Weil-McLain Canada has launched a new series of high efficiency gas boilers. The GV90+ cast iron boiler achieves up to 92 percent AFUE efficiency thanks to a durable cast iron primary heat exchanger with a unique seven-pass design along with a stainless steel condensing secondary heat exchanger. In retrofit applications, extra wide waterways allow sludge typically present in older systems to flow through easily. A built-in dual circulator strategy allows low temperature return water. Electronic controls are straightforward with flashing LED diagnostics. The GV90+ offers multiple PVC venting options and is available in sizes from 70,000 to 175,000 Btu/h.