Nexgrill 720-0888S Manual Walkthrough: Assemble It Right, Then Fix What Goes Wrong

Nexgrill 720-0888S Manual: What You Actually Need Before You Start

If you are reading this with a half-built cart in the driveway and a hardware bag that already spilled onto the concrete, you are in the right place. This walkthrough reconstructs the assembly sequence and the troubleshooting logic most owners need from the Nexgrill 720-0888S manual - the 4-burner propane grill with a side burner, battery push-button ignition, heat tents, and a 20 lb tank bracket. It is written for the homeowner who has assembled a grill before (or replaced a trusty one that finally rusted through after nine seasons), not for someone who wants a spec sheet.

Two things before you touch a bolt. First, verify you have the correct manual revision. Second, give yourself a clear two-hour window. In practice, a single person should budget 60-90 minutes; two people who split the firebox lift typically finish in 45-60 minutes. Newer revisions ship hardware in blister packs labelled by step number, which shortens inventory to about five minutes instead of twenty.

Confirm You Have the Right Manual: 720-0888 vs 720-0888S vs 720-0888N

The 720-0888 family includes several suffixes - 720-0888, 720-0888A, 720-0888N, and 720-0888S - and they share enough parts diagrams that people routinely download the wrong PDF. The suffix matters most for lid finish, trim, and a handful of fastener sizes. The “S” in this family generally denotes the stainless-lid variant. Downloading the base 720-0888 document when you own an S model is the single most common reason a build stalls at the side shelf step.

Where the Model and Serial Number Live on a 720-0888S

Open the left cabinet door or look at the rear cart panel near the tank opening. Nexgrill usually places a rating plate there listing the full model number, serial number, gas type, and manifold pressure. Photograph it before you start assembly - you will want it for a parts order or a support call, and it is far easier to read now than after the firebox is bolted down.

Tools, Time, and a Two-Person Plan for the Firebox Lift

You need a Phillips screwdriver, an adjustable wrench or a socket set, a utility knife for box flaps, and a muffin tin or four paper cups for sorting hardware. A second adult is not optional for Step 4 - the firebox is the heaviest single component, and it is the number one cause of pinched fingers and scratched stainless lids.

Step-by-Step Assembly: Cart and Casters First, Firebox Last

Step 1 - Inventory the Hardware Pack Before Touching a Bolt

Lay every bolt, washer, and pin out on a towel and match them to the parts list. If your revision uses numbered blister packs, keep each pack with its step. Missing hardware is far cheaper to resolve by phone before assembly than after you discover it at Step 6.

Step 2 - Build the Cart Frame With Bolts Snug, Not Tight

Assemble the base panel and side panels with every bolt threaded loosely. Tighten everything only after all four corners are joined and the frame sits flat on the ground. Fully tightening the first joint locks the frame out of square and produces a wobbly cart with misaligned doors that no amount of later torque will fix.

Step 3 - Locking Casters, Fixed Casters, and the Grease Tray

Locking casters go at the front, fixed casters at the rear. Slide the grease tray into its rails before the firebox goes on - it is much easier to seat cleanly while you still have open access. Confirm the tray slides freely; a jammed tray is usually a bent rail from the shipping box, not a defect.

Step 4 - Mounting the Firebox: The Step That Scratches Lids

Two people lift the firebox onto the cart and set it squarely before inserting any fasteners. Keep the lid closed during the lift, tape a scrap of cardboard over the stainless edge if you are working on concrete, and start all four bolts by hand before running them down. Cross-threading here is the most common reason a lid sits crooked.

Step 5 - Side Shelf and Side Burner Gas Tube Connection

Attach the side shelf, then route the side burner gas tube to the manifold and thread the flare fitting by hand first. This joint is the most common leak origin on this grill, and forcing a cross-threaded fitting strips the flange. Snug it with a wrench - one quarter turn past hand-tight is plenty.

Step 6 - Heat Tents, Cooking Grates, Warming Rack, Tank Bracket

Drop the heat tents (flavorizer bars) over each burner tube, then set the cooking grates and warming rack. Install the tank retention bracket so a 20 lb cylinder cannot tip. The regulator hose should be a Type 1/QCC1 connection - hand-tighten the coupling nut only, then check it during the leak test.

Step 7 - AA Battery Orientation and the Igniter Wire

The push-button module takes a single AA battery. Fit it with the flat negative end against the spring, then confirm the igniter wire is seated on the collector box beside the leftmost burner. A reversed battery is silent; a disconnected wire clicks but never sparks at the electrode.

Step 8 - The Soapy-Water Leak Test at Every Joint

Mix dish soap and water, brush it onto the tank valve, regulator coupling, manifold connection, and side burner tube joint, then open the tank valve slowly. Bubbles that grow mean a leak - close the tank, reseat the fitting, and retest. Do this before the first cook and again at the start of every grilling season.

