Quick Answer: Your Westinghouse iGen4500DFcv won’t start on propane because the fuel selector isn’t fully engaged, the LP demand regulator is frozen, the propane tank’s OPD safety valve has tripped, air is trapped in the propane line, or debris is blocking the LP orifice.
The Westinghouse iGen4500DFcv is a capable dual-fuel inverter generator, but like all propane-equipped engines, it can develop starting issues when switched to LP mode. The good news: most of these problems are diagnosable and fixable without a service call. This guide walks you through the most common causes, in order from simplest to most involved.
At-a-Glance: Most Likely Causes
| Cause | Likelihood | Typical Cost to Fix |
|---|---|---|
| Fuel selector not fully in propane position | Very Common | $0 |
| Air in propane line after fuel switch | Very Common | $0 |
| Propane tank OPD valve tripped | Common | $0–$20 |
| LP demand regulator frozen | Common | $$–$$$ |
| LP orifice blocked by debris | Occasional | $0–$$ |
Diagnostic Walkthrough
Work through these steps in order. Stop when you’ve identified and fixed the problem.
- Check the fuel selector switch. Locate the fuel selector on your iGen4500DFcv (typically on the side of the fuel tank assembly or near the carburetor). Ensure it is fully rotated or pushed to the Propane position—not halfway between gasoline and propane. Listen for a click or feel for a detent that confirms it’s locked in place. If it was in an intermediate position, move it fully to propane and attempt to start the engine.
- Inspect the propane tank’s OPD valve. The Overpressure Shutoff (OPD) valve on your propane tank is a safety device that closes if pressure spikes. If you’ve been running the generator, turned it off, and then switched to propane mode without waiting, the OPD may have tripped. Turn off the fuel selector, wait 5 minutes, then slowly reopen the propane tank valve (the hand knob on top of the tank). You should hear a faint hiss as pressure equalizes. Try starting again. If the OPD trips repeatedly, the tank may need to be serviced by a propane supplier.
- Bleed air from the propane line. When you switch from gasoline to propane mode, air can become trapped in the fuel line between the tank and the carburetor. This air prevents liquid propane from reaching the engine. Locate the small bleed screw or fitting on the LP demand regulator (a brass or aluminum component mounted near the fuel line). Using a small wrench or screwdriver, slowly open this fitting until you hear a faint hiss of propane escaping, then close it tightly. This purges air from the line. Wait a few seconds and attempt to start the engine.
- Warm the LP demand regulator if it’s frozen. In cold weather or after extended storage, the LP demand regulator can ice up internally, blocking fuel flow. This is more common if your generator sits outdoors in winter. Gently warm the regulator by pouring warm (not boiling) water over it, or wrap it with a heat pad set to low. Do not use a torch or direct flame. Allow it to warm for 10–15 minutes, then attempt to start. If freezing is a recurring problem, you may need to replace the regulator with a cold-weather-rated unit.
- Check the propane tank pressure. If you have a propane tank pressure gauge (or can borrow one), connect it to the gauge port on your propane tank. A healthy tank should read between 100–150 psi at room temperature. If pressure is very low (below 50 psi), the tank may be nearly empty or have a leak. If pressure is extremely high (above 200 psi), the OPD may be malfunctioning. In either case, have the tank inspected by a propane supplier.
- Inspect the LP orifice for blockage. The LP orifice is a small jet inside the carburetor that meters propane fuel. Debris, rust, or carbon buildup can clog it. Access requires removing the carburetor, which is a moderate DIY task if you’re comfortable with small-engine work. Once removed, locate the orifice (a tiny brass fitting or hole) and look for visible debris. You can gently clean it with a soft brush or compressed air, but do not poke it with a wire—you’ll enlarge the opening and cause the engine to run rich. If cleaning doesn’t help, the carburetor may need a professional rebuild.
- Test the ignition system. Even if fuel is reaching the carburetor, the engine won’t start without a spark. Check that the spark plug is clean and properly gapped (typically 0.028–0.032 inches for small engines). Remove the spark plug, inspect the electrode for fouling or heavy carbon buildup, and clean or replace it if needed. Reinstall and try starting again. If the engine still won’t turn over and you hear no starter motor sound, the ignition coil or starter may be faulty—this is beyond fuel delivery and requires professional diagnosis.
