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Things That You Should Not Modify On Your Pool

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pool repairs you should hire an expert for

After many years of swimming pool ownership it is easy to develop a familiarity, and complacency, when it comes to the pool and the individual components that make it up. Despite how safe swimming pools can be there also exists the potential for hidden dangers - especially if you attempt to change or modify your pool on your own. In addition to the potential to cause a safety hazard there also exists the possibility that you will inadvertently cause damage to the pool itself. Sometime this damage can be catastrophic and even cause a total failure of the pool.

All too often pool owners attempt to interact with their pool or equipment in order to conduct a repair but without the benefit of years of trade experience working on pools they risk causing a much bigger problem. This article is a warning to pool owners that serves to identify some parts of your pool which you should never attempt to modify on your own.

This list is NOT inclusive of every potentially dangerous item or area of your pool. This list is based on some of the more common components that pool owners tend to interact with but should not be considered as an all inclusive safety guide for pool or spa ownership.

You should also note that you should definitely not be "afraid" of your pool. It is important however to become informed about the potential concerns to make your swimming pool or hot tub as safe as it can possibly be. Negligence and ignorance are the greater concern and educating yourself as to how your pool works is critical in being able to determine when it is safe to perform a diagnostic or repair yourself - and when you should pay to bring in an industry professional.

Pool Bonding & Grounding Systems

no bonding wire on bonding lug
Near to the top of the list for things that the average pool owner should not attempt to modify is the bonding and or grounding protection on your pool. Swimming pools require both bonding grids as well as grounding in order to operate safely. Without a properly designed bonding grid and ground the pool can experience unusually fast rates of deterioration and corrosion - but more importantly the safety of the swimmers is at risk.

A bonding grid is designed to connect every metal component in and around the pool to the same electrical potential. The bonding grid is then grounded to make that electrical potential equal to zero.

Lack of bonding - A lack of bonding to any metal component in or around the pool creates the concern of having two different electrical potentials within contact of the water or the swimmers. If a swimmer were in the water they are isolated and at the same electrical potential of the pool. If they were to reach out and grab something that was not bonded to the rest of the pool systems, and had a different electrical potential, then the swimmer becomes a "shunt" in between two differing electrical potentials. The electricity will seek to balance itself between the two sources and the swimmer is the conductor that permits this exchange of electrons. A very dangerous situation indeed. Mild currents or low voltage differences would be felt as a tingle or mild shock. If you EVER experience this in or around the pool the pool must be closed immediately until the bonding and grounding systems can be checked and verified by a qualified electrician specifically familiar with swimming pool bonding and grounding.

incorrect method of grounding a pool
Lack of grounding - A lack of grounding has a different concern, though similar, to what a lack of bonding introduces. With a bonding grid in place all metal components in and around the pool and pool equipment are forced to the same electrical potential. Without the bonding grid grounded properly then the electrical potential of all metal components in your pool will be the same...which could be zero volts or it could be 120 volts. Grounding the bonding grid is what forces the metal components in your pool to be equal to the lowest possible electrical potential. Zero, theoretically.

A very common mistake made by pool owners and under-educated pool service technicians is to modify or add to the bonding grid or grounding point. A very common situation is where a piece of equipment is added and instead of adding to the existing bonding grid, a new grounding rod or grounding plate are buried in the ground and connected to the equipment. This shows a fundamental lack of understanding of electrical theory and would actually serve to cause a problem - not fix one.

The ground connection of the house main electrical panel is not necessarily the exact same electrical potential as a grounding rod buried in the ground in the backyard. In theory they should be the same, but in reality there can be minute voltage variances and this would cause a constant current trickle within the pool passing between ground points. Even many legitimate electricians do not fully understand swimming pool bonding and grounding and the differences between them. If you are attempting to add new equipment or interact with the bonding or grounding system for your pool then this would be an optimal time to call in a professional that has experience in these matters.

Suction Points & Main Drain Covers

old pool pump entrapment warning tag
A very common potential danger in swimming pools, perhaps one of the most common dangers, relates to the potential for an entrapment hazard from an under water suction point. After you have been swimming in your pool 1000 times it is only normal that you would start to take potential dangers like entrapment hazards for granted. The reality is that there was a major change to the pool and spa industry that came into effect late in 2008. The Virginia Graeme Baker act is a law that relates to suction and entrapment hazards due to the unfortunate death of the granddaughter of former Secretary of State James Baker III. While this was not an isolated death, and entrapment hazards in pools and spas cause deaths yearly in the USA, it was this specific incident which fast tracked the VGBA law as it exists today.

