Plumbing #2 - #3 (Wastewater Systems, Winterizing and De-winterizing,Holding tank monitoring systems) Flashcards
What does CSA Z240 code book say needs to always be behind water when it is flowing?
Air
What is stop drilling?
Stop drilling relieves the pressure on cracks to prevent them from spreading
What is the minimum height you need to extend the vent pipe above the roof line?
2”
How does the sewer hose connect to the termination valve?
With a bayonet connection
What does the CSA Z240 require anytime the sewer hose is not connected?
That a sewer cap must be in place
Where are the holding tanks usually mounted?
They are usually mounted under the floor and drain through termination valves
CSA Z240 code says the termination valve must be where on the RV?
It must be on the left side within 22.5 ft (6.9 m) of the rear of the RV, left of center.
If underneath the RV, what must not be more than 18” (450 mm) from the side wall?
The termination valve
Can termination valves be activated from inside the RV?
No
What is the minimum size hole for grey water discharge?
1-1/2”
What is a grey water tank for?
For holding liquid waste
What are grey tanks typically made from?
Polyethylene or ABS plastic
What is a black water tank?
Body waste holding tank
What tank should you always dump first?
Black water tank
How full should the black water tank be before draining?
At least 75% full
Always make sure that termination valves are what when dumping?
Opened fully
What does the CSA Z240 code state for the minimum size for the black tank drain?
A minimum of 3”
What should you always install with a holding tank sprayer?
A vacuum breaker
How can polyethylene tanks be repaired?
They can be plastic welded or repaired using spin fittings
How can you repair ABS tanks?
They can be repaired using ABS solvent cement or by making a paste by mixing ABS pellets and acetone
You should always do what before performing a repair on a cracked tank?
Always stop drill first
DWV =
Drain, Waste & Vent
What are 2 types of vents?
• Wet vent
• Dry vent
Every water system must have what?
A waste water drainage system consisting of the drain waste and vent (DWV) systems.
What do drainage systems ensure?
That waste water can be safely conveyed to the holdings tanks. And to the tank drain connection.
What are drainage systems composed of?
• Piping
• Fixtures
• Traps
• Fixture baskets and tail pieces
• Valves
• Vents
• Piping systems
• Termination systems
Typically, RVs only have one drain outlet. However, under what clause can the vehicle have separate drain outlets for each tank?
Under clause 7.6. Installation of waste-holding tanks
7.6.1 ( Liquid wasteholdingtank ) - 7.6.2 ( Body waste holding tank)
What does ABS stand for?
Acrylonitrile Butadiene Styrene
What color is ABS piping?
Usually black but can also be white
What location will the type and size of the material be printed on?
Along the pipe.
Where do ABS fittings have the information embossed on?
The plastic
How are ABS piping and connections fitted together?
They are solvent welded together.
What are the 6 steps to making ABS pipe joints?
1) Cut the pipe to the desired length
2) Remove burs and foreign material.
3) Dry fit and mark reference lines
4) Apply cement to both pipe and fitting
5) Assemble while still wet and rotate slightly to align reference marks.
6) Wipe excess cement from the pipe joint.
What does the repair procedure for ABS tanks depend on?
The type of damage
• small fissures
• cracks
• bursts
What does the CSA Z240 code book refer to with code 4.5.4?
Cracks, holes, or other imperfections in materials shall not be concealed by welding or soldering or by paint, wax, tar, or other leak sealing or repairing agents.
What is the minimum vent size for a wastewater system?
The minimum vent size is 1-1/4”
What is the minimum trap size
for a wastewater system?
The minimum trap size is 1-1/4”
What is the maximum slope allowed for a drain pipe inside an RV?
1 in 50 Toward the fixture tee or wet vent.
What is the minimum slope for a tank drainage pipe?
1 in 100 toward the drain outlet
Is a dry vent piping required to have slope since they only pass air?
No
Fixtures refer to what?
They refer to where water from the distribution system is used, including:
• Tubs
• Showers
• Sinks
• Toilets
What are all fixtures, faucets and traps required to be accessible for?
They are all required to be accessible for repair or replacement.
Fixtures must be installed as per their what?
Listing such as The national sanitation foundation (NSF) and the International Association of Plumbing and Mechanical Officials (IAPMO)
What are 5 code standards for fixtures?
