Tankless heat exchanger cleanout.

[clshades]

This is pretty brutal to be honest. Only about 4 years use but the mech room is just off the parking garage and the positive pressure system I setup failed 2 years ago. Told the, then manager, to replace the fan asap, he didn't listen and the dust caused this. This took all day to remove, pull apart and clean. I have 4 more to do. Had the fan been replaced like I asked this never would have been this bad.

Fan cost, 100 bux, if that. Repair, 1000 bux with 4 more boilers to repair. The challenging part is getting all the sensors back in the correct positions or the thing goes up in smoke.

 

[JD]

The fan caused this? I guess this is the hot side of the heat exchanger where the flames hit?

I know most tankless units say to descale them yearly and to clean the water and air filters. I think I have probably missed last year, but it's just one of those things that goes unnoticed... any other tips would be great if you got them!

 

[clshades]

I'll explain better. There's a 20" fresh air intake to supply the mechanical room. I put a fan in front of it to draw more air in and keep the room under positive pressure. The fan failed 2 years ago and wasn't replaced. Because hot always goes to cold, the air then started drawing from the garage pulling dust into the room and causing what you see above.

 

[clshades]

The fan caused this? I guess this is the hot side of the heat exchanger where the flames hit?

I know most tankless units say to descale them yearly and to clean the water and air filters. I think I have probably missed last year, but it's just one of those things that goes unnoticed... any other tips would be great if you got them!

Take a photo of your tankless with the cover off and I can show you how to check the inside of the copper heat exchanger. If yours is running on natural gas it's probably fine.