Answer from Camco
just to put some closure to this, here's what I got from Camco the other day about the anti-freeze:
Hi Mr. Webster,
The antifreeze will be in a solid state at about 8 to 10 degrees. However, it does not expand or burst until -50. Thank you.
Camco Manufacturing Inc.
121 Landmark Dr. Greensboro, NC 27409
Tel: 800.334.2004 Ext. 133 | Fax: 336.668.2049
eMail | www | facebook | YouTube
Also, the label says it is not to be diluted with water.