• Requirements for rounded corners (to prevent debris build up).
• Strength of floor fixtures
• Slope of fixtures
• Color fastness
• Resistance to cigarette burns
What are the 8 different types of toilets?
• Mechanical seal
• House-type (residential type)
• Composting
• Macerating
• Cassette
• Recirculating
• Incineratation
• Portable
Mechanical Seal toilet
• Most common type used in RVs
• Hand or foot flush
• Must include a vacuum breaker (usually part of the flush valve)
• Must discharge directly into the black tank.
Residential toilet
• Not permitted to be connected to a holding tank.
• Sometimes used in park model trailers without holding tanks.
• Incorporate an S-trap water seal.
• Use 1.5 to 5 US gallons per flush.
Composting toilet
• Waterless system that uses decomposition and evaporation to recycle human waste.
• The composting chamber is directly beneath the toilet and includes a tank to hold the liquid waste. Which needs to be emptied in an appropriate location.
• Solid waste is separated from the liquid and held in the solid waste chamber.
• Aerobic organisms such as bacteria, compost worms, and tiny insects break down the solids.
• A small amount of carbon material such as wood chips, peat moss, astrolabe, coconut fiber, or sawdust must be placed in the chamber to help the sound waste break down more quickly.
Macerating toilets
• Use a macerator pump to grind up the waste and toilet paper. Then, pump the waste to the black tank.
• Can be installed just about anywhere in an RV.
• Type sizing toward the black tank is usually 3/4 to 1 inch.
• Higher water consumption than a mechanical seal toilet
• Require DC electricity to operate
• Most have a tank level sensor to disable the toilet if the tank level is too high.
Cassette toilet
• Can be permanently installed or left as a portable toilet with a waste tank that can be removed and taken to a dump station.
• Water for flushing can be supplied from the RVs potable water system or from a separate tank that is part of the cassette toilet.
• With a permanently mounted cassette toilet, the tank is accessed through a door on the exterior wall of the RV.
• With a portable cassette toilet, the tank is removed from the top of the toilet.
Recirculating toilet
• Does not require a pressurized water source
• Toilet must be filled with 2-3 US gallons of water, which is circulated by either a 12 VoltDC pump or a hand pump during each flush
• Solids are separated and the liquid portion recirculates.
• When the toilet is empty, the water tank must be refilled.
Incinerating toilet
• Burns waste at approximately 760°C (1400°F)
• Uses either a 120 volt AC element or a propane flame.
• The blower sends smoke and fumes outside through the exhaust vent.
• After a cycle, a tablespoon of sterile ash remains.
• A cycle typically takes 45 minutes to 2 hours for electric models. And up to four hours for propane models
Portable toilets
• Requires frequent waste dumping
• Water tank must be filled before first use and after dumping.
• The water enters the ball by a hand pump.
• The water is used for flushing, and the waste is collected in the lower tank.
• Chemicals must be used to control odors.
• When full, the lower tank must be removed and emptied
With cassette, recirculating and portable toilets. Why must care be taken when flushing for the first time after traveling from a low to high elevation?
The flush valve must be opened very slowly to allow the pressure in the tank to equalize to the new elevations air pressure. If it is open rapidly, the toilets contents may geyser upwards with less than desirable results.
When installing mechanical seal toilets the drain connection must be what?
It must be NPS-3”( Nominal Pipe Size ) or greater and must be permanently attached to the drain piping or waste holding tank
What does the CSA Z240 code book state about the water being piped to each fixture?
It states that an adequate quantity of running water shall be piped to each fixture at a flow rate sufficient to flush and keep the fixture clean and sanitary without any danger of backflow or siphonage
Traps
• Trap’s must be installed at every fixture.
• Trap’s prevent sewer gasses and odor from entering the RV through the plumbing system.
• The P-trap is the most common design, which uses a water barrier or liquid seal to block holding tank gasses.
• The CSA Z240 States that traps must be accessible for inspection and repair.
Waterless traps
• A waterless trap is an option if clearance under a tub or shower Pan doesn’t allow room for a P-trap.
• Maintenance includes, inspection of the rubber, bladder, and removal of hair and soap build up.
