Welcome to Backyard Plus! In this post, we show you how to replace your old heater with a new PDR heater in a Hot Spring spa, Tiger River spa, and Limelight spa. If your heater is not heating and you have good voltage at H1 and H2 on your heater relay board, it’s a good bet you need a new heater. Before we get started, let’s determine which tools you will need.
Tools you will need:
- Phillips head screwdriver
- Small flathead screwdriver
- Wine corks ( if you are not going to drain your spa )
- Pliers
Step 1. Disconnect power from the spa.
Step 2. Drain the spa. ( or you can use wine corks to plug the ¾” heater hoses instead of draining the spa.)
Step 3. Remove the equipment door and gain access to the heater. In some cases, this may require moving the control box out of the way. In this video, we will remove the control box from the spa.
Step 4. Access the IQ 2020 control box and remove the lid. Using a small flathead screwdriver, disconnect the heater wires from H1 and H2 and the green ground wire from the grounding lug.
Disconnect the copper bonding wire from the bonding terminal.
Step 5. Unplug the REGTHERM and LIMTHERM thermistors from the motherboard. Unplug the pressure switch wire from the P34 pressure switch port ( if there is one plugged in ).
Step 6. Make sure the foot of the heater is disconnected from the floor of the spa.
Step 7. Loosen the bleed-line hose clamp on the back of the heater and remove the ¼’ hose.
Remove the inlet and outlet hose and quickly plug the hoses with the wine corks ( if you did not drain your spa ).
Step 8. Install the O-rings on your new PDR heater.
Step 9. Put silicone grease on the bleed-line nipple and the inlet and outlet barbed nipples for ease of installation.
Step 10. Thread the REGTHERM and LIMTHERM thermistors into the inlet and outlet of the new heater.
Step 11. Install the new heater. Connect the inlet and outlet hoses and bleed-line hose. Tighten the hose clamps over the inlet outlet and bleed-line nipples.
Step 12. Push the heater wires up through the bottom of the control box. Strip the green ground wire. Connect a ring terminal to the ground wire. Connect the ground wire to the heater grounding lug.
Step 13. Strip the black and white heater wires and connect them to H1 and H2 on the heater relay board.
Step 14. Plug in the REGTHERM and LIMTHERM thermistors. Make sure they are perfectly lined up with the pins on the motherboard, otherwise the red POWER light or blue LOGO light will start flashing and your spa will be inoperable.
Step 15. Plug in the pressure switch bypass jumper on the P34 Pressure Switch port ( J8 on the Eagle Box). If the pressure switch bypass jumper is not installed, the power and ready lights or the logo lights will start flashing and your heater will be inoperable.
Step 16. Connect the copper bonding wire to the bonding terminal in the IQ 2020 control box.
You’re all done! Good job!
