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Astralpool / Zodiac 55°C High-Limit Thermal Switch - Normally Open - Non-Standard

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$109.00 $140.00

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Astralpool / Zodiac 55°C High-Limit Thermal Switch - Normally Open - Non-Standard

Astralpool / Zodiac

Physically Stocked, unlike most "drop-shipping" websites.
Shipped from VIC, NSW, WA, QLD

This is a 55°C Normally-Open (NO) switch used in some older Hendy / Hurlcon boilers. These are uncommon, and do not confuse with the standard NC (Normally-Closed) style of these switches listed here.

Manufacturer Catalogues, Diagrams & Part Numbers

Need exploded views, spare part numbers, product numbers, diagrams, or more product information? See the manufacturer catalogues: Astralpool Catalogue 2026 | Zodiac Catalogue 2026

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55C Normally Open - Non Standard

Important Information

Delivery Pricing & Options

*Free Road Shipping on orders over $149.00 Australia-wide
Capped Road Freight Shipping at $19.95
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About Us

Heater & Spa Parts is built on decades of real pool and spa industry experience, from manufacturer R&D and consulting to in-field spa repairs, pool heater servicing, trade support and diagnostics.
We understand how the equipment works, why it fails, and why it should be replaced.
More Parts than Anyone

We are a real Australian store with real stock, not a drop shipper.
With 100,000+ parts across 10,000+ product lines, we stock spa parts, pool heater parts, filters, pumps, jets, chemicals, touchpads, control panels, manuals and more, backed by fast dispatch and practical advice.
Pick-Ups

Pickup for many items is available from our Carrum Downs, VIC store at 10 Industry Blvd, Carrum Downs.
If pick-up is urgent, contact us before ordering.
Our NSW, QLD and WA warehouses currently ship orders only, with no retail counter available yet.

Brand Information

We are an authorised dealer, retailer, and/or service & warranty agent for many leading brands, including: Fluidra (AstralPool, Zodiac, Hurlcon), Aeware, Air Supply of the Future, Aqua-Flo, Balboa, Celsior, CG Air, CMP, Custom Moulded Products (CMP), Darlly, Davey, Del Ozone, Dontek, Edgetec, Emaux, Filtrite, Gecko, Goulds, Harwil, Henden, Herga, Honeywell, HydroAir, HydroQuip, ITT, Jandy, Joyonway, Laing, Len Gordon, Lo-Chlor, LX, LX Whirlpool, Magic Plastics, Magnum, Monarch, Onga, Pentair, PoolSystems, Presair, Raypak, Reemay, Rheem, Rising Dragon, S&P, Sensaheat, Spa-Craft, Spa-King, SpaNet, Spa-Quip, SpaTex, SpaZazz, Tecmark, Therm Products, Thermcore, Waterco, Waterway, Weld-On, Whirlpool, Xylem, and others.

We also sell parts for many spa and swim spa brands, including parts to suit Alpine Spas, Artesian Spas, AquaPulse Spas, Balboa spas, Bullfrog Spas, Caldera Spas, Canadian Spa Company, Cedar Spas, Chinese import spas, Coast Spas, Costco spas, Cyclone Spas, Davey spas, Decina, Designer Spas, Dimension One Spas, eBay spas, Endless® Spas, Fastlane Pools, Fisher Spas, Gecko spas, Halo Spas, H2O Spas, H20 Spas, Heritage Spas, HotSpring Spas, HydroQuip spas, Impact Spas, Jacuzzi, Just Spas, Just Swim Spas, LA Spas, Lanark Spas, Leisurite Spas, Maax Spas, Monarch Spas, MySpa, O2 Spas, Oasis, Sapphire Spas, Sapphire Swim Spas, SCS Spas, Signature Spas, Silver Spas, Spa Industries, Spa-Quip spas, SpaNet spas, Spas Direct, Sundance Spas, Sunrans, SwimEx, Trueform Spas, Tuff Spas, Urban Pool, Vortex®, Vortex® Swim Spas, and many others.

Handy PVC Plumbing Size Info
Plumbing sizes can be confusing. Pressure PVC pipe use nominal sizes - the size is simple a name, not the measured dimension. This convention is used across most pool and spa systems so that pipes and fittings remain compatible.
- 50mm / 2" = ~60-61mm OD
- 40mm / 1.5" = ~48mm OD
- 25mm / 1" = ~33-34mm OD

Plug Types & Styles
Common plug types found on spa equipment are AMP, Mini JJ, C38 (Aus 3-pin), Gecko in.link, etc. For more information please click here.
- AMP plugs are the most common type used for over 20 years.
- Many Mini J&J plugs are no longer available and must be modified.
- C38 is the common Australian 3-pin plug found in normal household outlets.
- Gecko (Aeware) in.link style plugs are no longer available and must be modified.

General Information & Disclaimers

Many products we supply are OEM-supplied and may not include retail packaging, printed instructions, or accessories. Refer to the product listing for details, or contact us if unsure.

Product images are for illustration only. Actual items may vary due to manufacturer changes, updates, and other variations. Images may show a full assembly, a partial assembly, or a specific component only. They are provided for identification purposes and do not by themselves define what is included. Please read the title and description carefully.

All products must be installed and used by qualified and experienced persons in accordance with applicable Australian standards and manufacturer requirements. We are a parts supplier, similar to an electrical, plumbing, or automotive parts supplier. We sell parts, but cannot always provide exact installation, troubleshooting, or system design advice. Buyers are expected to know what they are doing or use a qualified professional.

Contact us before ordering if your order is urgent, to confirm availability before purchasing.

® Trademark Information

All trademarks, brand names, and logos displayed on this website are the property of their respective owners. Heater & Spa Parts is an independent Australian supplier of replacement parts and accessories. Use of trademarked names, logos, and brands is for identification and compatibility purposes only, unless otherwise stated.