converting a ranco controller

[fish-freek-3000]

I have a single stage ranco controller for my heaters. no I have come to realize that a single is almost completley useless because the fan and heaters will fight eachother. So now my question. Is there a way to rewire the stock single stage so i can make it a dual stage. thanks. if there is already a thread on this if somebody would point me in the right direction that would be great. tia

[Donw]

Your not going to convert it to dual stage as far as I know anyways. If you open it up you will find no and nc contacts. You can run your fans from the nc contacts so they will turn off when the heat runs.

Don

[fish-freek-3000]

so at one point either one is goin to be running, i c. so if i crack it open i just need to add a plug to those points

[BeanAnimal]

Basically yes. Your heater will be on the NO contacts... when the when they close the heater comes on. If you put the fans on the NC contacts, the fan will run anytime the heater is not running.

The problem is that you will have no hysterisis. That could cause short cycling of the heating and cooling functions. There will be a small lag for evaporative cooling to catch up and this may give you enough hysterisis. You can try it out... but I would venture to say you would be better off with a dual stage unit.

Also of note: You COULD use a simple relay outside of the RANCO to achieve the same type of functionality. McMaster sells DELAY type relays that could be set to delay the turn on of the fan for several minites.

Bean

[fish-freek-3000]

http://www.reefcentral.com/diy/rancosinglewiring.jpg

ok looking at his picture i would just need to put the hot or black wire on the nc point and then wire both white wires, and grounds together

also how does the relay work. is it just inline with the fan. when it gets power it holds it closed for however long i want. tia

[75reef]

What was that song by the "Talking Heads"? Uhm, oh yes..."Burning down the house".
Save your money and buy a dual stage. Ebay sells them rather cheep sometimes.
:strooper:

[BeanAnimal]

Yes the BLACK wire from the FAN would go to the NC terminal. The WHITE wire and GROUND will be tied to the WHITE and GROUND coming from the wall plug.

If you opt to use a relay instead.... The power that comes from the RANCO to the HEATER would go to the RELAY COIL, as well as the heater. The FAN would hook to the relay coils Normaly Closed contacts. Power from the WALL would go to the RELAYS COMMON contact. The neutrals/grounds from the WALL and FAN would be tied together. This is likely NOT a good description... so ask if you plan to use a relay. We can draw you a picture :)