Trying to heat water to 99C then activate a small pump

I am trying to heat water to 99degC using a 650W 120V (part number CIR-5032) heating element. I have a PT100 thermocouple to sense the temp. When T=99C I want to turn on a 12V DC pump(3.6W) and turn off the heater. I have an arduino Uno and am looking for help with this project.
I know I will need a relay to turn the heater on/off and probably a 2N2222 transistor to drive the pump. For now I will be using a on/off switch for the whole process with a pressure sensor later applied to turn everything off when I have the basic process working.
Any help is appreciated

I can't comment on the electronics, but just a question.... are you at sea-level? Where I live it's 1800m ASL and water boils at about 94...

yes sea level

Quite sure it will be allot easier to use either a Dallas sensor or a 10kohm or 100kohm thermistor
earlier I tried myself to get one pt100 to work with Arduino though I did not check that recently

It seems otherwise straight forward to implement what you ask for.

Per-Albert

gf870:
yes sea level

Just checking... because if you lived here you would have steam long before you turned it off. That's why automatic kettles switch off based on the steam's pressure tripping the switch, not the water's temperature.

JimboZA:

gf870:
yes sea level

Just checking... because if you lived here you would have steam long before you turned it off. That's why automatic kettles switch off based on the steam's pressure tripping the switch, not the water's temperature.

Are you certain? I thought it was the steam heating up a bimetalic strip that trips the switch.

I'm not certain no... but it can't be temperature since the steam is not at the same temp at different altitudes.

But I just did a bit of Googling and seems you may be right... it is the steam that does it, and the presence of the hot steam indicates it's boiling, as you say. Long as the bi-metallic thingy is insulated from the heat of the body of the kettle, it won't trip until it's boiling.

But whatever, what's inescapable is that water here boils at about 94 and if the OP was here he'd have steam not liquid if he was waiting for 99.

Well using temperature sensor may work fine but keep in mind that the water temperature once boiling starts will no longer increase until all the water is converted to steam vapor. So it would be better to be able to detect the start of boiling condition rather then a specific temperature as just a change in barometric ambient pressure ( a cold front moves in) could lower the start of boiling temperature by a degree or so and you may never turn off the heat and start the pump even though the water is boiling.

Also if this is ever to be operated unattended by people you really should have some form of independent safety shutoff device(s) in case of single point error in the primary control method.

Lefty