Heating, Air Conditioning, Fridge, HVAC/Evcon 7975-375 Thermostat

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QUESTION: Hello, I have an Evcon 7975-375 Thermostat that intermittently fails to send commands to the Williams furnace in our ooooold old house. The electrician that comes out says we just have to "put this up" on the thermostat but didn't exactly show me to what he was referring. I moved the only thing up inside the thermostat that I could find, which was a little brass piece from 2 to 5 but it didn't do anything. Any help would be appreciated.

ANSWER: Hi Carolyn, I can't seem to find much on that stat. Is there any way to send me a picture of the stat that shows the brass piece? Is this a heat only stat?

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thermostat
thermostat  
QUESTION: Ah, I got the numbers on the brass piece wrong. I moved it from .5 to .2, and now it's at .4; I got it to work, but I don't understand why it has to be at .2 for us to be able to change the temperature? It'd be nice if I could find the manual! Alas, the owner doesn't know where it is, and as a measley renter, I'm not powerful enough to demand it. I hope the picture helps?

Answer
Carolyn, Now the numbers make since. Thats called a heat anticipator. Basically it adjusts the sensitivity of the stat. .5 being less sensitive. That would prevent any short cycling of the of the furnace. I would see if the landlord would get you a new stat ( good luck with that). It looks like that one is 15 years old. I could help you with installing the new stat.

Let me know what happens.

Heating, Air Conditioning, Fridge, HVAC

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Jim S.

Expertise

I can answer questions on gas or electric furnaces, ac units and heat pumps. I don't work on boilers,chillers,or home appliances.

Experience

I have been in the HVAC trade for over 35 years. For the past 15 years I have owned my own business. I am semi-retired so I can answer questions in a timely manner.

Education/Credentials
I attended trade school for 5 years on weekends and evenings. This was very hard to do, but well worth it!

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