While the VGB act is primarily targeted towards commercial swimming pools, residential pool owners would be wise to not make assumptions about how safe (or not safe) their backyard pool is. All suction point covers should be upgraded to VGB compliant covers and there are many residential pools which have not done this yet. Given the mostly non-serviceable location of the main drain on the bottom of the deep end of your pool it can be obviously difficult to inspect or upgrade your drain covers. Given the importance of this safety concern it would be well worth the investment to hire a pool professional or pool diver to inspect your drain covers and upgrade them as needed. All too often residential pools have failing, out dated, broken or missing main drain covers. This is not something that you should ignore in your pool and not something that you should attempt to modify or replace on your own. All too often pool epoxy is used to fix small problems on older equipment like a failing main drain cover. You should not attempt to modify or repair an old main drain cover under any circumstances. You should also never remove a main drain cover and operate your pool without one.

Part of the problem with suction points in swimming pools is that there are multiple different orientations that your plumbing system might be installed in. Some main drains for example are not under direct suction but instead used only as an equalizer line (non pressure line) connecting to the skimmer. Do you know if your main drain has direct suction or is it an equalizer line only? Some pool plumbing systems have independent pipes that run from each component of the pool directly to the equipment pad. If this is the case with your pool then you will have a suction manifold where multiple pipes will converge directly in front of your pump. Most often these will have isolation valves installed to control flow in each line. If you were to close every valve except for your main drain suction then you have effectively created a potential suction hazard. Now, blocking of the main drain (drains) would result in becoming trapped due to the suction of the pump having no other outlet to draw through. This is the concern with taking the approach of just turning valves and hoping for the best if you do not know how to interact with your equipment correctly. It would be well worth the investment to hire a professional to inspect your pool installation and provide you with a written report and pool school specific to your system and how you should interact with it.

An additional consideration for VGB compliant drain covers and entrapment hazards has to do with suction flow rates. In fact, other than the physical shape of the drain cover itself, the designed flow rates are the most important consideration that dictates the safety of a drain cover. If you are a pool owner with a 1.5 horsepower Hayward Super Pump and you decide to upgrade to the 2.7 horsepower EcoStar - did you just increase the flow rate of your suction lines beyond the safe threshold for VGB compliant drain covers? Possibly. In order to answer this question you would need to know the maximum designed flow rate for your specific drain covers (usually embossed directly on them) as well as the flow rate of your system. This is an advanced calculation which you can short cut yourself if you were to order and install a flow meter so you can easily determine the flow rates of your system.

Suction flow and pressure side flow are different on pool systems so in theory you would need to have this flow meter installed on the suction side plumbing in order to determine accurate suction line flow rates. Given the importance of operating your pool within the standards established by the ASME/ANSI and the VGB act specifically you should consider consulting with a pool and spa expert when considering to upgrade your pump. It is possible that your pump was not sized correctly to your system when it was installed initially and upgrading to a larger pump may be a bad idea altogether. Add into this any uncertainty about flow rates, plumbing configurations and out of date drain covers and you can easily see how investing in an industry professional may be well worth it to make sure your pool is safe.

I could not mention the subject of entrapment hazards without mentioning the need for dual suction points on any suction line in your pool. Many residential pools operate with single suction main drains which is something that you should not see from a modern day swimming pool installation. By separating the main drains into two suction points this dramatically reduces the potential for an entrapment hazard. If you have a single suction main drain in your pool you should have your system inspected to see if you have suction in that line or if the main drain is set up as an equalizer only.

Swimming Pool Filter Repairs

skull cracked from exploding pool filter
The picture to the right is an actual scan of a young man with a cracked skull after his pool filter exploded. You can read some questions and answers he was kind enough to provide on this reddit post he made about his accident. While rare, if you experience an event with an exploding filter while you are in the vicinity, you are very likely to be seriously injured or killed.

