May 11, 2018 by OutsideModern

Blocked Filter

Lay Z Spa Type VI Filter
Type VI Filter for Lay Z Spas

Over time, body oils and other residue may cause blockages to occur in the filter. Usually, when a blockage occurs you’ll see an error code on the display that may read something like FLO.

This indicates that water is unable to get through the dirty filter and more often than not, your hot tub will stop working. The other issue you will have is that when a filter becomes blocked it’s no longer removing dirty contaminants.


To avoid your hot tub filter becoming blocked, be sure to clean it on a regular basis and replace when necessary. Not only will this help to maintain the health of your hot tub, but it will also help reduce your exposure to dirty contaminants.

If cleaning it doesn’t work and you’re still experiencing problems then it may be time to replace the filter. Most hot tub filters are pretty easy to change, but before you go diving in, it’s always best to check the instruction manual before you do to avoid any further costs.

There are a variety of different filter sizes and for different brands. If you have an Intex inflatable tub, check out our information on Intex filters here.

As a general rule of thumb, most hot tub filters should be changed approximately every two years.

Water Chemistry Imbalance

Water Test Kit Fix Your Hot Tub Problems
4-in-1 Test Kit

This is the number one issue that most hot tub owners experience at some point in their lives. But thankfully, it’s also one of the easiest issues to fix. By ensuring you have a healthy supply of water in your hot tub, you are helping to prevent future damage to your hot tub cover and filter. It’s a good idea to test the water in your hot tub regularly using 4 in 1 test strips like the Smart Test shown here. And physically check for any signs of mold, algae, or bacteria too.

If your water has a green tinge to it, this will most likely be caused by one of three things: low pH levels, algae, or low sanitizer levels. If you do find that your pH levels are too low, it means the water is very acidic.

Over time, if left untreated, this can cause the hot tub components to corrode. Algae is often quite easy to detect as usually presents itself as a slimy, green coating on the inside of the hot tub.

However, please note that algae can also come in other colors such as black or mustard, so don’t be alarmed if you see this growing too! Low sanitizer levels can also cause water to turn green and cloudy.


Spa Up
Spa Up

If the problem is low pH levels then this simply needs adjusting. To do this, first test the water for its pH and Total Alkalinity (TA) levels. You should always start by adjusting the TA level first as this helps to regulate the pH.

If the TA level is normal but the pH level is low then use a pH increaser like Leisure Time’s Spa Up to rise to the appropriate level; if it’s too high, you’ll need something like Leisure Time’s Spa Down.

When algae are the issue, they simply needs to be removed. Removing minor algae can be done using a treatment such as Leisure Time’s Spa Algaecide to wipe it any visible algae growth. If the algae growth is quite heavy you’ll need to carry out a more extensive treatment.

To do this, you should first use a system flush product to eliminate any algae that may be hiding in the plumbing. After the flush, you’ll need to drain the hot tub and wipe the inside clean with a non-foaming cleanser such as CleanAll. You should also take this opportunity to perform a deep clean on your filter or replace it if necessary.

Finally, refill the hot tub, then test and adjust the water’s pH and TA levels needed.

If the green water’s not being caused by low pH levels and it’s not being caused by algae, then it’s most likely that the sanitizer levels are low. To fix this simply test the levels first, use a sanitizer like Leisure Time’s Spa Shock and then adjust as necessary. You should always leave it around 24 hours first before retesting to allow the water time to adjust.

Heater failure

This is one of the most annoying problems you can encounter when all you want to do is sit and relax in a nice, warm hot tub. More often than not, heater failures are caused by corrosion of the heating element. A low ph (under 7.0) of water can cause this. If the heating element is exposed to low ph water for an extended period of time it will eventually damage the heating element and trip the GFCI breaker in the process.

Another issue it could be is a problem with the flow where not enough water is able to pass through the heater.

If however, your hot tub is full, it could be an airlock in the system that’s causing the heater to stop working.


If it is the actual heating element that’s failed you will need a hot tub specialist to replace this hot tub problem. If you find that it’s a problem with the water flow or circulation you may be able to fix this yourself.

First, check the water level and top up if needed. When this is too low, it can cause the heater to cut out, as not enough water will be moving through it.

If the water level is fine, and the problem appears to be an airlock, this is an easy fix. Simply open up the jets by turning them clockwise. Then disconnect the heater.

Next, you need to switch on the jets and let them run for 10-15 seconds to release any water inside.

Repeat this process until you get air bubbles emerging from the jets.

