The Laars Mini-Therm gas-fired residential hydronic boiler is an ideal heating appliance that can reduce homeowners heating costs and has plenty of capacity to keep even the largest home comfortable on the coldest days. The compact boiler has a low-mass heat exchanger and a super-quick heating response to meet your residential application requirements. The Mini-Therm JVH uses an H.S.I. (hot surface ignition system) to operate all six sizes in singlestage, on/off firing modes. The boiler is equipped with a draft blower that permits side-wall or chimney venting. Compact models are also easy to install, operate and maintain.