I'm still waiting for my first gift for tirelessly keeping a safe and well-maintained home for my tenants at a very reasonable cost, taking calls at all hours, going out in bad weather, when it's scorching or freezing, and being polite and professional at every interaction, even when I didn't feel like that wasn't reciprocated or appreciated.This is a business. 

What reasons would cause a lender to freeze/call?

Fairly sketchy since I can try to relay a message but no guarantee.My thoughts were 1. to get a bit of oil in the tank to make sure pipes dont freeze and burst 2.

I have never had a fully skirted home freeze while habited by a tenant. 

I had a pipe freeze and break on the top level of my 4 plex, it flooded the attic for 10 hours.

The ice comes from both the snow on the ground, but also as the roof melts, its water falls to the ground and freezes as the temperatures drop at night.

About 90,000 individuals in the Milwaukee, WI area were left without power due to snow storms and below freezing temps.

As for HELOC, things may have changed, but when we used our HELOC, it stated it was for primary residence and they could freeze it if we were no longer owner-occupants. 

However, in the event it takes me 6 months to move on a property, is anyone worried that credit markets tighten or home prices sink enough that banks start to freeze untapped HELOCs?

This has caused some pipes in the basement to freeze and burst.