If you have a failure with your pool filter of any kind then you should not attempt to modify or repair your filter - at all. A filter tank is a pressure vessel and the thing about pressure vessels failing is that they tend to do so in an explosive fashion. Your pool filter can operate at up to 30 PSI under normal conditions and almost all pool equipment has a safety threshold of 50 PSI beyond which failure is expected. Would you want to be standing next to a three foot tall pressure vessel at or exceeding 30 to 50 PSI when it explosively fails? Certainly not. Fortunately exploding pool filters and the resulting injuries are rare...but still a possible area for concern.

While there have only been 22 reported incidents of serious injury from exploding pool filters since 1982, including four deaths, this is still an aspect of your pool that you need to respect. The major area of concern is with band clamp style filters that have a split filter tank. In cases where air becomes trapped within the filter elements, or from the band clamp not being installed correctly, it is possible for the top of the tank to explosively blow off. Fixing or modifying the band clamp on your pool filter is an absolute no-go and if you note any kind of deficiency with your filter tank or band clamp you should replace the deficient components or contact an industry professional to ensure your filter is installed and operating correctly.

While split tank filters are the primary area of concern the reality is that any pool filter can be dangerous. When you pressurize your system you can actually see (and feel) the filter tank swell...which is an offputting feeling. Seeing this in person will give you a little more appreciation for the power of a pressure vessel. Under normal conditions your filter tank feels completely hard, rigid and unmoving. Once you turn the pump on you can see the tank swell as much as 1/2" in size. The pressure created by a pool pump is nothing to scoff at and any deficiency in your filter should be fixed by replacement parts only. Never attempt to repair leaks or cracks in a filter tank with epoxy, silicone, JB weld or any other form of topical sealant as this could be dangerous plus the swelling of the tank will prevent any of these from fixing the problem anyway. If your filter tank is deficient enough to have failed once then it now has a compromised structural integrity and should not be pressurized. Replacement is the only solution for failing parts on your filter.

Pool Heater Troubleshooting

Technical support for pool heater fire
One of my least favorite emails to get from readers of this website is pool owners asking about troubleshooting steps for their natural gas or propane heater. When I worked for a major equipment manufacturer doing technical support I was prohibited from providing troubleshooting information for gas heaters unless the person I was speaking with could provide me with their valid gas fitters licence number. This policy, while self serving in terms of limiting the liability of the company, is actually a very smart idea. Pool owners in general have no appreciation for how powerful and dangerous a gas fired pool heater can be.

At 200,000 to 400,000 BTU's the average residential swimming pool heater is as powerful as as many as 10 large BBQ units. Think of how much heat a large BBQ belts out then multiply that by ten times. Under normal operating conditions this would not pose a problem as pool heaters have been designed and built with safety as a priority. Where you get into problems is when your heater is not functioning correctly or should you begin to troubleshoot the problem or modify any of the components.

I certainly understand the desire for pool owners to take steps on their own when things stop working correctly on their pool. If you called in a professional every time your pool had a hiccup this would surely be a fast track to the poor house. That being said a pool heater is just about the last piece of equipment you should attempt to troubleshoot or modify in any way. When I receive contact from a pool owner asking how to diagnose why their pool heater will not work I only refer them to speak with a licensed gas technician. There is just no safe way for a pool owner to diagnose and repair a malfunctioning heater other than to verify the heater has power, and that the gas valve is open. The only other thing you should try as a pool owner is to clean / backwash your filter and this will often resolve problems with your heater not firing. If it does not then you should call a licensed gas technician to inspect and diagnose the problem for you.

Red Green Pool Heater Repairs Regular maintenance for your heater is the secret to problem free longevity. If you own a pool heater it is recommended that you have it cleaned and inspected every spring. When you skip this regular service there will be a build up of debris and soot in most brands of heaters which will cause the fuel air mixture for your heater to change. This results in a less clean burn which will in turn cause more soot to accumulate. In my experience paying for a yearly spring cleaning and startup is well worth the investment to the average pool owner. If you are thinking about trying to monkey with your pool heater to get it to light then give your head a shake.

When I started in this industry many years ago it would be common place to see the front door blow off the heater when you tried to light it. Today there are far more restrictions on who is allowed to light a pool heater, and pool heaters in general have advanced in terms of electronic ignition systems as well as safety systems designed to prevent explosions due to improper lighting or heater malfunction. If you can not get your heater to light then this is the most likely reason why...there is a problem and your heater is trying to prevent a dangerous situation by not lighting. Never modify your pool heater and avoid doing diagnostic work inside of your heater unless you are specifically experienced with this.

