RV Winterization Service Checklist for Shops

Winterizing is the one RV service where a mistake stays hidden for months. A rig leaves in the fall looking perfect, and the split water line or cracked water heater shows up in spring. Jayco’s owner’s manuals put the stakes plainly: repairs resulting from freezing are not covered by warranty.

This checklist is for shops that want winterization done the same way on every rig, by every tech, with proof. The procedural details come from RV and appliance manufacturer manuals. Plumbing layouts differ between models, so treat it as the standard your shop works to and the unit’s own manual as the final word.

Before you start: what the manuals agree on#Link to the section “Before you start: what the manuals agree on”

• Only RV antifreeze. Jayco and Thetford both say to use RV (potable) antifreeze only. Jayco warns that automotive antifreeze (ethylene glycol) and windshield washer antifreeze (methanol) are toxic and potentially fatal if ingested.
• Keep antifreeze out of certain components. Jayco’s towable manual says antifreeze should never enter the tank water heater, the RV water filter, the refrigerator, the refrigerator water filter or the fresh water tank.
• Appliances need their own procedure. Jayco’s Class C manual says the refrigerator, dishwasher and clothes washer must be winterized according to each appliance’s manual.

Step 1: Drain the fresh water system#Link to the section “Step 1: Drain the fresh water system”

1. Turn off the water heater at both the gas and electric switches.
2. Level the rig, open all faucets including the outside shower, and drain the fresh water tank through its drain valve.
3. Open the low-point drains, which Jayco describes as typically labeled and located at the lowest point of the water lines.
4. Flush the toilet until water stops flowing.
5. If you run the water pump to push out the last of the water, Jayco says to run it only until dry, typically 15 to 20 seconds, to avoid damaging the pump.

Step 2: Bypass and drain the water heater#Link to the section “Step 2: Bypass and drain the water heater”

Tank water heaters have bypass valves so that antifreeze and sanitizer don’t fill the tank. Jayco’s manual describes the bypass position as diverting water around the heater; set it before any antifreeze goes in. How you drain the tank depends on the heater:

• Suburban tank heaters drain through the anode rod opening or a drain plug. Suburban’s guidance is to turn the heater off and let it cool, drain the tank, and use the bypass if you’re using RV antifreeze. If there is no bypass and antifreeze will be added, Suburban says to remove the anode rod, store it for the winter and fit a 3/4-inch drain plug, because antifreeze can be very corrosive to the anode.
• Dometic (Atwood) tank heaters drain through a drain plug. If the water trickles, Dometic’s manual says to open the temperature and pressure relief valve to let air in and clear the drain opening with a small wire. It notes that about two quarts stay in the tank because of where the plug sits, and that this water will not damage the tank if it freezes.
• On-demand (tankless) heaters have no bypass line, so Jayco notes that antifreeze passes through them. The heater must be off, and its own manual governs draining and freeze protection.

The drained tank is also the moment to look at the anode on a Suburban. Suburban recommends checking the anode every 6 to 12 months and replacing it when more than 75% of it has been consumed. Photograph it and quote the replacement as its own line.

Step 3: Choose the method: antifreeze or blow-out#Link to the section “Step 3: Choose the method: antifreeze or blow-out”

Jayco’s towable manual calls the antifreeze method preferred and also documents an air pressure method. Offer the methods your shop is equipped for, and note that the blow-out method still puts antifreeze in the drain traps and some appliances need antifreeze either way. Whatever you do, write the method on the work order.

The 30 PSI figure is Jayco’s; check the manual for the unit you’re working on. When you blow out lines, Thetford says to keep the toilet’s water valve open to avoid damage.

Step 4: Appliances and fixtures#Link to the section “Step 4: Appliances and fixtures”

• Washer or washer-dryer. Splendide’s winterization instructions for its front-loading washer-dryers put antifreeze in the machine itself: with power off, pour half a quart of RV antifreeze into the drum, run a spin setting for one to two minutes, then unplug it, turn off the supply faucets, disconnect the inlet hoses and drain them. Splendide gives a separate procedure when antifreeze is being pumped through the whole system, and newer models have their own manuals.
• Refrigerator ice maker and water dispenser. Keep antifreeze out of the refrigerator and its filter, as Jayco instructs, and follow the refrigerator manufacturer’s procedure for the water valve and supply line. Procedures differ between makes and models.
• Dishwasher. Follow the appliance manual, per Jayco’s Class C manual.
• Toilet. Thetford’s Aqua-Magic manual describes a draining method (turn off the water, drain the bowl, disconnect the supply line at the water valve and drain it) and an antifreeze method using RV antifreeze only.
• Macerator. If the rig has one, Jayco’s Class C manual includes it in winterization; follow the unit’s procedure.

Step 5: Holding tanks#Link to the section “Step 5: Holding tanks”

Jayco’s storage checklist says to drain and flush all holding tanks before storage, dumping at an appropriate facility or as local regulations require. Then put one cup of RV antifreeze in each drain P-trap so the water left in the traps can’t freeze.

