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Is heating system to blame for mold?
The heating system in our rental is single pipe steam heat. Whenever the system runs, we hear the hissing and sometimes see steam coming out of the radiators. First night...it woke us up, but we got used to it. Each radiator has a dial/valve thing you can adjust although some of them do not adjust anymore and are stuck in position.
We have mold growing on every windowsill and condensation on all exterior walls that cause mold to grow. Every window in the house is half covered in condensation and water pools on the baseboard in some places.
The relative humidity in the house ranges from 50-60% most of the time. This is an older house/duplex probaby built in 1920 or so. I doubt the system has been serviced recently.
The landlord had a cleaning crew come and remove the mold--apparantly something they have had to do repeatedly for other tenants in years past. Most windows are replacement vinal windows, but they are still covered in water. I don't know if the walls are insulalted or not.
I'm thinking the heating system is to blame here. I'm hearing it in stereo right now as it hisses constantly while it is on, but I don't know if that is normal or not.
additional data point: after scraping dust off system, I discovered a tag--installed in 1985. No evidence of service tags or indication the system has been "disturbed" since...