Leaks – Learn what to do when they spring up.

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This tub has sprung a leak, but where to start looking?

Hot tub owners will have to deal with a leak in their spa at some point. If you know what to look for, finding and fixing it can be a breeze.

If the leak is very slow, it’s well worth the money to try a pour-in Leak Sealant, which often permanently seals smaller leaks. If that product doesn’t do the trick, or the leak is larger, read on!

Finding the cause of the leak

After disconnecting the power, open the equipment compartment and look for obvious leaks or pooling. This is difficult if your spa has full-foam insulation, but the water-saturated foam is where to start digging until you find the leak source.

Another method is to let the water drop (with the spa off), observing the water level once it stops dropping. Investigate all jets or fittings just above the new water level for leaks.

The problem may be a Suction Assembly or another component within the tub if the water level drops all the way to the bottom.

Where do I start?

Leaks commonly stem from the following areas or components:

  • Pumps
  • Heater
  • PVC Connections & Unions
  • Valves
  • Jets & Manifolds


Pay close attention to the pump: is there water under it, or does the pump motor look like it’s been sprayed with water? If so, a pump seal failure could be the source of the leak.

Water spray on the motor and pump indicates a pump seal issue.

Seal KitWet End Assembly, or Complete Pump Assembly is called for if the pump seal has failed. In many cases, a new pump and motor assembly costs less than rebuilding the old pump and comes with a warranty.


There are 2 likely areas to leak on a heater: plumbing fittings on either end of the heater, or sensors/pressure switches.

Leak repair on a heater is as simple as replacing the Union GasketsPressure Switch, or the Entire Heater Assembly.  It’s best to replace the entire heater if it looks corroded or pitted to avoid headaches in the future.

PVC Connections & Unions

Unions (like the ones on the pump and heater) and glued fittings should be inspected as they’re prone to loosening with vibration and expansion/contraction due to heating and cooling. Hand tightening leaking unions will usually solve the problem. Never use tools to tighten hot tub fittings since they’re plastic and will break.

When hand tightening the union doesn’t solve the problem, replacement of the gaskets or O-Rings within, or replacement of the union as a whole, will.

Glued connections are tougher, but try these solutions before cutting the affected plumbing out and replacing it:

  • SpaBond Leak Seal Patch Kit permanently repairs cracks in hard surfaces like PVC or spa shells, and is as simple to install as a sticker!
  • Plast-Aid Acrylic and PVC Repair Kit is a 2 part epoxy kit that forms a permanent molecular bond to acrylic, PVC, polycarbonate, and ABS.
  • Seal-a-Leak Pour in Leak Sealer is a pour in liquid that seals minor plumbing leaks – great to try if you can’t find the source of a leak. Note: Pour in leak sealers will not cure leaking pump seals.
  • PVC Clip-On Pipe Repair snaps onto existing pipes, couplings, elbows, or tees, permanently sealing leaks at joints.

When the source of your plumbing leak just isn’t a candidate for the above 4 items, cut out the affected area and replace the necessary Fittings.


Hot tubs use 3 basic valve types: Shutoff ValvesDiverter Valves, and Air Control Valves. Shutoff valves and diverter valves are more likely to leak, as they actually control water flow.

Leaking shut-off valves are tricky and usually require replacement. Since these valves can be problematic, and serve no other function than to stop water flow so the equipment can be serviced, they’re often replaced with just a straight section of PVC.

The usual cause for Diverter Valve leaks is worn out or dry O-Rings within them. A simple preventative measure to keep the valve operating properly is to lubricate all the O-Rings and moving surfaces within the valve with Lube-Tube Lubricant yearly. Try reconditioning O-Rings with LubeTube or replacing them before replacing a leaking valve assembly.

Jets & Manifolds

Often what’s assumed to be a shell leak is in reality a jet leak. Jets have a flexible gasket that tightens against the spa shell, creating a seal. Over time, these gaskets can shrink or deteriorate, causing a leak.

Repairing jet leaks requires the removal of the jet housing from the spa and replacing the gasket. The sealing surface must be clean and smooth before installing a new gasket. Using Boss 802 Silicone Sealant on both sides of the gasket before tightening the jet ensures a positive seal.

This cracked jet manifold is the result of freezing water within the pipes.

Jet Manifolds are usually damaged when the water in the plumbing is allowed to freeze. SpaBond or Plast-Aid is your go-to solution if the crack isn’t severe, but replacement is required if the manifold is beyond repair.

Shell Cracks

The spa shell itself would rarely leak, but it’s possible. Blisters or surface cracks in the acrylic layer of the shell are usually cosmetic and aren’t the source of leaks.

To repair a surface crack, drill a very small hole (1/16” or less) on either end of the crack to keep it from spreading, thoroughly clean the surface around the crack, and apply either a SpaBond patch or, for larger cracks, Plast-Aid.

Still have questions? Leave a comment below.  Additionally, SpaDepot technicians are only an E-Mail or phone call away if you need help! Happy Hot Tubbing!

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