As another storm races up the East Coast threatening to dump a foot or more of snow, owners of new homes or retrofitted high-efficiency natural gas furnaces should know this tip.
Your natural gas furnace may vent to the side of your house, and it may also intake air from the side of your home.
Winds in a blizzard can cause light flaky snow to blow up against your exterior walls building snowdrifts that cover these critical furnace pipes.
If the intake or exhaust pipes get covered with snow then your system will shut down ~ and that may be your heating issue.
So, note where the pipes exit your home and go outside to make sure they are completely clear of snow or debris.
Last winter this exact situation happened to one of my clients who had bought a new home in Vienna, Virginia.
In his situation, fast blowing snow had built up over the air intake pipe which was located about two feet off the ground at his house.
The built-in safety switch worked well, shutting off the furnace on one of the coldest days of the year,
After spending an hour flipping switches and checking circuit breakers, he ventured outside to discover a snowdrift covering the fresh-air intake pipe to his furnace. These high-efficiency systems pull in the fresh air, and then exhaust the combustion fumes out a secondary pipe.
Most new homes have two heating systems, one for the basement and main level, and one for the bedroom level(s). The lower-level heating systems are the ones most prone to shut down by snowdrifts.
New natural gas furnaces are extremely energy efficient and work differently than older-style gas furnaces.
- First, they don’t require a metal chimney as the exhaust is cool enough to be carried through special PVC pipes.
- Second, they draw fresh air through an intake pipe into the combustion chamber rather than use the air from inside your home.
If you don’t have heat, check the side of your house!
The HVAC system will sense when airflow isn’t correct
and shut down to prevent a carbon monoxide problem.
New home construction, especially here in Vienna Virginia, seems to be focused on making homes super energy-efficient. One technique is using advanced insulation products like spray foam insulation, known as Icynene, which is commonly sprayed where floor joists meet exterior walls.
Icynene is sprayed into these joints where the Icynene expands before it hardens in place creating a very solid barrier that allows virtually no airflow.
Pulling in the combustion air and exhausting the fumes makes for a very efficient system.