Repairs, replacements, and the three safety details that get skipped: the T&P valve, the expansion tank, and where the discharge pipe ends.
A temperature and pressure relief valve is the only thing standing between a stuck thermostat and a tank of water heated well past boiling under pressure. It opens at around 150 psi or 210°F, whichever it reaches first. A tank that fails without one does not leak; it releases all of that energy at once, and the results are the reason this valve exists in every code in the country.
So when one weeps, the fix is never a cap, a plug or a tightened seat. Anybody who caps one should be off the job. Usually a weeping valve is not even a faulty valve — it is the valve doing its job, telling you about a pressure problem somewhere else.
Water expands when you heat it, and it is not compressible. In an old open system that expansion simply pushed back into the city main and nobody noticed. Modern systems are closed: a check valve or a pressure-reducing valve at the meter means the expansion has nowhere to go. So every heating cycle raises the pressure in your pipes, sometimes dramatically, until the weakest relief point lifts — which is the T&P valve on the tank.
The cure is an expansion tank: a small vessel with a rubber diaphragm and an air charge that gives that expansion somewhere to go. It has to be sized for the tank and, crucially, its air charge has to be set to match your actual incoming static pressure, which means measuring the incoming pressure first. A tank fitted with a factory 40 psi charge onto a 70 psi supply is already fully waterlogged and does absolutely nothing, and there are a great many out there in exactly that state, bought and fitted and useless.
We check incoming pressure static and running on every water heater call. If it is above 80 psi, that is a pressure-reducing valve conversation as well, because pressure that high shortens the life of every fixture, hose and appliance in the house.
The pipe from the relief valve carries the one warning you are ever going to get, so it has to deliver that warning somewhere a person will see it. That means it runs downhill for its whole length with no trap and no upward section, stays the full size of the valve outlet with no reduction, uses no valve of any kind, and terminates near the floor — low enough that scalding water discharging does not land on somebody — with a plain unthreaded end so nobody can cap it later.
What we find instead: a pipe run up into a ceiling and off into a wall, a pipe terminated inside the drip pan under the tank where a slow discharge just evaporates, a pipe reduced from three-quarter to half inch, a pipe with a threaded end and a cap sitting on it. Each of those turns a warning into a secret, and the point of the warning was that you had time to act on it.
Inside a tank, two things decide its remaining life: sediment and the anode rod. Sediment is mineral that settles on the bottom and, on a gas heater, sits between the burner and the water, which makes the heater work harder and the steel run hotter. The rumbling or popping some tanks make is water flashing to steam under that layer. The anode rod is a sacrificial magnesium or aluminum rod that corrodes so the tank does not; it is consumable, it is checkable, and replacing one at the right time genuinely extends the life of the tank. Almost nobody looks at it, and it is one of the few pieces of maintenance on this list that plainly pays for itself.
Tankless is an excellent product oversold. It gives you endless hot water and takes up no floor space. It also needs a considerably larger gas supply and vent than a tank heater, so a retrofit is often not a swap but a gas line and a vent as well; it needs descaling on our water here, on a schedule; and it does nothing at all for how long you wait for hot water at a distant fixture, which is the complaint people most often hope it will fix. When we quote one we will say what the real installed cost is including the gas and the venting, and if a tank is the better answer for your house, we will tell you that.
Dielectric unions or proper connectors where copper meets the steel tank fittings, because the galvanic corrosion at that joint is a common cause of a heater that looks like it is leaking from the tank when it is leaking from a nipple. And, on a gas unit, the venting — draft, connector slope, and whether the water heater is sharing a closet with something that competes for combustion air. That last one is a life-safety check, and it is not billable, and we do it anyway.
Request a visit and the office will call you back to agree a time. We measure before we price, and you keep the readings.
Scripted demonstration. It cannot book, hold or confirm a time, and it will not quote a price.