Predictive maintenance for the sauna heater

A heater that fails in the middle of a booked session is bad business. Unhappy guest. Refund. And an electrician on an emergency call-out at full price.

Predictive maintenance turns that around. Instead of waiting for the heater to fail, you see it coming, and replace the element on a day you choose.

Three ways to maintain

• Reactive: you fix the heater once it has failed. Cheapest on paper. Most expensive in practice, because it fails when it's used most.
• Preventive: you replace parts on a fixed interval. Safer. But you often throw out elements with plenty of hours left.
• Predictive: you replace based on the heater's actual condition. Most out of every element, and no surprises.

What you measure

It sounds advanced. It's three measurements.

Power draw

An element nearing the end of its life draws current differently. Follow the power over time and you see the deviation before it becomes a failure. A heater that suddenly draws more or less than usual is speaking up in its own language.

Leakage current

This is often the earliest warning of all. When the insulation around an element breaks down, usually because it has absorbed moisture or the sheath is about to crack, current starts leaking to earth. A little at first. Then more.

Measure this and you catch the element long before it trips the earth-fault breaker or fails mid-session. It's as much a safety measurement as a maintenance one. Rising leakage current is exactly the kind of fault that otherwise develops in silence.

Session count

Add how many sessions the heater has actually run, and how hot it got. Then you have real wear, not a guess from the calendar. Two saunas bought on the same day can be worlds apart if one runs twice as much.

From numbers to a job on the calendar

The point is that the measurements become one concrete message: "The element in sauna 3 should be replaced within a couple of weeks." You order the part, find a gap with no bookings, and do the job as planned. Not on a Friday night.

It's also fire safety. A heater that's monitored doesn't get to develop a fault in silence.

Worth most when you have several

If you run several self-service saunas, this is the difference between control and firefighting. You see which heaters are approaching maintenance, and plan your round around it.

How Ulmatic does it

Ulmatic measures power and leakage current on every heater, follows the trend over seven days, and adds the session count. You get a verdict in plain language, not a number in milliamps. And you fix it when it suits you. Before the guest notices anything.