relief valve is installed in accordance with the ASME Boiler Pressure Vessel Code, Section IV. Valve opening is not closed or reduced in size.

3.Venting is installed according to instructions under “VENT PIPING”.

4.All wiring is completed, following applicable wiring dia- grams.