Hayward Spa Blower - New Spa Applications; Blower Replacement - Existing Spa

USE ONLY HAYWARD GENUINE REPLACEMENT PARTS
Page 9 of 12 Spa Blower ISSPB Rev-A
6. New Spa Applications
a. Determine the number of water jets required in your spa. Next choose the correct size water
pump - the water jet manufacturer will supply horsepower per-jet guidelines to help you
choose. Loop air line above water level as per Diagram #2. It is important to size the water
pump correctly for the number and size of water jets in your spa. Improper sizing can
cause both blower and water pump to overheat and or water to back up into the
blower.
b. Choose the correct size blower based on the number of water jets in your spa. See
the chart below. Note that you may require a larger blower if your installation
differs significantly from the standard installation. Please refer to the installation
guidelines for more details.
BLOWER SIZE VOLTS AMPS NUMBER O
F
WATE
R
JETS
1 HP 120
/
2
4
06.
7/3
.
5
4
TO 8
1.
5
HP 120
/
2
4
08.0
/4
.0 8 TO 12
2.0 HP 120
/
2
4
010.0
/
6.0 1
4
OR MORE
7. Blower Replacement – Existing Spa
Determining the size of blower for an existing spa is more difficult since many factors including length of
supply line and number of 90 degree turns are unknown under concrete and decking.
a. Use the sizing chart above as a good starting point based on standard installation.
b. Check the size of the water pump and see if it is sized correctly based on the number of water jets.
A good rule of thumb is 1/4 hp for every water jet. Run the water pump without the blower and check
the air line for signs of water backing up.
c. Allow the blower to run for 30 minutes and check that air is exiting all water jets.
d. Use a Magnehelic pressure gauge (0-100 inches) to measure back pressure while blower is
operating. See trouble shooting guidelines for complete details.