Extension Cord Guidelines - PHP Heat Wagon LVF90A Service Manual

Oil fired heaters

Table of Contents

Connect heater to a standard electrical outlet (120V/60Hz) to operate. For safety, all

heaters have a three-prong, grounded power cord. Plug power cord of heater into

threeprong, grounded extension cord. Extension cord must be at least six feet long.

Make sure you use extension cord large enough to carry the voltage the heater requires.

Use the following chart to determine the proper size extension cord for heater.

Length of Cord Wire Size (AWG)

100 ft.

200 ft.

300 ft.

This section deals with calculating how much heat or BTU's a given job

needs. Usually a job requires the most heat at the beginning of construction when the

building is open. As the construction proceeds the building becomes more closed and

the heat requirement becomes less and less.

To calculate the BTU's needed you must first know three things:

1. The cubic feet of the area to be heated. Cubic feet is obtained by multiplying the

length times the width, times the height.

2. The "design temperature" of the location. Design temperature may be thought of as

the lowest possible temperature that will be encountered. This usually occurs at night.

The design temperature will vary greatly from one part of the country to another. For

example, the design temperature for Chicago Illinois is -10 degrees farenheight, com-

pared to Tampa Florida of 36 degrees.

3. Temperature rise desired. The temperature rise is the difference between the design

temperature and the temperature you wish to reach inside. Using Chicago Illinois as

an example if we wish to reach 60 degrees we must go from -10 to 60 for a tempera-

ture rise of 70 degrees.

Once we know the cubic feet, the design temperature and the desired temperature

rise, we can use the following formula:

Cubic feet x temperature rise, x .133 = BTU's required

Example:

Building size: 50 ft length x 25 ft width, x 12 ft height, = 15,000 cubic feet.

Chicago Illinois design temperature: -10 degrees.

Desired temperature: 60 degrees.

Temperature rise: from -10 to 60 degrees = rise of 70 degrees.

Using the formula we have:

15,000 x 70, x .133, = 139,650 BTU's required.

Placement of heaters.

Place your heaters so they are near the power supply. Because heaters add moisture

and products of combustion to the air inside the building, they should be placed in a

doorway, window, or opening, so the heater can draw fresh outside air into the build-

ing. In a multi-story building, place heaters in the lower levels because hot air rises.

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