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How To Retrofit A Tiger River Spa: Step-by-Step

Blog Featured Images 31-

Welcome to Backyard Plus! In this blog, we are going to show you how to retrofit a Tiger River spa with the 76836 Eagle control box, the 76845 control panel, 79005 and 79006 thermistors, and the 74930 main LED light. This is not an easy job because it requires cutting a larger opening in the bartop of the spa but, if you have some mechanical ability and follow the directions carefully, this retrofit will be very rewarding. Before we get started, let’s get a list of the tools you will need.

Tools you will need to retrofit a Tiger River spa:

  • Phillips head screwdriver
  • Flat head screwdriver
  • Needle nose pliers or vice grips
  • Putty knife or scraper
  • Hand-held trim router (Drill Master 1/4” Trim Router)
  • Black Sharpie
  • Dow 839 silicone adhesive sealant
  • Caulking gun
  • Crescent wrench
  • Shop Vac
  • Wire cutters

Steps to Retrofit a Tiger River Spa

Step 1: Break the adhesive seal around the control panel with your putty knife.

1. Control head removal putty knife-

Step 2: Disconnect the ribbon cable from the motherboard and remove the control panel from the spa.

3. unplug the ribbon-
2. remove from spa 1-

Step 3: Using your putty knife, remove the old adhesive from the bar top.

4. Scrape the bartop-

Step 4: Remove the back cover of the new control panel to use as a guide for measuring the new opening you are going to cut.

5. Remove the back cover 1-

Step 5: Place the control panel cover on the bar top and trace a line around the entire edge of the cover using your Sharpie.

6. Mark it with a Sharpie-

Step 6: Put on your safety glasses and Install a 3/4” straight router bit in your Drill Master ¼” trim router.

7. Safety glasses-
8. straight router bit-

Step 7: Cut a new opening in the bar top by carefully cutting along the lines.

9. Cut the opening-

Step 8: Check the fitment of the new control panel. Make certain it fits snugly in the new opening.

10. Check the fitment-

Step 9: Remove all debris from the bar top with your shop vac.

Prepare the surface of the bar top around the new opening by scrubbing it with soap and water. Remove all dirt and debris from the area you are going to seal.

11. Clean the bar top-

Step 10: Prepare the Dow 839 silicone adhesive.

12. place the DOW in the caulk gun-

Place the Dow 839 silicone adhesive in the caulking gun and puncture the seal.

13. punch a hole-

Place a ¼” wide bead around the entire perimeter of the underside of the control panel.

Push the control panel cable down through the opening and into the equipment compartment. Press the control panel down firmly on the bar top to make a good seal. Use a paper towel to clean up any excess silicone on the bar top around the control panel.

14. Silicon the panel-
15. Install the new panel-

Step 11: Open up the IQ 2020 control box and disconnect everything.

Disconnect the sensors, spa light, ozone, circulation pump, jet pump heater, incoming power, and bonding wires. Remove the two bolts that hold the control box to the mounting bracket. Remove the control box from the spa.

16 disconnect the IQ2020 box-
17 Remove the IQ2020 box from the tub-

Step12: Remove the old spa light and install the new 74930 LED light.

Remove the old spa light by simply pulling the LED light housing away from the mounts on the wall. Remove the old LED light from the housing and install the new 74930 LED light in the housing. Line up the mounting holes and press the LED light housing back onto the wall. If your light is the old-style flood lamp, you will need to zip tie the new LED light to your existing spa light heat guard.

18 Remove the old light-
19 Install the new light-
20 Mount the LED light in the spa-

Step 13: Install the new 76836 Eagle box by securing it to the bracket with the two mounting bolts.

21 Install the new Eagle box updated-

Step 14: Remove the old thermistors from the heater and install the new ones.

22 Remove old sensors best-
23 Istall new sensors best-

Step 15: Remove the heater ground flag post from the old heater relay board and install it on the new one.

24 Remove ground flag post from old box-
25 Install heater grounf flag post on new box-

Step 16: Connect the green heater wire to the heater ground post and the black and white heater wires to HI and H2.

26 plug in heater ground and H1 and H2-

Step 17: Plug the control panel connector into the control head port.

27 Plug in control head-

Step 18: Plug in the control and high-limit sensors.

Route the control and high-limit sensors through the side of the control box and plug them into the appropriate ports. The 4-pin connecter plugs into the REG THERM port. The 2-pin connector plugs into the LIMIT THERM port. Make sure you plug the sensors in correctly, otherwise the power and ready lights will flash and the heater and jet pump will not operate. 

28 Plug in sensors-

Step 19: Plug in the LED spa light.

Plug the adapter into the spa light cable and route the LED spa light cable through the side of the control box. Plug the spa light into zone 1 on the motherboard.

29 LED spa light adapter-
30 plug in spa light to zone1-

Step 20: Plug in the jet pump, circ pump and ozonator.

Push the jet pump, circ pump, and ozone cables up through the bottom of the control box and secure each one with a strain relief clamp. Plug them into the appropriate terminals on the motherboard.

31 plug in jet and circ pump-

Step 21: Connect the incoming power.

In this blog we have wired the spa to run on 120 volts. Make sure you have a jumper between terminals 6 and 7.  You must also have a jumper between terminals 4 and 5. Last but not least, you need a wire jumper between terminals 2 and 6. Secure the green ground wire to the ground lug.

Using your small flathead screwdriver, press down on the tab (just above where the wire goes in) and push the white neutral wire into terminal 7. Push the black hot wire into terminal 4. Make sure all the wires are securely fastened to the terminal block.  (See the instructions on your control box lid for wiring 240 volt convertible spas and 240 volt permanently connected spas).

32 power jumpers-
33 Jumper wire between 2 and 6-
34 Incoming 120v power-

Step 22: Install the pressure switch jumper 72768 on the pressure switch port.

35 Jump the pressure switch-

Step 23: Install the IQ 2020 box lid and connect the copper bonding wires to the bonding terminal.

36 Install the IQ lid best-
37 Connect the bonding wires-

Watch the video here on How to Retrofit A Tiger River Spa!




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