Service Area Dewitt Grand Ledge Haslett Ionia Lake Odessa Lowell Okemos Portland Sunfield Westphalia Need HVAC Service? Contact the experts at ESI Heating. Call us at 517-647-6906! Request Service ESI Heating proudly provides HVAC service to Portland, Dewitt, Grand Ledge, the Greater Lansing area and the surrounding communities. Visit our service area page for more coverage details, call us at 517-647-6906, or request service online today.