I understand your DIY issues. But for the record, I have been in the plumbing/water conditioning industry since 1977. I am a Level 6 Water Specialist covering point of use/point of entry applications, reverse osmosis and ultrafiltration, demineralization through ion exchange, filtration, disinfection, and ozonation. I have constructed three complete bottled water plants from the ground, up and received NSF certification in each, handled high purity water treatment for many hospitals/medical facilities, done countless commercial/industrial applications. I have done lots of consultation work and system design for the DEC and EPA regarding ground water remediation of volitile organics and carcinogens. I have installed many pumping systems, both commercial/residential, complete plumbing, drainage and septic systems, as well as hot water boiler systems. It's rare that I work with boiler aquastats. I've installed them when doing systems but don't really get involved in servicing them. I just know the one I'm referring to is bad. All I was trying to do is get information from someone who does on a constant basis, so I could be sure I got the correct part.