Step 9 - First Fire: Burn-Off Before the First Cookout

Close the lid and run all burners on high for 10-15 minutes to burn off manufacturing oils. Expect some light smoke and a faint smell - that is normal. Let the grill cool, then wipe the grates before your first cook.

Eight Assembly Mistakes That Cost 720-0888S Owners an Afternoon

• Fully tightening bolts before the cart frame is square - wobbly cart, misaligned doors.
• Skipping the soapy-water leak test because the grill is brand new.
• Opening the tank valve fast, tripping the excess-flow device, then blaming a bad regulator.
• Installing the AA battery backwards.
• Bending the igniter electrode while wiping the firebox during cleaning.
• Using the wrong-size bolt on the side burner gas tube flange and stripping it.
• Covering a warm grill - condensation accelerates corrosion.
• Assuming a field natural-gas conversion is possible; it generally is not without an approved kit, so check with Nexgrill support first.

Compare Two Nexgrill Models Side by Side Before You Commit

If you are still deciding between the 720-0888S and a griddle or pellet model in the same lineup, the build itself is only half the decision. Try comparing two products side by side below to see which fits best.

Once You've Weighed Two Grills, Here's What Else Matters on the 720-0888S

Assembly is the easy half. The harder half is the Saturday morning when you planned a Sunday cookout and the grill will not cooperate. The table below maps the symptoms 720-0888S owners report most often to the actual cause and the fix - no guessing, no replacing parts you did not need.

Symptom-to-Fix Table: Ignition, Flame Quality, and Heat Problems

The Igniter Clicks but Nothing Lights: Electrode Gap and Moisture

If you hear the tick but no flame, the spark is jumping somewhere other than the burner. Pull the cooking grates and heat tents, inspect the electrode tip for grease bridging or condensation after a rainy night, and reset the gap to roughly 1/8 in (3 mm). A bent electrode from aggressive grate scrubbing is a common culprit.

No Click at All: Battery, Module, and Collector Box Checks

Work from cheapest to most expensive. Swap the AA battery and verify orientation. Then check that the wire from the push button is snug on the collector box next to the leftmost burner. If both are fine and the module is silent, the module itself is the likely failure point.

Weak Flame After a Tank Swap: Resetting the Excess-Flow Device

This is the most misdiagnosed problem on any propane grill. When you crack the tank valve open quickly, the excess-flow device sees the pressure spike and restricts flow, leaving you with a weak flame that looks exactly like a failed regulator.

Yellow, Sooty Flame and the Burner Air Shutter

A yellow flame with black soot on the grates means incomplete combustion. Adjust the air shutter on the burner toward more air and clear any blockage in the venturi. A properly adjusted burner burns blue with a short, steady flame.

Spiders, Venturi Nests, and Why Southern Grills Fail in Spring

In the U.S. South and Midwest, spiders and mud daubers nest inside burner venturi tubes during the off-season. The first spring cook then runs weak or yellow. Pull each burner once a year, look through the tube, and clear it with a bottle brush before reassembling - this single habit prevents most “my grill lost all its heat” complaints.

Grease Fire Protocol: Lid Closed, Burners Off, No Water

Replacement Parts: What Wears Out First on a 4-Burner Nexgrill

In order of typical failure: heat tents (flavorizer bars), then burner tubes, then the igniter electrode and module, then the regulator hose assembly. Heat tents often fail in two to four seasons with heavy use, while a well-kept burner tube can last longer. Keep the model and serial number handy when ordering.

Natural Gas Conversion on the 720-0888S: What Not to Attempt

Field-converting a propane 720-0888S to natural gas by drilling out orifices is unsafe and generally not supported. Manifold pressure and orifice sizing differ, and an unapproved conversion can produce dangerous incomplete combustion. If natural gas matters to you, contact Nexgrill support about approved options rather than improvising.

DIY or Call Nexgrill Support? A Decision Block

• DIY: battery, electrode gap, igniter wire, excess-flow reset, air shutter, venturi clearing, heat tent replacement.
• Support: cracked manifold, stripped side burner flare fitting, regulator/hose replacement, any suspected leak you cannot isolate, and any conversion question.

Saturday Morning, Sunday Cookout: A Realistic Repair Timeline

A battery swap or excess-flow reset takes ten minutes. An electrode cleaning and gap reset is a thirty-minute job with cool-down time. Ordering replacement heat tents or burners usually takes several days, which is why the Saturday-before check matters - inspect the firebox, clear the venturi, and test ignition a full day before guests arrive. A failure you find on Saturday is an errand; the same failure on Sunday is a takeout order.

Sources

• Nexgrill Contact & Support
• Nexgrill About Us
• Nexgrill All Products
• U.S. Fire Administration - Cooking Fire Safety
• NFPA - Grilling Safety Tips