- Verify the propane tank valve is fully open. The hand-operated valve on top of the propane tank must be fully open (turned counterclockwise until it stops). A partially closed tank valve will starve the engine of fuel. Ensure it’s not stuck or corroded. If it’s difficult to turn, do not force it; have a propane supplier service it.
Parts You May Need
- Spark plug (Champion or equivalent, model-specific)
- LP demand regulator (if frozen regulator cannot be thawed)
- Carburetor rebuild kit (if orifice is severely blocked)
- Propane tank OPD valve replacement kit (if OPD is defective)
- Fuel line and fittings (if line is cracked or leaking)
- Heat pad or warm water (for thawing frozen regulator)
When to Call a Pro
Stop troubleshooting and contact a certified small-engine technician or Westinghouse authorized service center if:
- The fuel selector is stuck or won’t move to the propane position without excessive force.
- You detect a propane smell coming from the fuel line, regulator, or tank connection—this indicates a leak that requires professional repair.
- The OPD valve trips repeatedly even after you’ve waited and reset it.
- The propane tank pressure gauge reads dangerously high (above 250 psi) or the tank is visibly damaged or corroded.
- After bleeding the line and warming the regulator, the engine still won’t turn over and you hear no starter motor sound.
- You’re uncomfortable removing or inspecting the carburetor.
- The engine starts briefly on propane but immediately dies or runs very rough.
Frequently Asked Questions
Why does my iGen4500DFcv start fine on gasoline but not on propane?
Propane and gasoline require different fuel delivery systems. The propane circuit includes a demand regulator, orifice, and fuel line that are separate from the gasoline carburetor circuit. If any component in the propane path is frozen, blocked, or misadjusted, the engine won’t start on LP even if the gasoline side works perfectly. The most common culprits are air in the line after switching fuels, a frozen regulator in cold weather, or the fuel selector not being fully engaged.
How long does it take to bleed air from the propane line?
Bleeding the line usually takes less than a minute. Open the bleed screw on the LP demand regulator slowly until propane gas hisses out, then close it immediately. You should hear propane escaping for just a few seconds. Wait 10–15 seconds for the line to repressurize, then attempt to start. If air is still present, repeat the process once more.
Can I use my iGen4500DFcv in freezing temperatures on propane?
Yes, but you may experience starting difficulties if the LP demand regulator freezes. Propane itself remains a liquid at temperatures well below freezing, but the regulator’s internal mechanisms can ice up, blocking fuel flow. If you operate your generator in winter, keep the propane tank in a sheltered location, allow extra warm-up time, and consider installing a cold-weather regulator designed for sub-zero operation. Never attempt to thaw a regulator with an open flame.
What does it mean if the propane tank OPD valve trips?
The OPD (Overpressure Shutoff) valve is a safety mechanism that closes if internal tank pressure exceeds safe limits—usually due to excessive heat or a rapid pressure surge. If you’ve been running the generator hard and then immediately switched to propane mode, thermal expansion in the tank can trigger the OPD. The fix is simple: turn off the fuel selector, wait 5 minutes, then slowly reopen the tank valve. If the OPD trips frequently without an obvious cause, the tank may have a defect and should be inspected by a propane supplier.
Disclaimer
This article provides general troubleshooting guidance for the Westinghouse iGen4500DFcv dual-fuel inverter generator. Always consult your model-specific owner’s manual and follow all manufacturer safety instructions before attempting repairs. Propane is a flammable gas; if you detect a propane leak or smell, stop work immediately, move to a well-ventilated area, and contact a qualified technician or your propane supplier. Do not attempt repairs you are not confident performing, and never force stuck components. When in doubt, seek professional service from an authorized Westinghouse dealer or certified small-engine repair shop.
Source: Information adapted from official manufacturer documentation (reference). Always consult your generator owner’s manual for model-specific procedures.