Electrical Work Around Your Pool

safety last - dead last electrical work Electricity in general is something that you should not attempt to work on if you are not specifically experienced with established safe industry standards and working practices. All too often home owners attempt to do electrical work which they really should not be doing. When it comes to swimming pool systems this is even more important. Electricity is dangerous under optimal circumstances. When you start combining electrical systems along with thousands of gallons of water you need to be certain that you are doing the work correctly.

GFI circuit protection - Most home owners are familiar with the need to have ground fault circuit protection on any electrical system on or near water. A GFI provides a hair trigger for over current situations, or should current be detected somewhere where it should not be such as in the ground wire of a powered device due to a fault in the device. A GFI most specifically protects electrical systems that are in close contact to water and every aspect of your powered pool system should be protected with a GFI. If you are not familiar with the need for GFI protection, or how GFI systems work, this can lead to a potentially dangerous situation. You should never attempt to change or modify the electrical system for any component of your pool unless you are specifically familiar with electrical installations.

You can tell if a circuit has GFI protection if you are looking at a GFI outlet, or if you can identify a GFI reset switch on the breaker feeding the circuit. This is not always conclusive as to if a power source is GFI protected. An example of this would be the outside plugs on your home. Most likely if you go take a look around your home you will see that most of the plugs are not GFI receptacles...does that mean you should change them to GFI plugs? No, most likely not. GFI plugs have both a line side connection as well as a load side connection. If you connect power to the "line" side of a GFI then anything that you plug into that receptacle will be protected. Instead of every plug being a GFI the most common installation would have the first plug on the circuit be a GFI receptacle where all plugs further down the line are not GFI plugs. If the additional plugs are wired on the "load" side of the initial GFI then all concurrent plugs are protected by the oginial GFI. Where this becomes a problem is that you can not have two GFI's on one circuit. If you accidentally connect a new GFI plug onto a line that is already GFI protected then you can experience intermittent problems or potentially a lack of GFI protection.

Another concern is the use of code compliant wires and wire connectors on pool systems (2:40 of this video). I would go so far as to say that most residential pool equipment is not wired correctly, or at least not with the correct water proof wires and box connectors. A regular L-16 connector for an electrical box (inside the home) is well less than a dollar for even the good ones. An electrical wet connect could be $25 for the same thing...except the water proof version. The same goes for the choice of wire. Loomex (or Romex) the standard for interior residential wiring is not suitable for use outdoors and yet you see this all the time in the field. Even the shielded BX cable is not the right choice for a wire that will be exposed to the elements - especially water.

Tech cable is a great choice for pool equipment installation but it is well more than 10x the price of regular Romex or BX cable. Outdoor rated PVC conduit and boxes are another good option, but again you would need to know that you need to spend extra on these items. The average pool owner may look at what they have now and install new equipment using similar materials. It is possible, probable even, that your original installation was not done correctly or perhaps was allowable under a "grandfather clause" for older equipment. Once you begin to make changes, or upgrades, you may be required to bring the electrical installation for your equipment up to current code. Any attempt to make changes to or add to your current swimming pool electrical system should be completed, or at the very least inspected, by a qualified and licensed electrician.

Don't Be Afraid - Be Informed

More than anything the greatest concern for potential danger with your pool is from a result of someone working on something that they do not have a complete understanding of. If you do not know how to vacuum your pool but you want to learn - then have at it! There is very little that can really go wrong from you attempting to save some money by working on your pool yourself. You do however want to be sure that you limit the work you do to safe and productive things and leave the more dangerous and technically difficult modifications and repairs to the experts.

In terms of the health and well being of the pool itself, as well as the equipment, you certainly would not want to cause a problem due to your inexperience. If you do then you will learn the hard lesson of having to pay for something you broke. In the world of pool ownership by far the worst and most poignant of these lessons would be as a result of improperly draining your pool. Draining a vinyl liner pool below six inches of water left in the shallow end will (more times than not) result in you needing a new liner. Like immediately. Draining a concrete pool or a fiberglass pool is even less forgiving as the hydrostatic pressure of the ground water surrounding your pool can actually lift your pool out of the ground - permanently breaking it. This is a lesson that no pool owner wants to experience first hand I assure you.

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