Wiring up 2 or more 220V axial fans

[Joule57]

I'm a complete novice. Can someone draw me a simple diagram showing how to properly wire up 2 or more 220V axial fans. in series and in series parallel .
Also I purchased an infrared spa from china and some of the lamps stay on after the session times out. I'm assuming stick relay on the circuit board? The problem is intermittent.
Are circuit board components typically irratic due to the USA utilizing 60 hertz as opposed to 50 hertz (rest of the world) and how much of a voltage variable is acceptable . Will these components work ok at 335 volts ?
Any input is greatly appreciated .

 

[AnalogKid]

AC fans cannot be wired in series. Also, the fans are not polarity sensitive (there is no plus or minus input) so any straight parallel connection is safe. The fans won't care about 50 or 60 Hz, but might run faster on 60 Hz.

ak

 

[Bluejets]

Where did the 335V come from?

 

[Joule57]

I'm sorry, typo. 235v

 

[Joule57]

So fans aren't sensitive to hertz but might circuit board components be? Trying to figure out why the lamps on this spa intermittently stay on after the digital timer zeros out. Could it be a faulty relay in the board ?

 

[AnalogKid]

Definitely maybe. Photo of circuit board?

ak

 

[Bluejets]

So fans aren't sensitive to hertz ?

Read #2 again.........

 

[duke37]

The motors are probably simple induction motors and without load will run at a speed proportional to frequency. When driving a fan, things are more complicated since the fan torque is proportional to speed squared and the power is proportional to speed cubed. It would make an interesting experiment if sufficient power were available at different frequencies to see the frequency effect.

I see no difficulty in running two fans in series so long as they are identical and double the voltage is applied.
I see no difficulty in running two fans in parallel as long as sufficient current is available.

Most circuit board components work on DC which is derived from some sort of power supply. Asking components to run above their rared voltage is a sure way of killing them. Using a transformer at a lower than rated frequency could also cause trouble.