Originally posted by JohnBuckingham We have a 3 ton rooftop AC unit that was left on while the space it serves was demoed. (yeah, we're idiots). Does anyone have any advice on cleaning the coil?
Pull the drain line and cover the return air plenum with plastic sheeting. Use pressure washer and very hot water. Just be careful of damaging the coil fins with too much direct spray or you will only think you are in bad shape now. If you use coil cleaner first you will have the same thing I had in the coil. Concrete
I was wondering if gypsum (drywall) is a base and might dissolve with acid base cleaner? I don't use it but cement dust will disslove with hcl. Just a thought to look into, you would need a lot more info before you try this. and I am not reccomending it.