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Replacement Hot Water Thermostats
The thermostat controls when your electric booster element switches on and at what temperature it stops. A failed thermostat either leaves you with no hot water at all, or lets the tank run dangerously hot.
✔ Signs your thermostat has failed
- No hot water from the booster, even though the element tests fine
- Water scalding hot, or the relief valve discharging regularly
- Booster running constantly and driving up power bills
- Thermostat has tripped on manual reset and won't stay reset
✔ What we stock
- Robertshaw thermostats at 60, 70, 75 and 80 degrees, including automatic reset (50–70°) and Solahart and Rheem-specific models
- Cotherm 350mm 4-pole thermostat to suit Chromagen solar hot water systems
- Universal hot water thermostat, adjustable 50–80 degrees
- Rheem, Solahart and Edwards thermostat conversion kit, including solar Robertshaw automatic reset thermostat
- Hills screwed-element systems — combined 1 1/4" BSP Incoloy element and thermostat kit
- Clamp thermostat assemblies, bolt-on clamps, protective covers and Cotherm ring terminal wire sets
✔ Choosing the right one
Match the temperature rating, the mounting type (clamp-on, bolt-on or immersion), and the pole configuration. Solar systems often need an automatic reset thermostat rather than a standard one — if you're replacing like for like, check the part number on the old unit.
⚠ 240V component
Fitting must be done by a licensed electrician or plumber.
✔ Not sure which rating you need?
Email sales@solarhotwaterparts.com.au with the part number from the old thermostat and we'll match it.
