Leaking Water Heater at a Commercial Property or Apartment Building

The water heater closet floor is wet. Sometimes it's a damp ring around the base, sometimes a pan that has overflowed, and sometimes the first sign is a stain on the ceiling or wall of the unit next door. Water heaters sit in utility rooms nobody checks often, so a leak can run for a while before anyone sees it.

Not every leak means the tank is finished. Water can come from the supply and outlet fittings on top, the temperature and pressure relief valve, the drain valve near the bottom, or the tank itself. The first four can be repaired. A leak from the tank body, usually from the bottom, means the steel has failed from the inside and the unit is done.

We start by shutting off the water to the heater, and the gas or power if it's safe to do so, then dry everything and trace where the water starts. Looking at the top, the relief valve and its discharge pipe, the drain valve, and the base in that order sorts most cases quickly.

A relief valve that drips can be a worn valve, or it can be doing its job because pressure or temperature in the tank is too high, so we look at why before replacing it. A leak that only shows when the unit is heating points to pressure. A steady leak from the bottom with a rusted jacket points to the tank.

If the leak is at a fitting, the drain valve or the relief valve, we replace the failed part and check that it stays dry once the tank is heated.

If the tank itself is leaking, repair isn't possible, and we recommend replacement. We replace tank water heaters at businesses and apartment buildings as well as at homes, and we haul the old unit away. Replacement involves sizing the new unit for the load, connecting water, gas or power, venting where it applies, and, depending on the city, a permit. We tell you which applies before we start, and the proposal is yours to approve first.

Shut off the cold water supply to the heater if you can reach the valve, and turn off the power or gas control if it's safe. If you smell gas, leave the area first, then call 911 and Southwest Gas. Move anything stored near it. If water is spreading to neighboring units or electrical equipment, shut off the main and call us right away. We offer 24/7 emergency service.

Tell us the approximate age, whether it's gas or electric, and roughly what it serves, such as one suite, a restroom or a whole building. If a leased space is involved, ask who owns the heater under the lease before approving work. For apartments, tell us how to reach tenants who will be without hot water.

The same steps apply: shut off the water, then look at where it starts. A drip from a fitting or valve is usually a repair. Water coming from the bottom of the tank means it's time to replace it.