Replacing a Flow Switch Tee 2000 – 2009

On Dimension One Spas with a low-flow heater, the black flow switch replacement barb is no longer available. If the flow switch tee cracks it must be repaired or replaced. This instruction sheet shows how to replace the tee and use the existing barb. Our first recommendation is to replace the complete heater assembly because it includes a new flow switch assembly and will save time and aggravation. However, if you are patient and want to save the cost of a new heater, dive right in.

Some of the tools required:

Turn off the power at the GFCI for 1 minute, and then turn it back on. If the message clears, it was likely a false error reading. Your spa should now return to its normal operation.

  • Dremel and good cutting wheel.
  • Locking needle nose pliers
  • 2-part Plastic Epoxy

Step 1

Drain the spa of water and remove the heater assembly. You’ll need to work on a bench so there is access to all sides of the tee.

Step 2

Remove the flow switch assembly and store for now. The “Flapper” portion of this assembly is fragile so be very careful handling and storing.

Step 3

Using a hack saw, cut the tee just to left of the neck. Be careful not to cut the end of the black barb we are trying to re-use.

Step 4

Using a Dremel and cutting wheel, cut slots in both directions to achieve a cross-hatch pattern. This photo shows the first set of cuts.

Step 5

Using a pair of locking needle-nosed pliers, begin peeling or breaking off pieces of the clear plastic tee. This is the most difficult part of the job because the small pieces of plastic don’t really want to come off. Here is where the patience comes in. I wore a thin glove to prevent the piers from snapping closed and pinching my fingers. (Sometimes the plastic comes off in 2 layers.)

Step 6

When the old tee is completely removed the remaining tee looks pretty beat up. (Left)

The rough surface won’t allow the new tee to slide completely into place. (Right)

Step 7

Using a Dremel grinding wheel, begin smoothing the barb. (Left)

Use sand paper or a sanding block to complete the process. (Right)

Step 8

If the new tee will slide onto the barb, you are ready to install it. Use the instructions on the Plastic Epoxy to install the new tee. When in place, the neck should tilt towards you about 30 degrees. This will allow for easy replacement of the flow switch later if necessary. Remove any excess epoxy that could reduce water flow through the new tee. Allow the epoxy to cure.

Step 10

Install the flow switch into the new tee. There is a trick to doing this correctly, so be sure you have our instruction sheet for this step.

Step 9

Re-install the heater assembly into the spa.

Step 11

Fill the spa with water and cross your fingers.