Residential Hydronic Heating Brochure

12
AL AR
BL BR
CL CR
AB
*
ZL ZR
www.runtalnorthamerica.com
Table 2
Calculating BTUH Output for
Different Water Temperatures
Please note: The BTUH outputs listed
in this catalog are based on 180°F
water. The following chart may be used
for calculating the BTUH outputs for
different water temperatures.
Water
Temperature:
120°
130°
140°
150°
160°
170°
180°
190°
Multiply listed
BTUH by:
.38
.48
.57
.67
.78
.89
1
1.13
A Step-by-Step Process for
Choosing Your Runtal Radiators:
1. You must choose a closed loop hydronic heating system. Hydronic heat has
many advantages over forced-air heating systems in terms of comfort, energy savings
and controls. A hydronic heating system is comprised of a boiler that heats hot water
and transfers this thermal energy through pipes to the radiators.
2. The heat requirement per room must be determined. This calculation,
measured in BTUH should be done by either a heating contractor or qualified
plumber. Because of the many variables involved in calculating a building’s heat loss
(R-value of insulation, region of the country, weather conditions, etc.) a professional
should confirm the actual BTUH requirements. Table 1 provides good heat
requirement estimates for different areas of the country.
3. Decide on the radiator style and desired placement. Decide where you want
to place the radiators. Placement of the radiators under windows or on outside walls
is optimal as this is where the heat loss is greatest.
4. Determine the height and length available. Divide the BTUH requirement for
the room by the total wall space chosen for radiator placement. This will establish
the BTUH per foot required. Select a model which has a BTUH per foot within
+/-10% of the level calculated. The outputs in this brochure are based on a water
temperature of 180 degrees. BTUH outputs at other water temperatures may be
calculated by using Table 2. In general the use of a lower water temperature is more
energy efficient.
5. Choose piping configuration. The radiators must be connected to the boiler.
Radiators can either be piped in a series loop (one radiator piped to the next radiator)
or individually off the main pipes. The most common piping connections are either
from the bottom or side of the radiator or combination of both. All baseboards and
wall panels unless specified otherwise, are manufactured with AB tappings. This allows
the flexibility to pipe in multiple ways (see Table 3). Runtal also offers rear piping and
supply and return on the same side as options. Specifications may be downloaded
from Runtal’s website.
Table 1
Heat Requirements
Sample Cities*
City:
Boston
Chicago
Denver
New York City
Philadelphia
Portland, OR
San Francisco
Seattle
Toronto
Washinton, D.C.
BTUH per sq. ft.:
40
40
40
40
35
25
25
25
40
35
Table 3
Popular Piping Configurations
* Estimates only
AL AR
BL BR
CL CR
AB
*
ZL ZR
Bottom
Bottom
and
Side
Side
Same
Side
Rear
Other Piping Options
* Allows for all types of A&B piping.
Flush plugs are included for closing off
the unused tappings.