Often when a heater stops working, it’s the element that has failed.
Replacing the element can be a tricky repair and not always possible with certain models of heaters. Most Low flow heaters must be replaced entirely when they fail, as elements are not available. Many different high flow heater elements can be replaced. In this section we will focus on the most common. Keep reading for a step-by-step instruction on how to remove and replace a standard High Flow heating Element.
**This procedure is only recommended for heaters that have nut and bolt connections at the heating element. If you have soldered on wires connected at the heating element that connect to the circuit board, you must replace the entire heater. Element only replacement is not recommended. **
Step 1
Turn Power off at the circuit breaker that powers the spa.
Step 2
Close valves to isolate the heater, if no valves are present, you must drain the spa.
Step 3
Inspect the heater canister closely. Look for corrosion, pitting, rust, discoloration, warping, and any other types of damage.
Step 4
If any of the above damage is found, you should replace the entire heating assembly.
Step 5
Unthread the unions that connect the heater to the plumbing. Be careful, as water that is inside the heater and plumbing lines will drain out at this time. Be sure no tools, supplies, or anything else sensitive is in the path of the draining water.
Step 6
Inspect the gaskets that seal the heater to the plumbing. Discard if they show signs of flattening, discoloration, become “gooey”, or are stuck to the plumbing fittings, and need to be peeled off. Gaskets are extremely inexpensive and should almost always be replaced when performing repairs.
Step 7
Once the unions are open and the water is drained out of the heater, proceed to removing the electrical connections that connect the element to the circuit board. This step is often where mistakes are made, and damage is done.
Step 8
When removing the electrical connections from the element be sure to always remove at the element and not at the circuit board.
Step 9
The Element “Posts” that protrude up and out of the heater canister usually have a 3/8” Hex Nut that secures the electrical wire or copper strap to the element. This must be loosened and removed.
Step 10
Most element manufacturers will include a wrench connection below the threaded part of the post. This is meant to steady and hold in place the element post, so it doesn’t spin and break the epoxy seal that prevents the water in the heater from coming up and touching live electricity.
Step 11
Locate this hex area under the threading of the post. The size will usually be either 3/8” or ¼”.
Step 12
Here you will be using two wrenches at once. With a wrench firmly on the lower hex, use another 3/8” wrench and loosen the 3/8” nut on top of the post. Be sure the post does not spin or move. Once the nut is loose, remove by hand and set aside.
Step 13
Repeat the procedure for the other element post.
Step 14
Once the electrical connections are removed and wires or copper straps are moved out of the way, proceed to the ¾” Nut that secures the element to the canister.
Step 15
Using a ¾” wrench, loosen the nut and remove. If the nut is seized and unable to be loosened easily, attempt to tighten slightly first, then again attempt to loosen. If the nut will simply not come loose, consider replacing the entire heating assembly.
Step 16
Once the ¾” nuts are removed, the element should feel loose. With a screwdriver, push the element posts down into the canister and off to the side a bit so they don’t pop back up.
Step 17
At this point, the element is ready to be removed.
Step 18
If there are any sensors or anything protruding into the canister, you may need to remove it before pulling the element out.
Step 19
If the path is clear, pull the element out. Using a pick with a hook works great, if you don’t have one, use a pair of pliers or your fingers. Pull the entire element out of the canister and set aside to be either recycled or discarded.
Step 20
With the element out of the way, inspect the top of the canister where the ¾” nuts were previously. If you find a lot of corrosion, any pitting, or other damage, replace the entire heating assembly.
Step 21
If there is no actual damage, proceed to clean the area well with a shop rag.
Step 22
Open and prepare the new element for installation.
Step 23
Remove the ¾” nuts off the element if they are installed.
Step 24
Notice there are 2 black rubber o-rings that are located under where the ¾” nuts go.
Step 25
LIGHTLY lubricate the o-rings with a lubricant approved for pool and spa applications. Do not over lubricate the o-rings, as slippage can occur resulting in a leak.
Step 26
Once the element is ready to install, insert into the canister. Be sure to insert so the electrodes are on a slight angle.
Step 27
Push element into desired location look at the top through the holes. Once in the area, turn the element so the electrodes pop through the holes.
Step 28
Proceed to install the two ¾” nuts and secure the element to the canister. Tighten firmly but do not over tighten.
Step 29
Look inside the heater canister from the side. Be sure the element is not touching the inside of the canister in any way. The element must be mounted so no parts are touching the sides.
Step 30
Re-install the copper straps or wires to the element posts. Be sure to hold the lower hex of the post at the same time when tightening the 3/8” hex nut on top. Failure to properly hold the post in place when tightening will result in the post moving and breaking the epoxy seal. This will cause a leak and most likely trip the breaker. If this occurs, the entire job will need to be repeated with a new element.
Step 31
At this point, the element should be secured to the canister, attached to the electrical wiring or copper straps, and checked for proper position inside the canister.
Step 32
Lightly lubricate the new union gaskets and install in the tail pieces of the heater plumbing.
Step 33
Screw on the union nut, do not overtighten as the union nut will crack.
Step 34
Open valves or fill the spa. If filling the spa, place hose into the skimmer so the plumbing is filled as the tub fills. Doing this will help prevent an air lock situation. It will also allow you to catch a leak at either of the unions or the element quickly.
Step 35
If no leaks are found and the tub is full, proceed to normal startup operations.
Step 36
If you want to check the element for proper operation, you can follow the above instructions on diagnosing a bad element. Test for power going to the element, and amperage being drawn on he circuit. Remember the circuit is live and electricity can be dangerous. If you are not comfortable, and not used to testing and dealing with live electricity, simply let the spa work and heat itself. You will notice a small heat rise within an hour or less generally. Check to make sure the spa eventually reaches its set temperature.
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