How should a high-efficiency furnace be vented?

A two pipe venting system should be installed that provides combustion air to the furnace directly from outside. Acidic condensate should be drained or pumped directly into the plumbing system.

How far can you vent high-efficiency furnace?

The maximum vertical distance you can run a furnace exhaust vent is about 15 feet. If there is a forced air inlet within 10 feet of the exhaust vent, the exhaust gas ventilation terminal should be positioned at least 3 feet above it.

Should I go with a high-efficiency furnace?

The greatest advantage of high-efficiency furnaces is that they can save you quite a lot on your energy bill. Heating and cooling typically account for more than half of the energy used in your home. A more efficient furnace can definitely make a difference.

How does a 96% efficiency furnace work?

However, a high-efficiency furnace has a second heat exchanger. The second heat exchanger absorbs heat from exhaust gases and reuses that heat to warm your home’s air. Because the second heat exchanger essentially recycles heat, making the 96% furnace much more energy efficient.

How do you vent a furnace through the roof?

Quote from the video:
Quote from Youtube video: If I follow the line straight up from the outlet of the furnace. I can follow it up and luckily enough there's a sheetrock tape line that just about lines up with where the chimney needs to go.

What type of venting does a high efficiency furnace use?

sidewall vents

High-efficiency furnaces use sidewall vents for “breathing” in outside air for fuel combustion, and “exhaling” cooled exhaust gases nearly depleted of heat.

How many elbows can a furnace vent have?

two elbows

The design tables for flue sizing assume the flue will have two elbows. If there are more, this could be a possible red flag. Flues can have more than two elbows, but this should be taken into consideration in the design stage.

Does a high efficiency furnace need a chimney?

That’s because high-efficiency systems don’t need a flue or smokestack for exhaust. Instead, they use PVC piping. The piping runs horizontally and out of the home through a wall. With a high-efficiency gas furnace, then, our homeowner didn’t need his chimney.

Can a furnace vent pipe have an elbow?

Bend It. A direct vent stove can have an elbow in the vent, and those vented through a wall instead of the roof often do. This is because it is recommended that the pipe run vertically for a certain distance before reaching the outside. In these cases the elbow may be either inside or inside the wall.

Why do high efficiency furnaces drain water?

The purpose of the second heat exchanger is to get more heat from the exhaust before it is vented. As a result, high-efficiency furnaces require condensate drains because their exhaust gases cool enough to allow the moisture in them to condense from steam into water droplets.

Which is better 80 or 96 furnace?

We are often asked what the differences in 80% and 96% efficient furnaces are. Obviously, the 96% efficient furnace will be more efficient using natural gas to heat your home. In fact, it is 16% more efficient. Both types of furnaces have single-stage or two-stage heating models.

Do high efficiency furnaces produce condensate?

High-Efficiency Furnaces Produce Lots of Condensation



As the exhaust product cools, it produces condensation. High-efficiency furnaces extract as much heat from their exhaust products as possible, so the exhaust products in high-efficiency furnaces produce lots of condensation.

Do high efficiency furnaces leak water?

This condensation means that high-efficiency furnaces need a way to drain the water away from the system. This is accomplished through the use of a drain line, drain pan and floor drain. Any clogs, leaks or damage in these components can lead to water leaking out of the furnace instead of draining away as it should.

Where should furnace condensate drain?

The condensate drains out through a pipe, usually on the bottom of the furnace. Most high-efficiency furnaces also have a secondary drain line that comes out of the flue pipe. This secondary line is used to drain any residual moisture so it doesn’t leak into your furnace.

Does a furnace condensate drain need a trap?

All condensate drains go into a trap. The condensate trap is absolutely mandatory for a high-efficiency gas furnace. Since the drain taps into the exhaust system, leaving it open to the air would allow for a potential exhaust/flue gas leak in the living space, which is a big no-no.

Does a furnace need a drain pan?

The condensate drain pan is an important part of the entire central air system. This little tray protects your home from damage and protects the furnace from microbiological growth and failure. Perhaps most importantly, it protects your home from any type of water-related safety issues.

Why do high efficiency furnaces use PVC?

This combination of carbon dioxide and water would damage the type of vents used in conventional systems which run vertically out of a home. To combat this issue, high efficiency condensing furnace uses PVC pipes to extract the acidic water from your home.

How many roll outs can a furnace have?

Oftentimes, there will be two or even three flame rollout switches in the furnace. For example, some furnaces have a rollout switch on each side of the burner compartment.

What is an open rollout on a furnace?

A roll-out switch is a safety device that monitors the flames inside a gas furnace. If the flames creep back into the unit, the roll-out switch shuts down the gas to avoid overheating, exhaust buildup, and other issues.

What is a flame roll-out?

What Is Flame Rollout? Flame rollout is when flames rollout of the combustion chamber of your furnace. Rollout is caused by the combination of gases and flames present when the furnace is in operation. When the furnace is on, flames ignite and are meant to remain inside the combustion chamber.