Fixture Tailpieces
• The sink tailpiece connects the strainer basket and the fixtures trap.
• The connection is made with a compression fitting called a trap adapter.
• Fixture tailpieces can either be single drain tailpieces or double sink tailpieces
Vents are required at every fixture and holding tanks for the following reasons:
• Ensure sufficient air for the flow of liquids.
• Ensure that water is not siphoned from the P-traps.
• Vents allow gasses to escape the wastewater system.
• Vents keep holding tanks at atmosphere pressure while filling or draining.
CSA Z240 Vent codes
• Minimum vent pipe size is 1-1/4 inch.
• An NPS-1-1/2” vent Show not serve more than 4 fixture traps.
• Not more than 3 fixtures are permitted to connect to a wet vent drain system.
• Then pipes extending through the roof must extend. At least 50mm (2 inches) above the roof.
• Vent openings shall be at least 915 mm (36 inches) away from any motor driven air intake.
Anti-siphon trap vent device.
• Used as a secondary vent if the distance between the P-trap and the wet vent exceeds code.
• Must be installed in a location that permits a free flow of air.
• Must be accessible for inspection, maintenance, and replacement.
• The sealing function shall be at least 150 mm (6 inches) above the top of the trap arm.
What are Fittings?
• Fittings connect one pipe to another to extend the length or change the direction of flow.
• Plastic fittings are used to assemble ABS or PVC piping
• ABS and PVC use a solvent cement specific to each. However, transition cement can be used to join ABS to PVC.
• PVC connections require the use of a primer before the cement is applied.
• ABS connects do not require the use of a primer
Fitting angles include:
• 11¼°
• 22½°
• 45°
• 60°
• 90°
Why are vent tees not an acceptable replacement for sanitary tees?
Because the sweep of the tee is important to ensure adequate water flow
Flood testing
CSA Z240 code 9.2.1.4.1
The body waste holding system shall be subjected to a static water test for 15 min by filling the system with water to a level above the connection to the toilet flange without evidence of leaks.
What kind of plastic is Polyethylene?
Thermoplastic ( Will reflow with heat )
What kind of plastic is ABS?
Thermoset Plastic ( Will not reflow with heat )
Flood testing CSA Z240
code 9.2.2 Fixture test
Plumbing fixtures and connections shall be subjected to a flow test by filling them with water and checking for leaks and retarded flow while they are being emptied
Flood testing CSA Z240
code 9.2.1.4.2
The liquid waste holding system shall be subjected to a static water test for 15 min by filling the system with water to the level of the lowest connected trap without evidence of leaks.
Flood testing CSA Z240
code 9.2.1.4.3
The waste piping not tested in Clauses 9.2.1.4.1 and 9.2.1.4.2 in both liquid and body waste systems shall be tested and show no evidence of leakage or retarded flow when the higher fixtures are filled with water and emptied.
What are the two Nontoxic Antifreeze’s used to winterize the potable water distribution system?
•Propylene glycol
•Denatured alcohol
Why do you winterize the plumbing system in RVs?
To prepare for storage in cold weather
What does De-winterizing do?
Prepares the plumbing system for use following the cold weather
What are the 6 steps for winterizing an RV?
1) Drain the water from the fresh tank and water heater
2) Ensure the faucets, shower head, and city water check valve are open
3) Open the low point drains to allow gravity to drain the potable water piping
4) Open the toilet flush valve. Optionally, compressed air connected to the city water inlet can be used to purge the water from the system.
5) After the lines are drained or blown out, close all faucets and valves
6) Add potable water RV antifreeze ( non-toxic ) through the water pump, through the city water inlet, or using the backfill method.
a) If using the water pump method, connect a hose to the pump inlet to draw antifreeze from the container and push it to each fixture. A winterizing bypass can be installed to make the process easier.
b) If using the city water method, use an electric or hand pump to introduce antifreeze into the system through the city water connection.
c) If using the backfill method, use a hand pump to push antifreeze backwards through each faucet. This method is slower and can be messy.
When using the city water or backfill methods, the water pump may not receive antifreeze. How can you ensure it does?
Introduce th antifreeze through the pump.
What are additional appliances that require winterizing?
