Called Horizon for yearly furnace checkup. Furnace is 13 years old and working fine. Told us we had a "blocked" heater exchange, causing large amounts of carbon monoxide to go up the chimney. Told us that, by law, he had to turn off the furnace until it was corrected. New heater exchange would cost over $5000. Sales rep came next day to discuss replacement. 2 options 1. cost over $10,000 2. cost over $11,000. Told the rep that we would get other quotes and he left. Called back in about 2 hours and quoted new "employee" price, both options $6000 range. Had another company come and check furnace, found no cause for concern or repair. Predatory practice on the part of Horizon. Stay away from them. read more