How to get UI to update with setpoint

I have a 3m-50 filtrete thermostat that I got rigged up with OpenHab. I can get temp, change mode, and set temp but it’s a little buggy. Whenever I change the temperature, it’ll actually send the command to the thermostat but it doesn’t reflect the new set temp in the UI unless I refresh the screen. So in order to increase the temperature from 68-71, i have to hit the up arrow, refresh, hit the up arrow, refresh, then hit the up arrow again. How do I force openhab to update the UI to the new setpoint temp with each button press?

This is my item file:
Number Thermostat_Cool_SP "Cool Setpoint [%.1f F]" <temperature> (Thermostat) {http="<[tstat:60000:JSONPATH($.t_cool)]"}

My sitemap:
Setpoint item=Thermostat_Cool_SP label="Cool Set Point [%.1f F]" icon="temperature" step=1

And my rules:
rule "Set Cool SetPoint" when Item Thermostat_Cool_SP received command then output = sendHttpPostRequest("http://192.168.29.189/tstat", "application/json", '{"tmode":2,"t_cool":' + receivedCommand + '}') logInfo("HVAC","HVAC Command sent - output: "+output) end

This sounds like the same much reported bug I and others have seen. There is a problem with how the communication between OH1’s server and UI works such that the UI doesn’t always get updates. The fix is extensive (requiring the replacement of a framework that is used all over the place) so a fix for OH1 will not be made. OH2 uses a different framework so this error should not be a problem in OH2.