Outdoor Wood Furnace Info

Outdoor Furnaces - Manufacturers with NON EPA-Certified Models Only => Home Made => Topic started by: brennan81 on April 29, 2014, 01:48:02 PM

Title: Need help with wiring.
Post by: brennan81 on April 29, 2014, 01:48:02 PM
I just joined this forum today, and I've read about every post about building a furnace.  I have a new home that I just finished, and have been heating with a Fisher 2 wood stove.  I want to install radiant floor heating for the first floor and old cast iron radiators for the second floor.  I also want to be able to heat my garage (just to keep it above freezing).  I know how I want to build the furnace, I'm having trouble understanding how to wire it with the aquastat, thermostats, circulating pumps, and blower.  My first Question is do most people have there pump running all the time?  I would like to have a thermostat in the house and the garage.  Then when one would call for heat it would kick on the blower and the circulating pump.  Does this like a good idea?  Or does one pump need to be running all the time to prevent over heating?  I'm starting from scratch with the wiring of the furnace so I can do pretty much do any thing there is now other heating system in the house that will be involved.  Thanks for any advice with the wiring you can give.
Title: Re: Need help with wiring.
Post by: slimjim on April 29, 2014, 02:13:10 PM
I'll try to get back to you this evening.
Title: Re: Need help with wiring.
Post by: LittleJohn on April 29, 2014, 02:54:44 PM
I personally have the pump (between OWB and radiant system FPHE) only come on when there is a call for heat.
However I have a thermostatic bypass valve, so water coming from OWB below 140F gets send back to OWB to get reheated.  This piece of hardware is required with the OWB from Central (I run a eClassic 2400)

Note: Have 2 runs from OWB; 1) 75' one-way to detached garage 2) 100' one way to house
Never have to wait for more than a few minutes (if more than 5 minutes -> I go check to see if OWB is running) before hot water is to FPHE, assuming OWB is up to temp

I also know that my calls for heat will last for an extended perios of time (have in-slab radiant, not fan coil), so pumps runs for a while everytime it turns on. 

**Probably doesn't help u much, but knowledge and examples also help right
Title: Re: Need help with wiring.
Post by: RSI on April 29, 2014, 03:52:06 PM
Keep the outdoor system completely separate from the indoor wiring.

I am assuming you will have forced draft. Just connect the solenoid and fan power together and run the hot wire through the aquastat. (just think of it as a light switch) Really simple.

I would leave the pump running all the time. If the reason you were thinking about having cycles is to save power, you can use two pumps and run one on low speed all the time and have the other come on with demand.
Title: Re: Need help with wiring.
Post by: brennan81 on April 29, 2014, 06:03:10 PM
Thanks for the replies.  I am a moron when it comes to wiring.  I am thinking about having three pumps, one for the radiant floor heat, one for the cast iron radiators, and one for the garage, and then two thermostats one for the garage and one for the house. 
RSI, You said keep the indoor wiring completely separate from the outdoor?  I don't have an indoor system if that is what you meant.
Title: Re: Need help with wiring.
Post by: RSI on April 29, 2014, 06:24:49 PM
I mean keep the owb wire self contained. Just run 120v to it not any controls at the house.
I would run one main pump that runs all the time. The floor pump and radiator pumps should come on with the thermostats.
Title: Re: Need help with wiring.
Post by: brennan81 on April 30, 2014, 02:38:21 AM
I got ya now.  Will I need something special to wire up the two thermostats?
Title: Re: Need help with wiring.
Post by: slimjim on April 30, 2014, 04:14:47 AM
RSI is right, yes you will need a relay from the thermostats because they should be run on 24 volts and not 120, you can purchase a  relay at any supply house or Home Depot, Taco has a good one, be sure to get the circ relay and not the zone valve relay, the wiring instructions are in the box, they are very simple and easy to use.
Title: Re: Need help with wiring.
Post by: brennan81 on April 30, 2014, 03:41:06 PM
Thanks  I looked at the taco relays on line today.  They look pretty simple. 
Title: Re: Need help with wiring.
Post by: RSI on April 30, 2014, 09:48:36 PM
I usually just use a fan center relay. They are fairly cheap and have the transformer and relay together.
Title: Re: Need help with wiring.
Post by: slimjim on May 02, 2014, 06:01:30 AM
I just like the simplicity and ease of wiring on the Taco switching relays, the wiring can be done neatly inside the relay housing, has it's own transformer and indicator lights to show which zones are calling for heat as well as power present at relay indicator, I'm not convinced on the new aerodynamically designed plastic cover though it can be a pain in the, well you know what I mean!