Burnt-out circuit board

Circuit board malfunction can be very costly to repair. The best way to prevent this from happening is through routine maintenance. Little things like heater terminal connection screws coming loose over time are enough to weaken the connection with the heater, causing damage to the circuit board as a result.

Physical signs of component damage include cracks, burn marks, or melting, though most systems these days will display some kind of error code if there are any issues with the circuit board.


Unfortunately, when it comes to burnt-out circuit boards, there’s not much you can do other than replace them. While this is a job you can do yourself it’s very important that you don’t get the wrong replacement.

Always refer to the installation guide before attempting to replace the circuit board. And most likely you’ll need to seek professional help.

Tripped GFCI/RCD breakers

To protect your hot tub from dangerous electrical faults which could lead to electrocution, a ground fault circuit interrupter (GFCI) or a residual current device (RCD) is fitted. These are designed to shut off whenever they detect an electrical current flowing somewhere unsafe.

The only problem with these devices is that they’re incredibly sensitive and even the lowest of electrical currents can result in the breaker tripping if any minor issue is detected.


Try and reset the GFCI first to see if that solves the issue. To do this simply press the reset button, and wait for the click. This should restore electricity to your hot tub. It should turn on and stay on.

If it does not, it’s time to call in an electrician.

Poor Circulation

The better the water circulation is in your hot tub, the cleaner it will be. If you don’t run the pumps long enough, you may get poor water circulation.

To ensure you get the best water flow, you should always run the pumps for around one hour for every 10 degrees of temperature.

Poor water chemistry can also cause issues. A ph imbalance can cause the pump seals to corrode and as a result, adversely affect circulation. To avoid a poorly circulating hot tub, make sure you check and clean the filters on a regular basis.

You should also make a habit of wiping away any dirt or grime around the walls of the hot tub to prevent the formation of biofilms.


In cases of poor circulation to solve the issue you need to first determine what’s causing it. If you’ve run the pumps for the recommended time above and you’re still having problems, here are a couple of quick fixes to try.

First, test the water chemistry of the hot tub. If this needs adjusting, do so and see if the problem subsides.

If it’s not the water chemistry causing poor circulation it could be that the water levels are too low, in which case top up the hot tub to see if that solves the issue.

It could be that your pump may have become clogged with debris, in which case simply clean the area and restart. Failing that, you should check the flow sensors or pressure switch are working correctly, which may involve the help of a specialist.

Leaky Seals

Whenever you experience water chemistry issues, as well as checking the water composition, it’s always worth checking the condition of the seals too. Rubber pump seals and o-rings wear over time. By replacing these on a regular basis you will help to preserve the life of your hot tub and avoid further, more costly, repairs later on.

If seals are defective, water leakage and buildup around the hot tub’s electrical equipment can cause it to short out.


If you do find your hot tub to have a leaky pump seal, you can attempt to repair it, but because they wear out so often and are relatively inexpensive, you may as well replace it for the best result.

To do this first you must loosen the bolts and remove the wet end. Once the wet end has been removed you can then replace the seal.

Always make sure you clean the inside of the seal plate before replacing the seal as this will help preserve its life.

Touching the seal with your hands can cause them to get scratched or damaged. So instead use the blunt end of a screwdriver or similar tool to replace it.

Water Pump Malfunction

Coleman LayZSpa Control Panel
Coleman LayZSpa Pump Control Panel

The first signs you’re most likely to encounter when there’s a water pump malfunction is a humming or hammering noise coming from the hot tub.

Broken seals, worn out bearings, and leaky water are also signs that there could be an issue with the pump. Again, with regular maintenance of your hot tub, this is an issue that can be avoided.

If not, it may be a case of replacing the pump, which is not particularly difficult to do but is still an unnecessary expense nonetheless.


If the pump is making a noise but not pumping any water it may be a case that there’s air trapped in the system somewhere, in which case you’ll need to bleed the air out.

To do this, first locate the drain plug on the pump and filter then open it up until the water starts to flow out. In the event there are no drain plugs, simply loosen the union of the pump. As soon as the water begins to drip, tighten it back up again.

If it’s not an airlock, it could be something blocking the hot tub’s drain. Always make sure drains are kept clear of debris and cleaned regularly.

If the pump is not making any sound or movement, it could be that the GFCI has tripped (in which case see the above section on tripped GFCI/RCD breakers). However, if that’s not the issue then be sure to check your clock to make sure it’s not stuck on a setting that’s overriding the switch you’re using. If it is, you’ll need to refer to the owners manual to see how to change this.