Why is the ON/OFF switch on my stove a DPST?

  • Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.
  • Hope everyone has a wonderful and warm Thanksgiving!
  • Super Cedar firestarters 30% discount Use code Hearth2024 Click here

dlstech

Member
Jan 16, 2015
15
OR
Some days/nights I want to keep the stove running a few hours longer when I go to work or sleep but I don't want to leave it on for the whole time. So I bought a spring loaded 6 hour timer to hook up to my stove. I was going to put it in parallel with one of the wires going to the ON/OFF switch so I could set it to however many hours I wanted, flip the stove switch to OFF, and leave it alone.

I got the timer in the mail today and got ready to install it and then saw the stove switch is a DPST. I figured it was just redundancy but nope, if any of the 4 wires are pulled, it turns off. So then I thought they went to different components but both sets go to these electronic timers that are side by side: http://www.primetechnology.com/refr...d=1134&catInfoId=1051&ItemDescription=644A-55

They both seem to be wired up the same way except one has two wires connected to the initiate terminal and one has "off resistance" instead of the "initiate". The + of the input on both of them is bridged together.

Anyways, my question is, why is that a DPST swtich vs a SPST switch? Is it just so they don't have to have 4 wires running into 2 terminals or is there another reason? And will it hurt the stove if I do combine them into one circuit to connect the timer? The DPST model of this timer is $50 and I really don't want to deal with a return and paying that much for a spring loaded timer. Will it hurt anything to use the SPST timer? I can't find a wiring diagram for this stove anywhere. It's an early 90s Avalon 900PS
 
I followed the wires and answered my own question. One wire on the switch is always hot while another one only becomes hot when START is pressed and is connected to the exhaust blower. So I can't connect those together.

Now I still need to figure out if I can someone use this SPST timer on some other part of the stove or if I have to exchange it for the more expensive DPDT timer. Any ideas?
 
maybe use a relay connected to your timer. Timer fires the relay coil, you do what you need with the relay contacts :)
 
The constant power is to run the exhaust blower even if there is a stove problem,such as just turning off the switch,loss of vac,ran out of pellets.A safety thing.But,if you cannot figure it out,let me know and will research