Q. We have a window with a purplish-tint film that we would like to remove. It is in a Florida condo, so it has been exposed to a lot of heat and sun and appears to be pretty old. What is the best way to do this without damaging the glass?
A. I reached out to my friend Steve Franson at Window Film Depot. Steve and I have worked together on projects installing UV film and other special coverings to protect glass in danger areas — a less expensive alternative to tempered glass.
Steve advises the following method:
1. Start by heating the filmed surface with a hair dryer (a heat gun would be too hot).
2. Lift the film at a corner with your fingernail or a straight-edge razor.
3. With the hair dryer still heating the film, pull it away from the glass surface. If the film has aged, it may come off in small strips.
4. The stripped film will leave an adhesive residue. Fill a quart bottle with a spray nozzle with water and add a teaspoon of baby shampoo.
5. Protect the surrounding area with a dropcloth. Spray the glass and let it sit for a minute.
6. Spray it again and, using a straight-edge razor, begin scraping off the residue.
7. Keep the surface wet to avoid scratching the glass.
Q. Are high-efficiency modulating condensing propane-fired boilers safe, reliable, and suitable for use with a three-zone hot-water baseboard heating system in a location with high winds between the ocean and a marsh?
We are thinking of replacing ours (which has failed many times) with a conventional propane boiler with mechanical venting. We had replaced our conventional boiler with a high-efficiency modulating condensing boiler in October 2009. A year later the boiler failed due to significant internal corrosion. The installer and factory representative checked the system, replaced parts, and made changes to the venting and air-intake systems. Between 2010 and January 2013, the boiler failed many times, so we had a new boiler (same as the original model) installed. In January 2013, that replacement boiler experienced significant corrosion and stopped operating, so we had a third modulating condensing boiler (a different model) installed. This third boiler failed in December 2015 due to significant corrosion. We had parts replaced and the air-intake and venting system modified.
To date no one has given us a reason for the boiler failures. We heard recently that modulating condensing boilers do not deliver the stated efficiency when used with hot water baseboard heating and that a conventional boiler would be best, especially in this location.
Our original conventional propane boiler lasted 18 years.
We are thinking of returning to a conventional propane boiler. What are your thoughts on the subject?
PAUL IVASKA, Newbury
A. According to my brother, a plumber, modulating condensing boilers perform as well and safely as natural gas. Like anything, they need to be properly installed and maintained. High wind, however, can cause problems with the direct vent equipment. Try relocating it or installing a natural (evergreen) or man-made wind screen. Ensure that you follow code for proper clearances.