Thermostat upgrade

[eberrobw]

I replaced my furnace thermostat, Atwood Model HFH-2000 with a Hunter Model 42999B. It's a two wire system so I just connected one wire to W and the other to Rh with the jumper installed from Rh to Rc. When I power the airstream (via In Use switch) after having made the new thermostat connections, the furnace fuse blows. I reinstalled the old Atwood thermostat and all works great (except I rather have a digital). Tried to reinstall the new Hunter blowing the fuse again. Any Ideas how I can get it his new Hunter digital thermostat working?


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[drboyd]

The original Atwood thermostats were made to handle the furnace current; your new digital one is probably not. I changed my thermostat and had to add an interposing relay, because it kept burning the contacts in the new stat.

That said, I have no idea why your fuse is blowing, but check for contact where the wires come through the wall.

There's also a toll free number in the manual: http://www.manualguru.com/hunter-fan...-manual/page-2

[eberrobw]

Thanks for the reply. I wired the new 42999b per the 2-wire heat only diagram on page 2 of the document you provided. I'm wondering why I really need (remove) the supplied jumper between Rh and Rc and if I changed the two wire connections to W and Rh? Anyway, I'll call Atwood. Thanks for your help.


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[HowieE]

Reinstall the original thermostat and buy a digital thermometer. Would be better than having to introducing a relay system to allow the new stat to work.

Other than visual display there is nothing the new stat will have to offer.

[markdoane]

Originally Posted by HowieE

Reinstall the original thermostat and buy a digital thermometer. Would be better than having to introducing a relay system to allow the new stat to work.

Other than visual display there is nothing the new stat will have to offer.

Really. I "downgraded" from digitial to analog when the digital failed and I couldn't repair in the field.

[eberrobw]

Thanks all for your help. It's just sort of a challenge for me to figure out how to get this Hunter digital thermostat working. Still messing with it, I'll let you know how I make out.

[KYAirstream]

I installed the same thermostat and didn't have any issues. I just connected the two wires and did not install a jumper. That said, a jumper may have already been in place. I can check the next time I'm at my camper. Also, I'm not sure what difference it would make since this is essentially just a switch supplying juice to the furnace, but my furnace is a Suburban.

[KYAirstream]

Another thought is that maybe there is something wrong with the thermostat itself, thereby causing your fuse to blow.