Re: oil fired furnace X-10 off/on swich control

["BruceR" <razrbruce@xxxxxxxxxxxxxxx>]

 Lewis Gardner wrote:
> BruceR wrote:
>> Place one of these in series with the existing switch.
>
> Parallel would work better...

Yes, parallel would work - but no better and, for safety reasons I think
I'd stick with series which would require both switches to be on to
operate. That way, as mentioned in another responder's post, turning off
the original switch for service would positively shut down the furnace
so that service personal could work safely. If wired parallel, the main
switch could be off but if the UM-506 turned on while the service tech
was performing service, the tech could be seriously burned or injured by
the blower fan.  I know I wouldn't want to count on others in my
family - or even myself - to remember the schedule and override it when
being serviced.  I'd hate to see my service guy hauled away in an
ambulance with severe burns or other injuries because of a poor wiring
choice.  Also, while I'm no expert on HVAC codes, I suspect that the
parallel wiring might not meet code for the safety reasons described
above.