• Ice makers
• Evaporative coolers
• Washing machines
• Dishwasher
• Remember that the drain lines of some appliances need to be winterized.
How do the chemical compounds in propylene glycol prevent damage in the potable water distribution system?
By not expanding when freezing
Why are glucose based antifreeze’s no longer standard?
Because they rapidly corrode aluminum components.
Why should you never use automotive antifreeze in a potable water system?
Because it contains ethylene glycol, which is toxic to ingest or inhale
Why do you need to add 1-2 cups of non-toxic antifreeze to the P-traps when winterizing the potable water distribution system?
So the P-traps do not freeze
• ( don’t forget the washer and dishwasher )
What are the steps to flush and clean the holding tanks?
1) Drain & rinse grey and black holding tanks, ensure residues are cleaned from the tank walls
2) Drain the black water first so the water from the grey tank can help flush waste from the termination assembly.
3) Close the termination valves and install the cap to avoid pests from getting inside.
4) Add ½ to 1 gallon of antifreeze to each holding tank.
What do the termination valves require if they are leaking or difficult to open or close?
They require either disassembly and cleaning or replacement
What are the 6 steps for De-winterizing the potable water distribution system?
1) Fill the fresh tank and flush the entire system with potable water, starting at the closest fixture to the pump. Don’t forget to flush out the city water connection.
2) When the water runs clear, close the faucets.
3) Un-bypass and fill the water heater.
4) Check for leaks in the entire potable water system, using the pump to maintain pressure in the system
5) Check the drain system for leaks by performing a flood test
a) Fill the grey tank to the lowest fixture ( usually the shower pan or bath tub )
b) Fill the black tank through the toilet until flooded to the closet flange
c) Visually inspect for leaks
6) Service the filtration system, if applicable, by replacing filtration cartridges and checking for leaks.
What problems can arise with Vents?
• Vent piping is usually installed inside walls and cabinets where their location may not be easily identified.
• Vents may be damaged by improperly. Installed screws or other fasteners that penetrate the vent piping.
• Damage can be repaired by cutting out the damage section and installing new piping.
What helps you to know the water level in fresh water holding tanks?
Tank level sensors that are located on the side of the tank.
Wastewater holding tanks monitoring systems are usually the same as what?
Fresh water holding tanks
What does frequently emptying the black water tank do?
You lose the pressure that builds up with a certain amount of waste that helps it flow effectively.
The waste holding tanks should be at least 3/4 full before opening
What are common level readings for tank sensors?
1) Empty, ⅓, ⅔, and full
2) Empty, ¼, ½, ¾ and full
Why should you never leave the termination valves open when connected to a full service campsite?
This causes the liquids to drain away, leaving the solids to build up and solidify.
It’s also important to use quality holding tank chemicals and RV toilet paper.
What are holding tank sensors used to monitor?
They are used to monitor the content levels within the RVs holding tanks.
What are the differences between Type 1 sensors and Type 2 sensors?
•Type 1 sensors: These are probes that protrude into tanks.The probes work by conducting voltage between the ground probe and each tank level probe as the liquid level rises
• Type 2 sensors: These are external to the tank and measure the liquid level in the tank using an inductive sensing strip to read the increase in density as the liquid level increases.
Advantages of Type 1 sensors
• They are usually the simplest type of sensor to install
• They are usually the simplest type of sensor to diagnose and install
Disadvantages of Type 1 sensors
• Waste can build up on the sensor probes, especially if the holding tank chemicals and RV toilet paper are not used
• They may be difficult to replace because they are often spin-welded or cemented to the tank
Advantages of Type 2 sensors
• They are external and don’t have the problem of a build-up of waste or toilet paper
• They are usually easy to install using adhesive strips
Disadvantages of Type 2 sensors
• They are generally more expensive to manufacture
• They are often more technical to diagnose and repair than probe type sensors
What issues can occur with Type 1 and Type 2 sensors?
Type 1 issues
• Electrical connections
• Broken wires
Type 2 issues
• Prone to false readings if the inductive strip is installed too close to metal brackets or frame components.
( Rubber strips can be installed over the metal brackets to eliminate false readings on the monitor panel)
• May be damaged if installed where they are exposed to road spray or debris. In some instances, rubberized undercoating may be applied to protect the sender strip.
