Hi, I am looking to replace a Lux PSP511 with a Ventstar Wireless Thermostat system (SKU HA-30403). It is a two wire system controlling a gas boiler. The wires go to the W and RH terminals on the Lux (it looks like the RH is also bridged to the RC terminal). Can I simply replace the Lux with the Ventstar reciever, or do I need additional equipment since I only have two wires?
Yes you need additional equipment to enable this wireless receiver to work with a 2-wire system. Check out p9 of the receiver install manual here: http://www.rfwel.com/kc/pdf/T1100REC...nstallRev3.pdf
From the picture you can see that you need to get a 24VAC SPST normally-open relay (SPST = single pole single throw) which is simply an electronic switch under the control of the "W1,O,B " terminals. So when the receiver is calling for Heat "W1" is 24VAC, "C" is ground, and "R/W" on your wall is closed.
We might actually have those kits in stock but i don't see them on our e-store but I will have them add them and update this post with where you can pick them up. You could also always call/email us to get them or visit your local h/w store. One caveat though which should go without saying is that if you have any doubt with any of this stuff please consult a qualified HVAC technician.
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