Before you begin
Gather the equipment recommended in your owner’s manual, work in a safe and well-lit area, and check campground rules before using shared utilities or facilities.
Step-by-step instructions
1 Step 1
Read the RV, water heater, pump, filter and plumbing manuals first. Confirm which components must be bypassed or isolated.
2 Step 2
Choose a location where you may legally drain and refill the fresh-water system. Drain old water using the manufacturer’s procedure.
3 Step 3
Remove or bypass filters that could be damaged by sanitizing solution; follow the filter maker’s instructions.
4 Step 4
Prepare an approved sanitizing solution at the exact concentration and contact time specified by the RV or plumbing manufacturer. Never guess bleach quantities.
5 Step 5
Introduce the solution into the fresh tank using the manufacturer-approved fill method, then circulate through cold and hot fixtures only if the manual calls for it.
6 Step 6
Allow the solution to remain in contact for the specified time; keep the system out of drinking-water service during treatment.
7 Step 7
Drain and flush thoroughly with potable water until the manufacturer’s procedure is complete and the system is safe for use.
8 Step 8
Reinstall or replace filters as required, inspect for leaks and label the date of sanitizing in your maintenance log.
Detailed Canadian RV guide
The following practical details expand on the quick steps above. Equipment differs between motorhomes, fifth wheels, travel trailers and truck campers; use the instructions for your particular RV and components whenever they differ.
When sanitizing is appropriate
Sanitize the fresh-water system after long storage, after a suspected contamination event, or according to your RV manufacturer’s maintenance schedule. Persistent unusual odour, slime or discoloured water warrants investigation; sanitizing cannot fix a damaged or contaminated tank indefinitely.
Read the RV, pump, filter and water-heater instructions first. Some components must be bypassed or treated differently. Never mix chlorine bleach with vinegar, ammonia or other cleaners.
Prepare the system
Drain old water into an approved location and inspect the tank fill, vent and hoses. Remove or bypass filter cartridges as directed by their manufacturer because disinfectant can damage them or be removed by them.
Use plain, unscented household bleach of a known sodium-hypochlorite concentration only if the RV maker specifies bleach sanitization. Concentrations differ, so do not assume one universal cup-per-tank formula is correct.
Mix and circulate safely
Calculate tank capacity and follow the manufacturer’s exact disinfectant dose, dilution method and contact time. Pre-dilute as instructed rather than pouring concentrated bleach directly onto sensitive parts. Fill with potable water and run each fixture until treated water reaches it, including hot and cold lines where applicable.
Keep the RV ventilated and avoid splashing bleach onto fabric or metal. Do not drink the solution or run appliances in a way that conflicts with their manuals.
Flush and verify
After the specified contact period, drain to an approved sanitary location where local rules allow. Refill and flush with potable water until the manufacturer’s process is complete and disinfectant odour is no longer objectionable. Reinstall approved filters and check all fittings for leaks.
If you need microbiological assurance after contamination, use a qualified water-testing service; clear appearance and lack of odour alone do not prove water is safe.
Prevent future contamination
Use a dedicated potable-water hose, cap the tank fill, avoid questionable sources and clean hose fittings. Do not top up from a spigot marked non-potable, even through a consumer filter.
Store the RV water system according to seasonal recommendations. In freezing climates, drain and winterize as instructed so standing water does not damage plumbing.
Sanitizing before the season
Sanitize at the start of the season and after long storage. Use the manufacturer’s recommended bleach ratio, flush thoroughly and follow local health guidance.
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