Step 6: Batteries#Link to the section “Step 6: Batteries”

Jayco’s storage checklist tells owners to remove all batteries and store them somewhere they won’t freeze. How to keep them healthy in storage depends on the chemistry:

• Lead-acid. Trojan Battery states that a battery can only freeze if it is left partially or completely discharged, and that freezing does irreparable damage to the plates and container. Its guidance is to charge fully before storage and give a boost charge when the battery shows 70% charge or less.
• Lithium (LiFePO4). Battle Born recommends storing its batteries fully charged in an environment above freezing if possible, disconnected from the system, and says its batteries will not accept a charge when their internal temperature is below 24°F.

For any battery, follow the maker’s storage guidance and note the state of charge on the work order.

Step 7: Propane#Link to the section “Step 7: Propane”

Jayco’s storage checklist says to close the propane cylinder valves and cover the regulator. If an owner asks you to store cylinders, the National Propane Gas Association’s safety guidance, published by New Jersey’s Division of Codes and Standards, says not to bring propane cylinders indoors or into an enclosed space such as a garage or basement, and to store them upright, outdoors and away from ignition sources.

Step 8: Everything else on the storage list#Link to the section “Step 8: Everything else on the storage list”

The same visit is the right time for the rest of the storage prep in Jayco’s checklist:

• Inspect the roof and surfaces for damage and potential leaks. Our roof inspection guide covers what to check.
• Retract the slide-outs; the slide-out maintenance guide covers seals and storage.
• Close windows and roof vents, cover the roof air conditioner, and seal entry points for rodents and insects.
• Turn off and clean the refrigerator, and leave its doors propped open.
• Add fuel stabilizer to the generator, if equipped.

The winterization checklist#Link to the section “The winterization checklist”

Print it, or better, build it into your inspection template so every tech runs the same list:

• Water heater off at gas and electric; cooled; pressure relieved at the relief valve
• Fresh tank drained; low-point drains opened; all faucets and outside shower opened
• Water heater bypassed (antifreeze method) and drained; anode inspected on Suburban units
• Water filter cartridges removed
• Lines filled with RV antifreeze to every faucet, hot and cold, or blown out at the manual’s pressure
• Toilet winterized per its manual; valve held open during any blow-out
• Washer, dishwasher and ice maker winterized per their manuals
• Holding tanks dumped and flushed; one cup of RV antifreeze in each P-trap
• Drains closed, plugs reinstalled or tagged as removed
• Batteries charged, disconnected or removed, and state of charge recorded
• Propane cylinder valves closed and regulator covered
• Roof inspected; slide-outs retracted; vents and windows closed
• Method, valve positions and removed parts written on the work order and on a tag inside the coach

Price it and document it as a seasonal service#Link to the section “Price it and document it as a seasonal service”

Winterization is easier to quote and to explain as a defined package with add-ons than as a single vague “winterize RV” line. One structure for the estimate:

• A base winterization line for each method you offer, priced from your own labor rate.
• RV antifreeze as a material line, by the gallon used.
• Add-on lines for a washer, dishwasher or ice maker, battery service or removal, and anode replacement.
• A roof inspection and slide-out seal check, offered on every winterization.

In RVDesk, canned jobs keep that package identical on every estimate, and the customer approves each line from a link, so a declined add-on is recorded rather than forgotten. Build the checklist above into a digital inspection and your techs fill it in on a phone with photos: bypass valve positions, the drained heater and anode, antifreeze at the farthest faucet, the battery. Those photos stay with the job, which matters if a customer calls in April about a leak.

Bring them back in spring#Link to the section “Bring them back in spring”

The fall visit should set up the spring one. De-winterizing is its own service:

• Flush the antifreeze from the lines, reinstall the water heater plug or anode, set the bypass to normal, close the drains and reinstall the filter.
• Run the washer through Splendide’s de-winterizing step: an express cycle with detergent to clear antifreeze.
• Sanitize the fresh water system. Jayco recommends sanitizing at the beginning and end of each season, using a 50 ppm solution of 1/4 cup of household bleach per gallon of water, one gallon of solution for every 15 gallons of tank capacity, left in the system for at least four hours, then flushed until the chlorine smell is gone.
• Reinstall and charge the batteries, and have the propane system leak-checked, which Jayco’s travel checklist recommends.
• Check the roof and slide seals for winter damage.

The simplest way to get the spring visit is to book it before the rig leaves in the fall, while the customer is standing at the counter. For reminders, keep the messages within what the customer agreed to. CTIA’s messaging principles treat appointment reminders as informational messages the customer agrees to when they give you their number for that purpose, while promotional messages, such as a spring special, call for express written consent. RVDesk’s two-way texting sends from your shop’s own registered number, replies land against the customer and the job, and a customer who replies STOP can’t be texted by mistake.

Want to see a winterization package go from canned job to approved estimate to a photo-backed inspection? Book a demo and we’ll set it up around your shop’s seasonal work.