Getting an extract fan to run when the condensor kicks in

[r0ss]

Hi guys,

We've got a little plant room with 2 Toshiba split condensors with duct flexing out the air off the fan and we were wondering if it was possible somehow to have an extract fan kick in when the fan/compressor runs to bring fresh air in from outside. Then when the units turn off, the extract fan turns off?

Thanks,
Ross

[install monkey]

get a pipe stat to kick in when cond coil over 20deg then it will only run if req, or fit a relay piggybacked off the compressor contactor- unless its an inverter then u need to hook off the compressor signal-if low voltage/or pulsed signal then plan b- room stat to sense ambient loft void temp of over 16 degree

[frank]

Toshiba do an add on pcb that will do this....not sure if I recall the accessory correctly but I think its called a T1 or it could be a T2?

[Brian_UK]

Do you want to extract the hot air off the condensers or supply fresh air to them?

[r0ss]

Yeah sorry, should have explained it better. We're already extracting the cold/warm air off the condensers with duct and looking at using an extract fan to supply fresh air, but obviously we don't want the fan to run continuously




Thanks for the other suggestions ill look into them


Cheers
Ross

[frank]

You can always use a current sensing device on one of the compressor wires

If you fan draws more than 1A @ 240V then you could use the sensor to operate a relay/contactor

http://www.electrocontrols.co.uk/product_datasheets/Q02.pdf

[chemi-cool]

I don't think you need an extra fan, All you need is a way for outside air to enter the room while the condenser fan is running, a louver that will open when you extract air, will give you all the supply you need.