ULC ORD C1378

1.1 These requirements apply to factory-built micro Combined Heat and Power (mCHP) gas-fired appliances which are intended primarily for residential and commercial installation. All appliances/equipment are intended to be constructed completely of new, unused parts and materials. 1.2 These appliances are for use with natural gas, liquefied petroleum gases, mixed gas and LP gas-air mixtures. 1.3 On the hot side, heat transfer can be direct from combustion gas to working fluid, or indirect from combustion gas to intermediate fluid. On the cold side, heat transfer will typically be from working fluid to air, water or some other fluid (eg. glycol, brine, oil, etc.). 1.4 The vapour expansion cycle may have indirect heat transfer through an intermediate pressurized water/saturated steam loop between the combustion gas and working fluid. The vapour expansion cycle may have direct heat transfer between the combustion gas and working fluid. Maximum operating conditions of the intermediate fluid shall be 200°C and 1000kPa absolute. Maximum operating conditions of the working fluid shall be 200°C and 2000kPa absolute. 1.5 For the hydronic supply loop of gas-fired boiler-type mCHP appliances, operation is intended according to the following: Hot water heating boiler-type CHP appliances: Up to 1.10 MPa (160 psi) water pressure; 121 °C (250 °F) water temperature. Hot water supply boiler-type CHP appliances: Up to 1.10 MPa (160 psi) water pressure; 121 °C (250 °F) water temperature. The hot water heating boiler-type CHP appliances described herein are intended to produce hot water either by instantaneous or storage means. The hot water heating boiler-type CHP appliances described herein are intended for combination space heating/potable water applications. For the steam supply loop of gas-fired boiler-type mCHP appliances, operation is intended according to the following: 103.42 kPa (15 psi) steam pressure. 1.6 The requirements of Sections 1.4 and 1.5 apply to gas-fired mCHP appliances intended for maximum input rates not exceeding 3,663.389 kW (12,500,000 Btu/hr). 1.7 For vent systems other than direct vent type, flue temperature and vent pressure are considered as either Category III or Category IV, encompassing appliances for either indoor or outdoor installation. This ORD applies, as well, to direct vent type venting systems, also known as balanced flue venting systems, consisting of an air intake and vent termination. 1.8 Power generation capacity of the appliances described herein is intended not to exceed 50kW gross power at the prime mover, before internal power consumption, before any power conversion (i.e. AC or DC). 1.9 Power generation technology types are intended to include vapour expansion cycle (Rankine), Stirling engine, micro-combustion turbine, thermoelectric module, thermoacoustic engine, fuel cell, internal combustion engine and solar photo-voltaic systems. 1.10 These appliances may be provided with construction provisions, or suitable listed kits, to permit conversion from one gas to another. 1.11 A gas-fired mCHP appliance, not specifically identified in the scope of this ORD, may be evaluated as necessary and to the discretion of the certifying agency. 1.12 This ORD encompasses gas-fired mCHP appliances described within that may incorporate grid-tied, micro-grid capability and hybrid (grid-tie / micro-grid combined) capability. 1.13 The intent of this ORD is to cover gas-fired mCHP appliances producing electrical energy by utilizing thermal energy.