HR15 Humidifier. No Stat, No Tank

The HR humidification kit comes complete with a 100lt space saver tank, an inline 13mm to 6mm filter, a metre of 13mm and 6mm pipe and either an analogue or digital humidistat. The Centrifugal Humidification Systems are ideal for indoor growing. Not only will it help you to ensure an optimum level of relative humidity (50-75%) in your grow room. HR15 • 1500cc per hour • Coverage 15m2 – 30m2 • 4-6 lights • Size 31 x 31 x 47cm HR50 • 2500cc to 4000cc per hour • Coverage 100m2 – 150m2 • 10-15 lights • Size 37 x 37 x 48cm Available with digital or analogue Humidistat.


The HR-15 is a tried-and-tested, professional grade humidifer that takes water from a reservoir tank and releases it into the air as vapour, maintaining optimal humidity levels. With a 1.5 litre / hour emission rate, it’s ideal for those running larger grow rooms.

  • Check out our complete kits with header tanks and reverse osmosis filters
  • Very easy to install – just connect it to a header tank (sold separately)
  • Increases moisture levels in the grow area by up to 1.5 litres per hour
  • Covers grow rooms of up to 30m2
  • Accelerates plant growth rates by delivering an optimal environment
  • Available with either an analogue or digital hygrostat, which automatically switches the unit on and off as required
  • Not to be used with hard water
  • Can be used to regulate VPD using the Intelligent Humidity Controller


1 x HR-15 Humidifier with no hygrostat, or with an analogue hygrostat, or with a digital hygrostat. Please make your choice in the drop-down menu above.

Recommended additional purchase

Quick Connection Kit – connects the HR-15 to a header tank

How HR-15 Humidifers Work

As plants transpire, they lose water through their stomata (small openings on leaf surfaces). If the moisture levels in the surrounding atmosphere are too low, then the volume of water released by plants through their stomata will be higher, which can have very negative impact (wilting, stress and poor health). Boosting the level of moisture in the atmosphere, when necessary, will have a huge impact on plant growth and vitality.

The HR-15 connects to a tank, which supplies water to the unit. It works via a float switch system, so that water is only ever sent to the unit when it is needed – it will never overflow. No pump is required, as it’s a gravity fed system. The HR-15 can then be plugged into a hygrostat, if you have chosen to buy one with it. The hygrostat then plugs into the wall. The hygrostat will then regulate the HR-15 so that it only ever introduces moisture into the air when it needs to.

It should be noted that the HR-15 is designed for use with water that has been filtered through a reverse osmosis unit. Filtering water removes excess salts that can damage internal components and cause issues in your growroom. These salts can even corrode your reflectors, causing a drop in yields. If you wish to use this unit with unfiltered water, you do so at your own risk. We cannot except returns and the manufacturers will not send out a replacement. Check out our complete kits with header tanks and reverse osmosis filters​ 

How to Use the HR-15

The HR-15 will need to be connected up to a header tank. We recommend purchasing a quick connection kit, which comes with everything you need for the job.

You should also note that this unit will require a two-pin to three-pin adapter.