Installed Honeywell RTH2510, Fan won't shut off
#1
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I installed the new 7 day programmable RTH2510 by Honeywell in our church, I'm quite sure I got the wiring as per installation guide. However, the fan comes on regardless of temperature and won't shut off, this is in either the Auto or On mode. Any suggestions?
#2
Just make sure the G wire is not shorting out to R next to it.
If you know it's not shorting out, pull the G wire out of the slot and see what happens.
Some furnace will turn on the blower after the power has gone out for few minutes.
If you know it's not shorting out, pull the G wire out of the slot and see what happens.
Some furnace will turn on the blower after the power has gone out for few minutes.
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I'll try that out tonight at the church: the old thermostat configuration had a wire from the furnace connected to the C, RH, Y, W, G posts, nothing on the O/B post and there was a jumper wire running from the RH to the RC posts. So when I wired the new thermostat in I connected nothing to the O/B, Y to Y, Rh to R, G to G, W to W/AUX, C to RC. At least that's what looked right to me.
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Still having the same problem and now no heat: The original wiring to the old thermostat was as follows:
Blue wire to C, Red wire to RH, Yellow wire to Y, White wire to W, Green wire G, nothing on the O/B post and there was a jumper wire running from the RH to the RC posts.
The new thermostat only has 5 posts O/B, Y, R, G and W/AUX. It has two jumpers on the back which I left at their factory settings. I currently have Old Y to New Y, Old R to New R, Old G to New G, and Old W to New W/AUX, the old blue wire that hung on the Old C post is not connected.
Blue wire to C, Red wire to RH, Yellow wire to Y, White wire to W, Green wire G, nothing on the O/B post and there was a jumper wire running from the RH to the RC posts.
The new thermostat only has 5 posts O/B, Y, R, G and W/AUX. It has two jumpers on the back which I left at their factory settings. I currently have Old Y to New Y, Old R to New R, Old G to New G, and Old W to New W/AUX, the old blue wire that hung on the Old C post is not connected.
#6
Having the old C (Commons) wire on Rc (Hot) may have burned out the transformer, or blew a fuse on the unit.
When you switch the fan switch to ON, does the fan run?
Do you have a meter to check for low voltage? Check between R and C at the furnace.
When you switch the fan switch to ON, does the fan run?
Do you have a meter to check for low voltage? Check between R and C at the furnace.
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I'll check the fan and voltage Saturday. I've not switched the fan to ON yet as I wanted to see if it did shut off when the appropriate temp was achieved. I think I'm OK with respect to the fuse or transformer - the furnace has an electronic ignition, and I can see it attempting to fire when I turn the unit on. So I will not rehook the Old C to anything. Do you think the way I currently have it wired (Old Y to New Y, Old R to New R, Old G to New G, and Old W to New W/AUX) is correct?
#8
You got it right, and make sure you still got the jumper inbetween R and Rc at the t-stat.