Glycol coolant

I'm on the hunt for 2 7bbl jacketed fermenters. Which admittedly is a major upgrade. What I'm wondering is if the glycol coolers also heat on demand at the temp I set. Any experience is welcome.

No one that I know of (Carrier, Edwards, Trane, York) are building a combo unit. Your question doesn't include what you are wanting to accomplish, other than heating on demand and cooling. Are you using the tanks to boil, cool, ferment or settle? There are a few ways to do what you're asking. They all depend on your process. One way requires a dual circuit tank. Glycol in the chilling circuit and depending on the heating requirement, steam or hot water in the other circuit. You will need a chiller and a boiler. Another way is to use the jacket for the heat cycle. For the cooling cycle, circulate the wort/beer through a stainless chiller. Still, you will need a boiler and chiller. If you desire to use glycol as the heating and cooling medium in a single circuit tank, be advised, that to cool a hot fluid requires a specialized chiller. To heat a cold fluid requires a boiler that won't be damaged by cold shock. To maintain a one degree product range requires special contol valves and devices that will contol them, in order to prevent the thousands of dollars of equipment that you will need, from ending up in the junk yard. The big boys use a water tower coupled to the chiller. The water tower pulls down the initial heat load to where the chiller can handle the load without getting damaged. During the cooler months, it takes over for the chiller. On the boiler side a converter is used. The converter allows the boiler to be kept at a constant temp, by using a two direction modulating valve. The fluid used for heating during the process passes through the secondary circuit inside of the converter.

Thank you for the in-depth reply. I should have included more detail in my initial post.
I bought a 3bbl brew house to supply high quality beer to guests of my vacation rental as well as other local lodges.
I live in SE Alaska where outside temps range from the 30's in the winter to 70's in the summer, with most of the temps averaging in the 50's.
I'll start out with 2 7bbl fermenters and a brite tank with final packaging into 1/6bbl kegs and the odd growler.
My worry was keeping my fermentation temps under control since I wasn't planning on heating the brewery itself, but doing some fashion of if environmental control in the fermentation room. Since it's a small operation, I'm guessing a good space heater will work just fine.
When it comes time to crash the brite tank is the same glycol cooler used to control that as well?