No. 100 psi is too high for a residential irrigation blowout. Keep poly pipe at or below 50 psi, PVC at or below 80 psi and drip lines at 20–30 psi, or lower if a component manufacturer requires it.

My small home compressor reads 120 psi — is it enough?

It may have enough pressure, but small home compressors usually lack the air volume (CFM) needed for a full sprinkler system. A high tank reading doesn't mean it can keep the outlet airflow steady.

What happens if water stays in the pipes?

Water expands as it freezes and can crack pipes, sprinkler heads and valves. A proper blowout clears the zones before the first hard freeze.

When should I do my blowout in the GTA?

Before the first hard freeze, typically October to early November. Watch the forecast rather than waiting for a fixed date.

Do you offer a guarantee?

Yes. The Freeze Guarantee comes with every HigreenWall fall closing: freeze breaks found at a HigreenWall spring opening are fixed free.

Which gauge should I watch during the blowout?

Watch the outlet or regulator gauge. It shows the pressure going into your pipes. Read the long, thin needle end on the inner red psi scale, not the short counterweight or the tank gauge.

HigreenWall · Fall field guide

What PSI is right for a sprinkler blowout?

Quick answer

For most homes, use about 50 psi at the regulator: poly pipe 40–50 psi (max 50), PVC 50–60 psi (max 80), and drip lines 20–30 psi. Read the long, thin end of the needle; 1 bar ≈ 14.5 psi. More pressure does not clear more water and can damage pipes and heads.

By Ardeshir Adiban, HigreenWall technician

Last updated: October 2026

Which pressure gauge matters for a sprinkler blowout?

Outer black numbers are bar; inner red numbers are psi. 1 bar ≈ 14.5 psi, so 4 bar ≈ 58 psi. For this guide, use the inner psi scale.

These are general ranges, not a guarantee for every system. Follow the lowest pressure limit specified for your pipes, heads, valves and backflow device. If the pipe type is unknown, don't assume PVC limits apply.

Book my fall closing

Outlet pressure55 psi ≈ 3.8 bar

0 psi150 psi

OK for PVC (white rigid pipe), max 80

How do I read a compressor pressure gauge?

1
Two scales. One pressure.
Outer black numbers are bar; inner red numbers are psi. 1 bar ≈ 14.5 psi, so 4 bar ≈ 58 psi. For this guide, use the inner psi scale.
4 bar ≈ 58 psi
2
Follow the long, thin end.
Read the long pointer, not the short, thick end. That short end is a counterweight. It may point near 200 while the actual reading is about 55 psi — it isn't a second reading.
Wrong end
Right end
55 psi ≈ 3.8 bar
3
Tank pressure isn't outlet pressure.
The tank gauge shows stored air. A compressor normally fills to about 120–150 psi before shutting off. The regulator gauge shows what goes into your pipes — that's the number that matters.
Set the regulator, not the tank pressure.

What PSI should I use to blow out sprinklers?

Sprinkler blowout pressure ranges and limits
Pipe / equipment	Working pressure	Maximum	Notes
Poly pipe	40–50 psi	50 psi	Black, flexible pipe · never above 50 psi
PVC pipe	50–60 psi	80 psi	White, rigid pipe · maximum 80 psi
Drip lines	20–30 psi	—	Low-pressure tubing · 20–30 psi
Compressor tank	120–150 psi	—	Let it fill completely before starting so outlet pressure stays steady.

For homeowners in Toronto and the GTA, plan your fall closing before the first hard freeze.

What happens if you use too much air pressure?

Air volume (CFM — cubic feet per minute) moves the water out, not high pressure. Too much pressure after the water is gone can create friction heat that melts or cracks fittings, damages sprinkler heads and valve diaphragms, and harms the backflow preventer.

If airflow isn't enough, don't raise the pressure. Run each zone in short bursts and let the tank recover. The compressor needs enough air volume for the system, not just a high number on its gauge.

How do technicians safely blow out sprinklers?

Turn off the water supply first.
Keep at least one zone open — never pressurize a closed system.
Start at 40 psi for sprinkler zones; increase only if heads don't pop up, within the component limits. Drip zones need just 20–30 psi.
Use short bursts per zone; let the tank recover between bursts.
Stop when the heads spray only a fine mist — don't keep running dry air.
Release the air and leave valves in the correct position for the equipment at the end.

Don't blow compressed air through a backflow preventer. Use the appropriate downstream connection and follow the device manufacturer's winterization instructions. Wear eye protection and stay clear of heads under pressure.

Doing it wrong can mean expensive repairs in spring — this is why most homeowners let a pro do it.

FAQ

Is 100 psi too much for a sprinkler blowout?

Still unsure about something? Call or text and we'll answer it straight.

No. 100 psi is too high for a residential irrigation blowout. Keep poly pipe at or below 50 psi, PVC at or below 80 psi and drip lines at 20–30 psi, or lower if a component manufacturer requires it.