National Oilheat Research Alliance 39
width of each heat emitter, count the number
of tubes or columns and count the number of
sections. Then use the appropriate charts to determine
the sq. ft. of radiation in each section.
For example:
Column radiators. This column
radiator has 3 columns
and is 32" high.
• The chart shows 4.5 sq.
ft. of radiation per section
(Figure 1, previous
page)
• There are 8 sections.
• 4.5 X 8 = 36 Sq. Ft. of radiation for this
radiator
Tubular radiators. The
sections of standard tubular
radiators are generally 2.5"
wide. This tubular radiator
has 4 tubes and is 38" high.
• The chart shows 4.25 Sq.
Ft. of radiation per section
(Figure 2, below)
• There are 10 sections
• 4.25 X 10 = 42.5 Sq. Ft. Of
radiation for this radiator
Radiant convectors. This
radiant convector is 5" wide
and 20" high.
• The chart shows that there
are 2.25 Sq. Ft. of radiation per section
(Figure 3)
• To determine the numberof sections, count
the number of openings between the sections
and add 1.
• This unit has 10 sections.
• 2.25 10 = 22.5 Sq.
Ft. of radiation for
this convector.
Cast iron baseboard.
This cast iron baseboard
is 10” high.
• The chart shows
that there are 3.4 Sq. Ft. of radiation per
linear foot. (Figure 4)
• Assume that 10 linear feet
are installed.
• 3.4 X 10 = 34 Sq. Ft. of
radiation for this section of
baseboard.
Figure 2
Figure 3
Figure 4