hoping for some advice out there. I have the captioned unit on a home I just bought. As would be the case [], the heater is now acting up and it is also long out of warranty. There is a digital display that does not consistently respond to my 'commands'. is it fair to say that the 'control module' is gone and I need to replace it? I am fairly handy and it appears that I could remove the top grate of the unit to access the control module and swap it out? might I be lucky and a new control module [around $450] not be the problem?? thanks folks!