"Hassler replaced our entire house heating system and was one of the best companies we have ever hired for anything. Just great and so considerate and professional. Every contact was excellent, each employee was helpful and informative. They are true problem "solvers". We installed an extra air filter , the IQAir medical grade filter. The air is so fresh now. Mike, the owner came over and made an excellent plan with four thermostat control zones. Andy was a fantastic team leader for the installation aided by Cesar, Abraham and Alberto. Keith and Tanzeel did a careful environment assessment report for our rebates. The office staff too...so nice (Eddie, Ramon, Jen). Thanks to all including Trevor who made an extra effort on our last day with a few details. What a great team. Organized and efficient. We would highly recommend them."