Comparisons

 Rainmaker® Buyer’s Guide: 1/2" vs. 3/4" Brass Impact Sprinkler HeadsChoosing the right sprinkler head depends entirely on the size of your property, your available water supply, and your pump capacity. Both heads are built from premium, heavy-duty brass to withstand intense fire-season heat, but they are engineered for different scales of defense. [1]Use this guide to find the perfect fit for your bushfire protection system.At-A-Glance ComparisonFeature1/2" Impact Head3/4" Impact HeadInlet Size1/2" Male Thread3/4" Male ThreadFrontage CoverageUp to 15 MetresUp to 30 MetresWater Flow Rate15 Litres Per Minute (LPM)30 Litres Per Minute (LPM)Required Pressure350 KPa350 KPaRecommended Spacing10 Metres apart15 Metres apartBest Used ForStandard residential homes & roofsLarge rural blocks, acreage & boundariesDetailed Breakdown1/2" Brass Impact Head: Best for Standard Residential SetupThis head is ideal for residential properties, suburban roof ridges, and medium-sized yards.

• Water Efficiency: At 15 LPM, it consumes half the water of the larger model, making it gentler on limited tank water supplies.
• Easy on Pumps: Because it requires less flow, standard 5.5HP–6.5HP firefighting pumps can easily run multiple 1/2" heads simultaneously without losing critical pressure.
• Layout: Spaced at 10 metres apart, they provide a strong, overlapping blanket of water perfect for protecting typical rooflines and asset protection zones.

3/4" Brass Impact Head: Best for Acreage and Large Scale DefenseThis high-volume head is engineered for large rural properties, long boundaries, and expansive asset protection zones.

• Massive Range: With a huge 30-metre frontage coverage, it throws water twice as far as the 1/2" model, cutting down on the total number of sprinkler heads and pipework you need to install.
• High-Volume Drenching: Blasts 30 LPM of water to rapidly raise local humidity and knock down heavy ember attacks before they near your structures.
• Pump Demands: This is a heavy-duty commercial head. Running multiple 3/4" heads requires a high-capacity single-impeller or twin-impeller firefighting pump and a substantial water supply. Spaced at 15 metres apart, they create an impenetrable barrier of water.

Which One Do You Need?Choose the 1/2" Impact Head if:

• You are mounting them directly onto a standard residential home roof or gutter line.
• You have a limited water tank storage capacity and need to stretch your water supply as long as possible.
• You want to run a system of 4 to 8 sprinklers simultaneously using a standard firefighting pump.

Choose the 3/4" Impact Head if:

• You are protecting a large rural block, shed, or boundary line fence facing open bushland.
• You have a massive water supply available (such as a swimming pool, large dams, or multiple large water tanks).
• You want to cover a very wide area using fewer sprinkler units and want maximum water density to fight intense heat. [1]

Check condition of O ring seal, Screw the head into the body and tighten until the O ring is compressed.  If o ring leaks the attempt to reset it or add thread tape to the tread.

 If the arms stop spinning there may be a blockage in the sprinkler. Simply disassemble, flush out all parts to clear any debris and reassemble.