Hot tub jets not working: causes and fixes

When hot tub jets are not working, the cause is usually simple: an air lock after a refill, jets or a diverter valve turned closed, a dirty filter, or low water. Check those first. If the pump is silent or only hums, the problem is the pump or its power, not the jets.

Match the symptom to the cause

Symptom	Most likely cause	Fix
No jets, pump runs, just refilled	Air lock	Bleed the air
All jets weak	Dirty filter, low water, clogged impeller	Clean filter, top up
Some seats work, others do not	Diverter valve position	Turn the diverter
One or two jets dead	Jet turned off, clogged, or broken insert	Open, clean, or replace the jet
Jets surge or sputter	Pump drawing air: low water or blocked filter	Top up, clean filter
Flow but no "punch"	Air controls closed	Open the air valves
Pump hums, no flow	Seized pump, bad capacitor, or jammed impeller	See the pump guide
Nothing happens, no sound	No power to pump, panel or board fault	Check breaker and display
Only low speed works	Pump motor or board relay	Technician

Step-by-step checks

1. Check the water level. It must be above the highest jets and about halfway up the skimmer opening. Low water lets the pump suck air.
2. Open the jets. Most jet faces rotate to adjust flow. Turn each one counterclockwise to open. A closed jet looks exactly like a broken one.
3. Turn the diverter valves. The large knobs on the top edge of the tub send water between seating zones. Turn each slowly from one end to the other with the pump running and see which jets respond.
4. Open the air controls. The smaller knobs add air to the water stream. With them closed, jets feel soft.
5. Clean the filter. Turn off power at the breaker, remove the filter, and rinse it. To test, briefly run the pump with the filter out. If the jets come back strong, the filter needs a deep clean or replacement. See how to clean a hot tub filter.
6. Bleed an air lock. With all jets open, run the pump on low for 10 to 15 seconds, then high for 10 to 15 seconds, and repeat a few times. If that fails, bleed air at the pump union with the power off. Full method in startup after draining.
7. Check the display. A flow or heater code confirms a circulation problem. Run it through the AskTub code decoder.
8. Listen at the equipment bay. Running normally, humming, grinding, or silent each point somewhere different. See hot tub pump humming or not working.

Fixing individual jets

Remove and clean

Most jet inserts come out from the front. Turn the jet face counterclockwise past the closed position until it clicks or stops, then keep turning or pull. Some styles unscrew, others unclip. Check your owner's manual if it resists. Do not force it.

1. Turn off the pumps.
2. Remove the insert.
3. Rinse out grit, hair, and scale. Soak a crusty insert in a 50/50 mix of white vinegar and water for a few hours, then rinse.
4. Look inside the jet body in the shell for debris.
5. Reinstall and turn clockwise until it seats.

Replace

Replace the insert if the face is cracked, the spinner no longer spins, the bearing rattles, or it will not stay in. Jet inserts are brand and size specific. Before ordering:

• Measure the face diameter.
• Note the style: directional, rotating, pulsating, or cluster.
• Look for a maker's name or part number on the back of the insert.
• Note whether it threads in or snaps in.

Browse hot tub jets with the old insert in hand.

Diverter valves

A diverter that is stiff, will not turn fully, or lets water through to both sides when it should not has worn internals or grit in it. With the power off, the cap usually unscrews by hand and the internal piece lifts out. Clean it, replace the o-rings, lubricate with a silicone lubricant made for spa o-rings, and reassemble. Never force a stuck handle. The stem snaps.

Weak jets on an older tub

• Clogged impeller. Debris that got past a damaged filter lodges in the impeller vanes. Flow drops even though the motor sounds fine. Clearing it means opening the wet end.
• Worn impeller or wet end. Years of running wear the clearances. A new wet end restores flow without replacing the motor.
• Scale in the plumbing. Hard water narrows the lines and jams jets. Keep calcium at 150–250 ppm.
• Suction leak. A loose union or cracked fitting on the suction side lets the pump draw air. Look for bubbles from the jets with the air controls closed.
• Partly closed slice valve. If the tub was serviced recently, check that the gate valves beside the pump are fully open.

Two-speed pumps and timeouts

Some things that look like faults are not:

• Jets shut off automatically after 15 to 30 minutes. Press the button again.
• On low speed, a two-speed pump only gives a gentle flow. That is the filtration speed.
• A small circulation pump runs silently around the clock and does not power the jets at all.
• During priming mode after power-up, the tub waits several minutes before normal operation.

When to call a pro

Call a technician if the pump hums and will not start, trips the breaker, runs on one speed only, or leaks at the shaft, or if a jet body behind the shell is cracked. To match a replacement, see which hot tub pump do I have.