Yes it can be replaced, if it is of the replaceable type. If you are in doubt about how to do it, perhaps you should have it done by a Plumbing professional.
In general a water heater will only last so long.The major problems are with the thermostat and the heating element.You'll have to replace the thermostat occasionally.If the heating element goes out it's time for a new water heater.
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You can go to hometips.com
When my heater didn't work i had to replace my thermostat.
Of course a water heater thermostat would be defective as water heaters / hydronic boilers would use an Aqua Stat
No, BUT they do have an AQUA stat
Someone turned up the thermostat, or the thermostat has failed. The thermostat tells the heater what temp to keep the water at.
replace anti-freeze, replace thermostat
You may need to replace your Thermostat or your Heater Core.
First thing you should check is the antifreeze level. If that is fine, replace the thermostat. If it still over heats after the thermostat, then most likely you need to replace the waterpump. If your antifreeze is low, check for leaks, the radiator, hoses, heater core, and water pump. If the water pump is leaking, that is your problem, replace that and thermostat all in one.
Two good indicators of when to replace the car's thermostat: * When you have to run the heater (no matter what time of the year) in order to keep the engine coolant from overheating, * When you no longer get ANY heat from the heater core.
The heater core is plugged. The thermostat is stuck closed. Antifreeze/coolant level is low. The water pump is not working properly. Check the cheapest things first. Check fluid levels. See if the fluid is circulating well. If okay, replace thermostat. If still cold replace heater core.