Mark, I think you’re forgetting about the all-important blower fan in a gas-fired furnace.
That said, the reason the code requires furnaces to be hardwired is to ensure that the blower interlock system can’t be bypassed. An electrical interlock ties a heat recover ventilator to circulation air blower operation of a forced-air furnace system. This ensure that the blower circulates supply and return air within the structure. A plug-in power source leads to the possibility that this interlock could be accidentally defeated, resulting in an overheat within the flame box. -mel > On Aug 31, 2021, at 3:38 AM, Mark Tinka <mark@tinka.africa> wrote: > > > >> On 8/31/21 12:26, Forrest Christian (List Account) wrote: >> >> Yes. Or any other furnace where the electricity is only used for >> circulation of the heat. Gas fired Hot water furnaces would be another >> example where there is minimal electricity used to run the furnace controls >> and circulate the hot water. > > Gas-fired furnaces or heaters should not have an impact because the only > electrical requirement is to fire up the pilot light. > > But fully-electric heating has a much higher impact on energy sources (heat > pumps being the least). > > I believe typical electric central furnaces are anywhere between 10kW - 15kW > systems. Would a standard 4kVA - 8kVA generator for average Jane cut it? Not > sure. > > Then again, I live in a more forgiving climate, so I have a very limited need > to understand this better. > > But I can understand why the code has not caught up to this yet, and insists > on hard-wiring the devices... because the majority of home and buildings will > still be using all-electric equipment that require plenty of energy, where > things can go wrong if you allow Jane to just run her suicide cord any way > she may like. Yes, there may be more folk moving over to other energy sources > that eliminate or reduce the need for electricity, but the code has to cater > for the wider demographic. > > Mark.
