New rth2410 installed. heat won't work but cool does

What type of system do you have?
If you have a heat pump with a reversing valve you will need to set the thermostat settings for a heat pump. Or it can also be the wiring. Check your setting on the thermostat.

press and hold up and down arrows until screen changes. Function 1 should be changed FROM 0 to 1

Your system has 2 stages of heat. Therefore you should have a 2 stage tstat. The 2510 is 1heat/1cool, put your w2 wire in with your w1 wire, you will be fine.

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Go into the programing and change the reversing valve setting to the next number.

After I have been reading up on your unit it appears that the thermostat is not operating correctly. I found this real basic information on installation for your unit. This link I am giving is pretty basic instal schematics. But seems to be something about your thermostat needs to be dialed in or is not working properly.

http://www.premsales.net/docs/GE/GE%20Minisplits.pdf

I hope this helps some. Mike

sounds like you have 24 v going to the g terminal check that otherwise the fan relay in the furnace is stuck closed or the thermostat is defective

Auxiliary heat is electric heat that is put into the air handler on the inside of the house. Its used when your heat pump doesn't provide enough heat, but heat strips are not always used. To see if you have auxiliary heat, look inside and see if you have breakers on the front panel of the air handler or anywhere close. No breakers, no electric heat. Hope this helps!

What was the old thermostat labels and the wire colors that went to them?
The typical heatpump wiring Terminals are:
R = Red = Hot side of Transformer
C-B-X = Common side of transformer Depending on brand of heatpump
Y = Yellow = Cooling Contactor
G = Green = Furnace Blower
O = Orange Reversing Valve Energize to Cool
B = Blue Reversing Energise to Heat Depending on brand of heatpump.
W2 = White = Auxiliary Heat
You need to be sure where each wire comes from when you connect them to the new thermostat.
The best way to do that is to go to the furnace and see where they are connected. R-Y-G are probably correct, you need to see where the Blue wire comes from and determine what the X terminal was on the old thermostat.

Mine just broke too - it won't heat - everything else works - lights, timer ect. but no heat can't cook
without it - love my oven - any solutions ( I guess it's the heating element ) Hope I can get a new one.