Sometimes a leak will show up and you will have no idea where it came from or you think you know where it came from just to find out you were wrong. This is where the skill of troubleshooting comes into play.
With experience comes knowledge and speed when sourcing out a problem. This is because the plumber is able to use past experiences to determine where the leak might be coming from.
In as single family home troubleshooting a problem normally takes between 30 minutes and 2 hours.
The biggest challenge to trouble shooting is you never know what has been done on the other side of the finished wall.
In some cases to find the problem the plumber has to open up a wall or cut into the ceiling. This does not guarantee that is where the problem is but we have to start somewhere. Normally from past experience I decide on what is the most common problem this could be, and I start there. I never start with lets open up a wall just to find a small leak was under your sink the whole time.
The first step to troubleshooting is asking:
Does the leak happen all the time or only when running water in a particular fixture?
This one question tells the plumber whether the leak is on the pressure side or the non pressure side of the plumbing system.
Non-pressure side of your plumbing system includes all drains, shower risers and bathtub takeoffs to the spout.
If the leak only happens when running water the locating the possible fixture can be as easy as looking at a stain on the ceiling and then determining what is above that stain.
The common culprits to leaks showing through onto your ceiling is toilet wax seals, old silicone around the tub or shower. But there are many other possibilities, I just check those first.
Knowing what the common problems are only means you can check those and if that does not solve the problem then move onto something else.
Leaks that I have sourced and fixed over the years”
Wax seal on toilets
silicone around tub
leaky shower tiles
leaky bath drain
no seal around overflow on tub
no seal around shower or bath valve
no seal around bath spout
pinhole leak on copper line cause by electrolysis (when two different metals touch and there is a flow of water an electrical current is created)
split copper line from freezing
failed solder on copper line
nail in copper water line
nails in copper heating lines
nail holes in drain lines
screws in water lines
holes in cast iron
holes in rusted out galvanized pipes and fittings
split poly b lines
burst polyethylene water lines to fridge
split copper manifold
failed pex manifold
These leaks are only the ones that required troubleshooting. Over the years I have repaired hundreds of other leaks that did not require troubleshooting such as under sinks, toilets, water heaters and other leaks in open spaces.
Other trouble shooting problems
no hot water
slow hot water
black sludge in water lines
sump pump problems
Not all plumbing problems that require troubleshooting are emergency plumbing problems. And some emergency plumbing problems do not require troubleshooting.
Cases that require emergency plumbing involve a burst water line that can flood your home or a burst water heater than can flood your basement.
In either case before you call the plumber turn off your water and start to drain your system. By turning off the main water supply and opening a sink valve in the basement you will relieve the water pressure into your sink instead of into you home!
Other emergencies include a failed sump pump. This can quickly cause you a lot of problems and there is nothing you can do except install a new pump and/or use a temporary pump with a hose.
Another emergency is when a drain backs up and floods your basement with fecal matter. You need to resolve this fast.