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solenoid valve control Answered

hi, im wanting to build somthing simple to control the heater control valve on my fiesta. its a simple solenoid valve at 0v its open(hot) at 12v(14.4v) its closed(cold) the propper control board uses pulses to control the valve, the board has since given up and im left with a very hot car, now i thought a simple way to sort the problem might be to use the 10k pot on the control board with a MOSFET and just vary the voltage going to the valve. will this have the same effect on the valve?


No, you need something to pulse the solenoid - its either open or closed, and can't be partly open. That said, it needn't be hard to do, just a 555 timer.

why cant it be partly open? on the hydraulic units at work we use proportional controls on the solenoids that dont use pulses.

Because its not a 500 quid hydraulic proportional valve, its a cheap, (probably <10 quid) piloted on/off valve because that's all it needs.

Ah ok. Ive got a load of 555.s knocking about ill have a bash

Hmm, stevelee and steveastrouk, any relation? :D