How to Install a Spa Heater

What You'll Need
Pipe wrench
Crescent wrench
Pipe thread sealer
Voltage meter

Installing a spa heater is a relatively simple task for someone with moderate experience. Just how simple it will be depends on which type of a spa you'll be heating, and which type of heater you'll be installing. The electric heater is the type most commonly used in portable, above-ground spas, while gas heaters are more often used with in-ground spas. The following will provide you with a guide to install your spa heater.

Step 1-  Choosing A Place For Your Heater

The best place to place your heater, gas or electric, is on the side of the spa pump that discharges heated water back into the spa.

Step 2- Positioning A Gas Heater

The best place to put your heater will be near the spa's pump and filter as close as possible to your gas supply. This will likely be a propane tank or a natural gas pipe.

Step 3-  Installing Your Heater

Once you've settled on a heater location, install the heating unit by connecting the PVC inlet water pipe to the heater's inlet opening with pipe couplers and unions. You will need to use pipe adhesive on the couplers. When connecting pipe to the heater, you should use a union that has pipe threads so that in the future, you can disconnect the water pipe from the heater if it becomes necessary. You'll also need a pipe wrench to tighten the union.

Step 4-  Connecting The Heater's Power

Connect the electrical wires coming out of the heater's control box to a male AC plug, or connect them directly to electrical outlet wires. Make sure you turn off the power before touching the live wires.

Step 5-  Connecting Your Heater To Your Gas Supply or Electrical Power Supply

To connect your gas supply, use a copper or flex pipe with a shut-off valve. Connect the pipe to the gas fitting on the heater. Be sure to use thread sealer on all pipe connections and tighten each connection with a wrench to ensure that gas will not leak at this fitting. Test each fitting for possible leaks by spraying it with soapy water. If there are leaks, you'll see bubbles appear at the fitting.

Installing an electrical heater is similar. First connect the PVC water pipes, then the power connections.

When all connections have been made, restore power to the heater and test it out. If the water flowing into your spa is warm, that means you did it right.