Commercial SPA Blower Selection Guide
Posted by Optimal Tech on
Due to the amount of information included in this article we have provided a breakdown of the information below.
- Installation of Rotron Blower
- Requirements
- Number of Jets Chart
- Recommended SPA Chart
- System Requirement per Motor Chart
- Sizing Air Agitation Unit Overview
- Open Hole Area Formula
- Water Depth/Open Hole Blower Selection Chart
- Rotron Ready Spa Solutions Overview
- Features and Options
- Available Accessories
- Rotron Ready Spa Solutions Options
- Dimension Chart
- With Links to Available Rotrons
- Specifications Chart
- With Links to Available Rotrons
- Final Notes
SPA System Requirements
There are many variables that must be considered when selecting a blower for spa agitation. The depth of the spa, the size, quantity and location of the air holes and/or jets, and the size and length of the supply line are all important. The requirements of each and every system can be precisely calculated, but this is a long and tedious process. By defining and limiting several of the system parameters, a “standard” selection chart can be created. Blower Selection Chart 1 gives the maximum spa size that can be supplied by each blower.
| Blower Size | Number of Jets |
| DR404 (1 HP) | 3-6 |
| DR513 (1.5 HP) | 5-10 |
| DR454 (1.5 HP) | 5-10 |
| DR505 (2 HP) | 8-12 |
| DR656 (3 HP) | 12-17 |
Max Recommended SPA Surface Area
| Spa Depth | DR404 (1HP) | DR513 (1.5HP) | DR454 (1.5HP) | DR505 (2HP) | DR656 (2HP) |
|
30" |
60 SQ FT | 74 SQ FT | 88 SQ FT | 100 SQ FT | 135 SQ FT |
| 36" | 50 SQ FT | 68 SQ FT | 82 SQ FT | 95 SQ FT | 125 SQ FT |
| 42" | 45 SQ FT | 64 SQ FT | 76 SQ FT | 90 SQ FT | 115 SQ FT |
| 48" | 0 SQ FT | 58 SQ FT | 68 SQ FT | 85 SQ FT | 110 SQ FT |
Chart 3 - Drilled Holes
System Requirements by Blower Size
| All Blowers Listed | Supply and bubbler pipe to be 2.0 inch l.D. or greater. Supply pipe to be no longer than 25 ft. with no more than six elbows. |
| DR404/DR513 | Total hole area must be 1.0 square inches or greater but not greater than the cross section of the supply pipe. |
| DR454 | Total hole area must be 1.5 square inches or greater but not greater than the cross section of the supply pipe. |
| DR505 | Total hole area must be 2.0 square inches or greater but not greater than the cross section of the supply pipe. |
| DR656 | Total hole area must be 2.4 square inches or greater but not greater than the cross section of the supply pipe. |
Total hole area = (number of holes) X (.785) X (hole diameter)2 or
Total hole area = (number of holes) X (hole area)
SIZING YOUR SPA’S AIR AGITATION UNIT
The open hole charts provide a quick and easy method of sizing a spa blower. The chart is used when holes (not jets) are used. Simply find the total open hole area (see formula below), and then with the water depth in inches (Y axis of the chart), move across the chart until the water depth intersects with the total open hole area curve and find the blower that is closest to the intersection of water depth and open hole area.
Total open hole area (in square inches) = # of holes X ( 3.14 X (diameter) X (diameter) ) / 4
ie. a spa with twenty 1/4” dia holes has an open hole area of .98 sq inches.
Ex. A spa with water 40 inches deep, with twenty 1/4” diameter holes would require a DR656 blower
ROTRON Ready SPA Solutions
FEATURES
• Manufactured in the USA-ISO 9001 and NAFTA compliant
• CE Compliant-Declaration of Conformity on file
• Maximum Flow: 105, 127, 160, 200 or 78 SCFM
• Maximum Pressure: 56, 58, 74, 69, 88 IWG
• Standard Motor: 1.0, 1.5, 2.0, 3.0 HP, SPA Duty ODP
• Cast aluminum blower housing, impeller & cover; cast iron flanges (Threaded)
• Approved motor with permanently sealed ball bearings and Class B rated thermal protection
• Inlet and outlet internal muffling
• Quiet operation within OSHA standards
MOTOR OPTIONS
• Internal voltage and frequency (Hz)
• Chemical-duty, high-efficiency, inverter-duty or industry-specific designs
• Various horsepower for application-specific needs
BLOWER OPTIONS
• Corrosion-resistant surface treatments and sealing options
