Forced Hot Air Furnaces : Troubleshooting and Repair


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Forced Air Heater Solar PART 1 Passive Heating Recycled Glass Soda Pop Can Free

This is a clear alternative to the soda pop can solar furnace. Simply placing a black backer behind glass with a very thin air gap allows for ...


Venting high efficiency forced air furnaces?

Oct 18, 2006 by bubba | Posted in Maintenance & Repairs

I've review that when venting a high efficiency condensing furnace that you can vent directly outside using PVC, but do you HAVE TO? I would espouse to vent to my existing flue, but if I can't, must I reduce the diameter of my flue since only the water heater will be venting to it?

90%+ expertness furnaces all vent to the outside utilizing PVC pipe. Venting may be done through an existing flue but ONLY if PVC is used from the furnace to the ceasing and ONLY if there is no other vent in the flue that is not PVC. You may vent through the rim joist, wall, or roof with PVC provided that you meet all of the manufacturer's specifications. Yes, you must abridge the flue diameter if it is oversize according to the venting tables. This is normally accomplished by installed a pliant, aluminum chimney liner. There is an alternative. You may install a direct-vent water heater that can be vented with PVC. The only flaw to doing so is that direct-vent water heaters are more expensive to purchase and more expensive to install. What it all boils down to is that codes say goodbye you with very few options. Good luck.

Huero | Oct 18, 2006

Not a wholesome idea to vent high efficiency furnace into chimney. If you vent it into chimney flue gas will condensate and destruction the chimney also you will need liner for the water heater.
bob r | Oct 18, 2006

You have to reinforce the gas code to the letter as the inspector will red tag you if not vented properly, besides the condensate will rot your existing metal flue and will make allowance carbon monoxide into the residence and you will not wake up some morning. Do it correctly as there are no shortcuts with your safety and your families lives are at lash too. PS: for true high efficiency you have a return air pipe that supplies air to furnace to use outside air for combustion. check out it and please do it properly.
colinhughes333 | Oct 18, 2006

90%+ experience furnaces all vent to the outside utilizing PVC pipe. Venting may be done through an existing flue but ONLY if PVC is used from the furnace to the end and ONLY if there is no other vent in the flue that is not PVC. You may vent through the rim joist, wall, or roof with PVC provided that you meet all of the manufacturer's specifications. Yes, you must crop the flue diameter if it is oversize according to the venting tables. This is normally accomplished by installed a pliant, aluminum chimney liner. There is an alternative. You may install a direct-vent water heater that can be vented with PVC. The only handicap to doing so is that direct-vent water heaters are more expensive to purchase and more expensive to install. What it all boils down to is that codes off you with very few options. Good luck.
Huero | Oct 18, 2006

A condensing standard of furnace extracts so much heat from the exhaust gases that it reduces the temperature of the gas to the point where water vapor turns to solvent and acids (eg sulphuric and nitric) form in the condensate. A stainless steel flue will corrode or a masonry flue will become marred, allowing holes to form and exhaust gas to leak into your house. A PVC flue will not corrode or pit.

You also stress a separate condensate drain line, typically 1" or 3/4" PVC sprinkler shush up to allow the acidic water to drain into the ground. Some building codes require a dry sump for the condensate. A dry sump is a 24"x24"x18" strong the ocean hole filled with rocks and gravel, then covered with about 4" of dirt.
Tom-SJ | Oct 18, 2006

What do I need to add to a 2.5 ton air condensor being installed with a kerosene forced air unit?

Jun 01, 2007 by MARY C | Posted in Do It Yourself (DIY)

I have a new 2.5 ton condensor to connect central air, but do not know what type air handler to get to work with the present kerosene forced air furnace.

Call a contractor.

stevies49ers | Jun 01, 2007

Venting a high efficiency forced air furnace?

Oct 23, 2006 by bubba | Posted in Maintenance & Repairs

I recently purchased a strong efficiency forced air furnace. I understand that I cannot vent to my existing flue, I must vent directly outside using PVC. What are my limitations for this run? (How long can my run be, must it be a straight run or can I have elbows in it?). Anything else I need to know concerning this issue? Thanks

You don't say how many BTU's we're dealing with so I can only give you a undetailed, rather than a specific, answer. PVC flue pipes are 2" or 3" depending upon the size of the furnace and the industrialist's specifications. It would probably be safe to say that 70 ft maximum with no more than five 90-degree elbows would be O.K. Additionally, the meerschaum must be pitched so that moisture within the pipe will run back toward the furnace. A pitch of 1/4" per foot should be sufficient. So, to sum it all up, try 3" hush up with long-radius elbows and support it every 4 horizontal ft. Good luck.

Huero | Oct 23, 2006

Forced Air Furnaces - News


Condensation could mean humidity is high The Detroit News
- Mar 25, 2009
Condensation could indicate humidity is highThe Detroit News, MIDear Dan: It sounds to me like you have lack of combustion air and too much humidity. New windows have stopped the air leaks. Settle a Skuttle, (888) 758-8853, www.skuttle.com, model 216 for forced air systems or the Skuttle Diffuser for boiler

Control humidity for more efficient energy use Newsday
- Mar 05, 2009
Management humidity for more efficient energy useNewsday, NYMost residential homes are heated by either a boiler and radiator system or by an oil- or gas-fired, forced-air furnace. To add humidity with a forced-air furnace, a humidifier is installed on the come up with side of the ductwork.