FURNACE & DUCT CLEANING · SINCE 1947
Furnace and duct cleaning in Yakima, the trade on Theisen's first trucks
The 1950s Theisen trucks were lettered FURNACE CLEANING, and that is still in the company name. The vacuum goes through a window and the furnace, filters and ducts come out clean.
Chapter 01
What a dirty furnace and clogged ducts do to a house
Dust does not stay in the filter. It settles on the furnace, in the smoke pipe and along the ductwork, and a system working through that is working harder than it has to. Theisen puts the ductwork side plainly on its own service list: clogged ducts can lead to poor air circulation and pose a fire hazard for your home or business.
Most of it is also quiet. Nobody sees inside a duct, and the first sign is usually a room that never quite warms up or a furnace that sounds tired in January. One Angi reviewer admitted the only problem was that the air filters had not been changed recently enough, and the technicians were kind about it and left tips on furnace upkeep.
Furnace cleaning is where the company started, and it is the one service where the name on the old truck says exactly what the crew does: clean the furnace, the filters and the smoke pipe, then the ducts.
A dark Theisen Furnace Cleaning truck parked in a field, its door lettered with the phone number GL 24787.
How the vacuum truck work goes
The method is in the old wooden tag shown below: a power vacuum cleaner, the filters, and the smoke pipe. Today the same idea runs from a vacuum truck parked outside, with the hose fed into the house. In one review it went in through a window. A Yelp reviewer in 2019 wrote that the crew “cleaned the ducts thoroughly and even cleaned the dirt from the window they put the vacuum through.”
Reviewers describe the crew arriving early, not rushing and explaining as they go. A Google reviewer in 2024 wrote that Zack did a great job on the ducts, answered questions and did not rush the job. An Angi reviewer in 2015 called the vacuum truck an awesome piece of modern equipment and said the laundry room was cleaner than they found it.
A cleaning visit is also a free look at the rest of the system. Another Google reviewer had ducts cleaned and the heating system serviced in one trip, and the crew noticed her air scrubber was not working and got it fixed. Furnace cleaning and heating service sit side by side at Theisen, so a problem found on the way through does not need a second company.
Chapter 03
How often, and what to do between visits
Theisen generally suggests a routine service every other year. One Yelp reviewer has the shop out at the start of every winter anyway, because he likes how the furnace runs better after the maintenance. Both are reasonable, and the office is happy to talk through which fits your house.
Between visits, the one job that is yours is the filter. A filter left too long is an easy thing to fix and an easy thing to forget. If a duct run has gone cold, a room feels stuffy or the furnace has started to smell, call before the season rather than during it.
If a cleaning turns up something bigger, such as an old furnace past repairing, the same office handles replacements and installs, so the cleaning visit and the bigger decision can happen with the same people.
“They cleaned the ducts thoroughly and even cleaned the dirt from the window they put the vacuum through.” Marichele C., Yelp review, September 2019.
The tag, the truck and the number
Both frames below are from Theisen’s own archive. The phone digits on the tag and on the truck door end in 4787, the same four digits the shop answers today at (509) 452-4787. On a rotary dial GL is 45, so GL 2-4787 reads 452-4787. For what Theisen does now, see heating, air conditioning and the full services list, look at recent work in the project showcase, or book a cleaning with the office.