• Slip-on or face flanges for application-specific needs
AVAILABLE ACCESSORIES
| Filtration | Inline filter | Protect blower from dust and airborne contaminants |
| Measurement | Air Flow Meter | Optimize Efficiency |
| Noise Reduction | Inlet/Outlet Muffler (Single Connection) | Lower blower noise for pressure and vacuum systems |
| Valves and Gauges | Pressure Regulating Diaphragm Valve | Prevent excessive system pressure or vacuum that could result from line restrictions |
| Valves and Gauges | Pressure Regulating Diaphragm Valve | Prevent excessive system pressure or vacuum that could result from line restrictions |
ROTRON Ready Spa Solutions
Dimension Chart
| DR404AQ58M | DR454V58 | DR505AW58M | DR513V58 | DR656K58X | |
| A(IN/MM) | 4.75/120.7 | 4.75/120.7 | 4.75/120.7 | 4.75/120.7 | 4.92/125 |
| B(IN/MM) | 8.93/226.8 | 10.30/231.6 | 10.30/231.6 | 11.42/290.1 | 11.42/290.1 |
| C(IN/MM) | 10.12/257 | 11.39/289.1 | 11.70/298.2 | 13.0/330.2 | 12.8/325.1 |
| D(IN/MM) | 1.92/48.8 | 1.92/48.8 | 1.87/47.5 | 2.23/56.6 | 2.25/57.2 |
| E(IN/MM) | 6.28/159.5 | 6.98/177.3 | 7.26/184.4 | 8.69/220.7 | 7.46/189.5 |
| F(IN/MM) | 11.5/292.1 | 12.55/318.8 | 13.53/343.7 | 12.21/360.9 | 15.42/391.7 |
| G(IN/MM) | 12.16/308.9 | 13.52/343.4 | 14.38/365.3 | 15.8/401.3 | 15.17/385.3 |
| H(IN/MM) | 3.0/76.2 | 3.25/82.6 | 3.56/92.7 | 3.72/94.5 | 4.14/105.2 |
| I(IN/MM) | 3.75/95.3 | 4.50/114.3 | 4.50/114.3 | 5.50/139.7 | 5.50/139.7 |
| J(IN/MM) | 12.88/372.2 | 10.81/274.6 | 14.38/365.3 | 13.74/349 | 15.12/384.1 |
| K(IN/MM) | .59/15 | .59/15 | .59/15 | .59/15 | .59/15 |
| L(IN/MM) | 12.91/327.9 | 14.45/367 | 15.0/381 | 14.58/370.3 | 15.51/393.9 |
Specification Chart
| DR404AQ58M | DR454V58M | DR505AW58M | DR513V58 | DR656K58X | ||
| Specification | Units | 037778 | 080485 | 037935 | 038143 | 080603 |
| Motor Enclosure - Shaft MTl | - | SPA(ODP)- CS | SPA(ODP)- CS | SPA(ODP)- CS | SPA(ODP)- CS | TEFC-CS |
| Horsepower | - | 1.0 | 1.5 | 2.0 | 1.5 | 3.0 |
| Voltage | AC | 115/230 | 115/230 | 115/230 | 115/230 | 115/230 |
| Phase | - | Single | Single | Single | Single | Single |
| Frequency | - | 50/60 Hz | 50/60 Hz | 50/60 Hz | 50/60 Hz | 50/60 Hz |
| Insulation Class | - | F | F | F | F | F |
| NEMA Rated Motor Amps | Amp(A) | 15/7.5 | 15.2/7.6 | 17.6/8.8 | 15.2/7.6 | 31/15.5 |
| Service Factor | - | 1.4 | 1.3 | 1.2 | 1.3 | 1.0 |
| Maximum Blower Amps | Amp(A) | 8/4 | 17/8.5 | 26/13 | 17/8.5 | 27.8/13.9 |
| Locked Rotor Amps | Amp(A) | 32/16 | 85/43 | 106/53 | 85/43 | 200/100 |
| Recommended NEMA Start | r Size | 0/00 | 1/0 | 1/0 | 1/0 | 1.5/1 |
| Shipping Weight | LBS/KG | 64/29 | 76/34.5 | 83/37.6 | 90/40.8 | 51/23.1 |
| Recomended Number of Jets | ts- | 3-6 | 5-10 | 5-10 | 12-17 | 8-12 |
Voltage - ROTRON motors are designed to handle a broad range of world voltages and power supply variations. Our dual voltage 3 phase motors are
factory tested and certified to operate on both 208-230/415-460 VAC-3 ph-60
Hz and 190-208/380-415 VAC-3 ph-50 Hz. Our voltage 1 phase motors are
factory tested and certified to operate on both 104-115/208-230 VAC-1 ph-60
Hz and 100-110/200-220 VAC-1 ph-50 Hz. All voltages above can handle a
±10% voltage fluctuation.
Special wound motors can be ordered for voltages outside our certified range.
Operating Temperatures - Maximum operating temperature: Motor
winding temperature (winding rise plus ambient) should not exceed 140°C
for Class F-rated motors or 120°C for Class B-rated motors. Blower outlet air
temperature should not exceed 140°C (air temperature rise plus inlet temperature).
Performance curve maximum pressure and suction points are based
on a 40°C inlet and ambient temperature. Consult factory for inlet or ambient
temperatures above 40°C.
Maximum Blower Amps - Corresponds to the performance point at which
the motor or blower temperature rise with a 40°C inlet and/or ambient
temperature reaches the maximum operating temperature.
Notes
- The blower should not be stopped/started more than four times an hour.
- Use of relief valve 515092 is required for all blowers 2 HP or greater.
Information provided by Ametek DFS