This may sound a bit weird but I have bought my self a 125mm 365m3/h RUCK high power fan as a intake. The problem is it seems to be sucking in air faster then my extraction fan can get rid of it. I'm using a RVK 150mm 660m3/h for my extraction with a Can carbon filter.

I do have a Primair controller but if the temp goes above 27c which I have it set to everything goes pear shaped.

Is the intake fan I have got a bit of over kill ? or can it be tweaked do you think ?

¿Couldn't you swap the intake and exhaust fans around if that's the case - or otherwise get a fan speed controller?

50% that is alot, i didn't realise it would reduce it that much.... I'm still learing as I go as this is my first grow.

Swapping them round isn't really an option as the filter is 150mm. The primair will control the speed but its when the temp in the tent goes above the max I have it set to the intake blows too much and the exhaust doesn't suck enough

I take it that your RVK is the L1 model, if you say it's rated at the above flow. If it is, then with a CF attached it should should be extracting something like 480m3/hr. That obviously is greater than the 365m3/hr that the intake Ruck is doing.

Having said that, if there is more significant resistance on the extract duct, like several bends, long duct length, obstructions or reductions it could bring the flow to below the Ruck fan rating.

If it does then its either too small or knackered

Bends and length of duct can drastically reduce flow but not the cf itself to that extent

Owd

I would like to help you more on CF resistances, but I've had no success in trying to get performance curves from CF manufacturers. Seems to be top secret. Any one else find them I would really appreciate contact details. Every other manufacturer will supply vent designers with resistance Vs air flow details.