Hurlcon Spa Heater – How To Replace HX Manifold


Are you having problems with your Hurlcon spa heater? Is the in/outlet manifold leaking? There’s a good chance your heater in/outlet manifold may need replacing.Over time the water balance may have affected the heater manifold and some of the internal parts may have damaged beyond repair. Heres some simple instructions on how to replace a Hurlcon HX spa heater manifold. If you have a Hurlcon WX spa heater, this is the same as a HX model heater. The only difference is how the water pipes are plumbed into the heater. The HX heater is plumbed with 40mm PVC where the WX heater is plumbed with flexible hosing.

When a Hurlcon HX spa heater manifold needs replacement these are the parts you will need to order.

  1.  Hurlcon HX Manifold Complete
  2. Hurlcon HX heat exchanger adapters x 2
  3. Hurlcon HX adapter orings x 2
  4.  Hurlcon HX split pins x 4
  5. Hurlcon HX hi-limit 55deg sensor x 1

You can order the kit here – Hurlcon Spa Heater HX Manifold

Below is a step by step instruction on how to replace a Hurlcon spa Heater HX manifold. All care and caution should be taken when conduction this repair. If you are not confident with carrying out this procedure contact a your nearest licensed heater service person.

Step 1 – Removing the Existing HX Manifold & Wiring

The first step is to remove the old manifold. In order to do this you will need to remove the top and bottom heater panels and you may even need to remove the the left and right heater uprights. Once part of the metal cabinet has been removed you will need to remove the pressure switch and hi limit wiring along with the sensor lead that may be silicone into the inlet manifold side.

Then proceed to the manifold itself. You will see as your looking at where the manifold joins to the copper heat exchanger. See the to split pins, 2 on the left and 2 on the right. You need to remove both of them. Once that is done the manifold will drop to the floor. Now you can see the two heat exchanger adaptors that are screwed onto the heat exchanger. Turn these anti clock wise to remove them from heat exchanger. once these have been removed you should see the same as this image below.


Step 2 – Installing the Heat Exchanger Adapters


Now the second step to replacing the manifold is to install the new heat exchanger adaptors. Firstly use something like Plumb-tech sealant and put these around the threads of the heat exchanger then screw on your new adapter. You can see from the image that it will nearly screw up to the very top.

Next place your adapter oring onto the bottom section of the adapter. The top grove you see there is for the split pins and not the oring. Once both orings have been installed use some sealant grease like Vaseline and place it all over the oring. this is a crucial factor when replacing this manifold, failure to do so will mean you wont be able to push the manifold up onto the adapters correctly.

Your two adapters should look like this.


Step 3 – Installing the Hurlcon HX Manifold


Now get your split pins ready. With one hand push and hold up the manifold. You will need to hold up one side at a time and with the other hand push each split pin into the manifold and use some pliers to grab the end and push right through till you see the pin come through the other side. Be careful here as you should not have to really force that pin through. If you have the manifold held right up to the adapter as i have it in the image below your split pins should be easily installed. Once you have bother sets of split pins installed then been over the open ends of the pins. This will stop them from vibrating out.

Step 4 – Checking Your HX Manifold Installation

So now you have your Hurlcon HX manifold installed. Now you are ready to re install the heater paneling and replace the wire connections.


Step 5 – Reconnecting the Heater Sensors and Wiring to the HX Manifold

You will need to reconnect your thermostat sensor lead into the brass sensor pocket. You can reconnect the hi-limit wiring as well as the pressure switch wiring. Reconnect your PVC pipework and then its time to fire up the heater and check there are no leaks.


Hurlcon Spa Heater Manifold Checks

Now that your manifold is installed and tested and you have no leaks you will now need to test the pressure switch to make sure it shuts down correctly as it may need some adjustment. Testing your pressure switch is quite simple. First turn the pump on and turn the heater thermostat display to the off position. Now that the spa pump is running you should see a little upside down “Q” symbol on the display. This indicates that there is enough water pressure to activate the heater and start the ignition process. Now turn the pump off and look at the display again. The “Q” symbol should disappear with in a could of seconds. That means the pressure switch senses that there is no water flow and the heater shuts down. This is how the Hurlcon spa heater is suppose to operate. Try this a couple of times to make sure that the heater shuts down correctly. If it does now try it again with the heater turned on and run the pump with the heater on for at least 25 seconds. Same thing turn the spa pump off and see if the heater turns off, it should if it does not then some minor adjustment on the pressure switch will be needed and then testing operation will need to be performed again.

Here is the instructions that Astralpool Hurlcon provide to pressure switch adjustment. If this is something you cannot do then you will need to have a licensed gas fitter/service agent to attend your property to fix.

Pressure Switch Adjustment

hurlcon spa heater-pressure-switch

Download the Hurlcon HX Heater Manual Here