All guides

Self-leveling lap sealant on horizontal roof seams, non-sag on vertical, Eternabond on long cracks, Geocel on sidewalls, never silicone. Matched to roof type.

Water enters at a seam and travels along framing before it shows. Use a pin moisture meter, a bottom-up hose test, and the nine common entry points to find it.

Most first-trip trouble on a new travel trailer is tire pressure, lug torque, and an untested brake controller. The 12 checks in order, driveway to first night.

A 6 gal Suburban on gas heats from cold in roughly 20-25 minutes by the spec-sheet math, about 45 on electric alone, and about 15 with both running.

Add up amp-hours per day for each device, divide into your bank's usable capacity, and you have your answer. Typical draws for 14 common loads inside.

A 20 lb cylinder holds about 430,000 BTU. Divide by each appliance's rated BTU/h and its real run time and you have your answer. Here is the spec-sheet math.

Undo the bypass and drains, pressurize slowly and look for splits, flush the antifreeze, then sanitize with 1/4 cup of bleach per 15 gal of tank, 4-12 hours.

A rested voltage reading tells you state of charge; only a load or capacity test tells you if the battery is worn out. Here is the order, with the tables.

Drain tanks and water heater, bypass the heater, then blow lines out at 30-40 psi or pump 2-3 gal of RV antifreeze through. Step order, quantities, checklist.

Swapping to lithium usually means a new converter profile, a better fuse at the battery, and a DC-DC charger if you tow-charge. Here is what changes and why.

Most rooftop RV air conditioners that drip inside have clogged drain holes in the base pan or a gasket that lost compression. Here is how to tell them from a rain leak.

When an RV battery won't charge on shore power, the usual cause is a blown reverse-polarity fuse on the converter, a disconnect switch, or a bad connection.

Black tank sensors read full because paper and scale bridge the probes. Flushing with a rinser or wand and a softener soak clears most; external sensors fix it for good.

When the freezer works but the fresh-food box stays warm, the usual causes are level, poor rear ventilation, a missing baffle, or a thermistor out of place.

An absorption fridge that cools on 120 V but not on gas almost always has a dirty burner, a clogged orifice, or a flue full of rust flakes. Here is the order.

An RV furnace that blows cold air and quits is usually a sail switch or limit switch dropping out, not the board. Here is the test order with the readings.

An RV furnace blower pulls 7-11 A, so a cold night can use 30-50 Ah, more than a single Group 24 can safely give. Here is the math and the fixes, by cost.

Most RV furnaces that blow but never light have low voltage or a sail switch that isn't closing. Here is the test order, with the readings to expect.

Most slide-out leaks come from a flattened bulb seal or a torn wiper at a corner. How to inspect, measure, and replace them, and when a slide topper pays.

Most slides that won't retract have low battery voltage, a tripped breaker, or an interlock. Check those, read the controller code, then use the override.

Most RV toilets that won't hold water have scale or grit under the flush ball or blade seal. Clean the groove first; most seals don't need replacing.

Drain a Suburban or Atwood RV water heater cold and depressurized, flush it, replace the anode at about 75% consumed, and refill fully before power goes on.

An RV water heater that won't light on gas is usually a tripped ECO, air in the line, or a dirty electrode. Here is the Suburban and Atwood test order.

An RV water pump that cycles with every faucet closed is losing pressure to a leak or a failed check valve. Here is the test order and the pressure specs.

An RV water pump that runs nonstop is usually pumping from an empty tank or into an open valve or leak. Check the tank, then the fixtures, then the switch.

A 7-pin plug that won't charge the trailer battery usually has an unpowered 12 V pin: a missing fuse or relay in the truck. Here is the pin-by-pin test.

Most trailer sway traces back to tongue weight under 10 percent of the loaded trailer. Three ways to measure it, with the math, and how to shift weight forward.

Most half-ton trucks run out of payload long before towing capacity. How to read the yellow door label, what counts against it, and three worked examples.

Most weight-distribution hitch trouble is bars set by feel. The fender-height measurement sequence from the hitch manuals, with the numbers to write down.

An RV that beeps at night is usually the propane detector chirping on low battery voltage, a CO or smoke alarm at end of life, or an inverter low-battery alarm.