I found SumZero on the Bosch recommended installers for my area. They turned out to be everything I hoped to find in a company to have my HVAC system upgraded from an old oil furnace to a hybrid heat pump/oil system. I worked with Paul, on the sales side and he was extremely responsive and never pushy. Paul also actively worked on figuring out the newly changed rules around Mass Save rebate program (no other company I contacted did this). Finally the quote was competitive, the delivery was extremely quick and on time, I was never left without heating and the crew that came for the install (Franco, Daniel and Marcelo) was a pleasure to have around. Finally SumZero really shined also post-installation with an incredible 1hr response time to have a team over to check on a small issue. They definitely earned my trust and my business, great job!
