UH-SVX01A-EN 29
Technical Data

Technical Data: P Model

The performance data listed in
Tabl e 1 3, Tab le 14, and Ta ble 15
include sound ratings. The ratings
provide a guide in determining the
acceptable degree of loudness in
particular occupancy situations.
Certain general rules apply to specific
selection of unit heaters with regard
to degree of quietness (or loudness);
• The greater the fan diameter, the
higher the sound level.
• The higher the motor RPM, the
higher the sound level. Note that
on most units the lower the
speed mode results in lowering
the sound rating one increment.
• Selecting a larger number of
smaller units generally results in
lower overall noise levels than
fewer large units.
All vertical steam and hot water unit
heater motors, whether fan guard or
shelf-mounted, are isolated from the
mechanical mount by resilient
isolators. This mounting along with
balanced fan blades and excellent
overall construction integrity, assures
you the utmost in quiet operation.
The following table outlines sound
ratings for various applications. The
lower the number, the quieter the
unit and the lower the sound
requirement.
* Depending on specific use in these facilities,
size of operation, etc.
*Compared to water.
Category of Area Sound Rating
apartment, assembly hall, classrooms, churches, courtrooms, executive
offices, hospitals, libraries, museums, theatres
I
dining rooms, general offices, recreation areas, small retail stores II
restaurants, banks, cafeterias, department stores, public buildings,
service stations
III
gymnasiums, health clubs, laundromats, supermarkets IV
garages, small machine shops, light manufacturing V
factories, foundries, steel mills III-VII*
Table 14. Corrections When Using Glycol Solution in System
Propylene
Glycol
Heat transfer @ 180°F with no
increase inflow rate
20% solution .97*
50% solution .90*
G.P.M. Req'd. @ 180°F, 20°F ∆ t (no
correction to pump curve)
1.10%*
Pump Head Req'd. @ 180°F w/
increase in G.P.M.
1.23%*
Specify gravity (water = 1.0) 1.045-1.055*
Pounds/Gallons @ 60°F (water =
8.3453 Pound/Gallon)
8.77
pH @ 50% by volume 9.5
Freezing Point by volume
55% -
50% -28°F
40% -13°F
30% + 4°F
20% +17°F
Table 15. Approximate factors at varying altitudes
Altitude Factor
Sea level - 1000 ft. 1.00
1000 ft. - 3000 ft. .958
3000 ft. - 5000 ft. .929
5000 ft. - 7000 ft. .900
7000 ft. - 10000 ft. .871