Patio Heater Has No Gas Flow? Here's How to Diagnose It

Patio Heater Has No Gas Flow? Here's How to Diagnose It

You hook up a full propane tank, turn the valve, try to light the heater — and either nothing happens or you get a tiny flame that dies immediately. The fix depends on what type of heater you have. Here's how to work through it correctly.

First: Figure Out Which Type of Heater You Have

The most common cause of no gas flow is different depending on whether your heater uses a pilot tube or not.

  • Older tall heaters and most pyramid heaters use a pilot tube — a small metal tube that carries gas to a standing pilot flame. These are the most common type and the most common cause of no gas flow on these is dust, debris, or a spider web clogging the pilot tube or orifice — especially after sitting in storage over winter.
  • Newer heaters without a pilot tube use direct ignition. On these, if the tank and hose check out, the regulator is more likely to be the issue.

If you're not sure which type you have, look for a small metal tube running from the gas valve up toward the burner. If you see it, you have a pilot-style heater.

Step 1: Check the Tank

Before anything else — is the tank actually full? Propane tanks don't run out gradually. Pressure stays consistent until the tank is nearly empty, then drops suddenly. Pick it up and shake it. If it feels light or hasn't been refilled recently, try a fresh tank first.

Also check that the tank valve is fully open — turned counterclockwise until it stops. Partially open valves are a surprisingly common cause of weak or no flame.

Cold weather is another factor. Below about 40°F, a tank under a quarter full may not generate enough pressure. A fuller tank or bringing it inside to warm up fixes it.

Step 2: Check the Hose

Run your hand along the hose between the regulator and heater. Look for kinks, sharp bends, or visible cracks. A kinked hose restricts flow as effectively as a broken part. Straighten it out or replace it if it's damaged.

Step 3: Clean the Pilot Tube and Orifice (Older and Pyramid Heaters)

If you have a pilot-style heater — which includes most older tall heaters and virtually all pyramid heaters — this is the most likely cause of your problem and it's completely free to fix.

Over winter storage, spiders, insects, and dust get inside the pilot tube and orifice and block gas flow. Even a partial blockage is enough to prevent ignition or cause a very weak flame.

With the propane tank fully disconnected:

  1. Locate the pilot tube — the small metal tube running from the valve to the burner area.
  2. Use a can of compressed air to blow out the pilot tube from the burner end. A short, firm blast is usually enough.
  3. Also blow out the pilot orifice — the small brass fitting the pilot tube connects to.
  4. If compressed air doesn't clear it, a thin piece of wire or a guitar string can be used to gently clear the orifice opening. Do not use a drill bit — the orifice is precisely sized and damaging it will cause other problems.
  5. Reconnect the tank and try again.

This fixes the majority of no-gas-flow issues on older heaters and pyramid heaters. It should always be the first thing you try on these units.

Step 4: Try the Regulator Reset (Newer Non-Pilot Heaters)

On newer heaters without a pilot tube, if the tank and hose check out, the regulator bypass may have tripped. This happens when the tank valve is opened too fast, causing a pressure spike that triggers the safety mechanism. It's not common, but it's worth a two-minute try before replacing anything.

  1. Turn the heater control knob to OFF.
  2. Close the tank valve completely.
  3. Disconnect the regulator from the tank and wait 30 seconds.
  4. Reconnect hand-tight.
  5. Open the tank valve slowly — a quarter turn at a time. Opening it fast will trip it again immediately.
  6. Try to light the heater.

Step 5: Replace the Regulator

If the reset didn't work and you've ruled everything else out, the regulator itself is worn out. This is more likely on newer non-pilot heaters. It's a straightforward swap and one of the cheaper parts on the heater.

Last Resort: The Gas Valve

If you've worked through everything above and still have no gas flow, the gas valve itself may have failed. This is rare — valves are durable and usually outlast everything else on the heater. But it does happen on older units. At that point, the most practical fix is to replace the entire burner head assembly rather than just the valve, since you're already dealing with an older unit and the head may have other worn components too.

What If It Lights But Won't Stay Lit?

That's a different problem. If the heater lights and then shuts off after you release the knob, you're dealing with a tilt switch or thermocouple issue — not a gas flow problem. See our guide on heaters that won't stay lit.

Summary

For older heaters and pyramid heaters: clean the pilot tube and orifice first — it's almost always debris. For newer non-pilot heaters: check the tank and hose, then try the regulator reset, then replace the regulator. The gas valve is a last resort, and at that point a full burner head assembly is usually the smarter fix.

Wano Co sells genuine OEM replacement parts for Hampton Bay, Master Forge, and Gardensun patio heaters — sourced directly from Gardensun, the original manufacturer. Free shipping on all orders.

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