Small tanks under office sinks, heaters tucked into attics and ceilings, and tankless units in restaurants and breweries: what we replace, what we repair instead, and how the work fits around a business that has to stay open
Most of the commercial water heaters we replace around Everett are not big boilers. They are small electric tanks under office sinks, heaters tucked into attics and ceiling spaces, and tankless units serving restaurants and breweries. The work usually takes part of a day, and the planning matters more than the tank: access, shutoffs, permits and business hours.
1. Point-of-use heaters under sinks and in attics
Older commercial buildings often heat water right where it is used, with a small tank under a sink or above a restroom, because the main heater is far away or there is none. Those tanks fail out of sight. In December 2025 a downtown Everett office building called us about a water heater alarm, and Logan and Connor replaced two six-gallon electric heaters that afternoon. The first sat under a second-floor office sink; they reconnected it with flexible supplies and fitted a new ball valve for it, laid out to suit the cramped cabinet. The second sat in the attic space above the public office's restroom, where it now rests in a drain pan with a leak alarm beside it. While they were there they rebuilt both office toilets and fixed a leak at a hand-washing sink, so all of it was done in one visit.
2. Tankless cascades in restaurants and breweries: repair before you replace
Restaurants and breweries often run two or more tankless heaters side by side, sharing the load. When one of them acts up, the answer is often a part. In May 2026 a brewery in Mukilteo called about a loud slam from its pair of Navien tankless units, and when Logan and Chase arrived, the second unit was showing an E003 code. They could not make it slam on demand, so they worked through the fault with Navien's technical support and replaced the flame rod assembly and the ignition transformer. The old flame rod had been sparking outside its assembly instead of inside the burner. Their read on the slam was delayed ignition: the unit called for gas, failed to light at once, and then lit a chamber holding too much gas. With the new parts in, both units fired with no error codes.
3. Heaters nobody can see: check the power first
A heater hidden above a ceiling is easy to forget until the hot water stops. In January 2026 a sports center near Lynnwood had no hot water, and the first task for Logan and Connor was finding the heater: a Rinnai tankless behind a plywood wall just inside an access panel in the kitchen ceiling. It had no power. A tripped breaker in an upstairs utility closet was the whole problem, and once they reset it the Rinnai fired and hot water came back to the kitchen below. A replacement would have cost the owner a new heater for a problem a breaker solved.
4. Tenant improvements: the heater rides on the permit
When a commercial space is reworked, the water heater is part of the plumbing permit like everything else. In February and March 2026, at a commercial building on the Highway 99 corridor north of Lynnwood, Carlos and Logan installed a water heater the owner had supplied while they rebuilt the waste and water for two existing sinks, added a utility sink, re-piped the heater, cleaned up the water lines with a stop at each sink and put the new rough-in on test. The owner asked us to pull the plumbing permit, so the job included the submittal, the review and the inspections.
5. Replacement on your schedule, not the heater's
A small tank that leaks, trips its alarm or rusts at the base is a replacement, and the sooner it is done the less it costs in water damage. The difference between an emergency and a routine job is usually just the timing. A planned swap can be booked for a quiet morning, with the parts on the truck and the shutoffs found in advance, so the business loses hot water for hours rather than days.
Commercial Water Heater Questions
How long does it take to replace a small commercial water heater?
For a point-of-use tank under a sink or in an attic, usually part of a day. At a downtown Everett office in December 2025, Logan and Connor replaced two six-gallon heaters, rebuilt two toilets and fixed a sink leak in one afternoon. Larger tanks, tight access and new venting take longer, which is why we look before we quote.
Our restaurant's tankless keeps showing an error code. Does it need replacing?
Not usually. An error code points at a part, and the fix is often a sensor, an igniter or a flame rod rather than a new heater. At a Mukilteo brewery in May 2026, an E003 on one of two Navien units came down to the flame rod assembly and the ignition transformer, and both units fired cleanly afterward.
Do commercial water heater replacements need a permit?
In most cases, yes. In Everett a water heater replacement is permitted through the City's Permit Services, and a tenant improvement brings its own plumbing permit, review and inspections. When a commercial owner north of Lynnwood asked us to handle that paperwork in 2026, the job included the submittal, the review and every inspection.
We have no hot water and cannot find the heater. Where do we start?
Start with the breaker. A heater hidden above a ceiling or behind a wall is easy to forget, and a tripped breaker looks exactly like a dead heater. At a sports center near Lynnwood in January 2026, Logan and Connor found a Rinnai behind a plywood wall above the kitchen ceiling, reset its breaker and had hot water back.
Our Recommendation
Treat small commercial heaters like any other piece of equipment. Know where every one of them is, label its breaker, keep its access clear and give each tank a shutoff of its own. Have tankless units serviced on a schedule, and call when one throws a code rather than when it quits. When a tank does need replacing, book it for a quiet morning, and plan the permit alongside it if the space is being reworked.
Commercial Water Heaters, Handled
Call the office, tell us where the heater is and, if you can, send a photo of its label. We will tell you what the visit involves and how much of the day the building will be without hot water.
Call 425-374-3909 · Request a Quote
Related: commercial plumbing services · commercial plumbing in Everett · commercial plumbing in Mukilteo · commercial plumbing in Lynnwood · plumbing for property managers · prevailing-wage plumbing for public buildings · water heaters · tankless water heaters
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