I am having a new Amana sealed combustion furnace istalled in my home in Minnesota this fall.
Although he says he is willing do it either way, my heating contractor suggested that he let the cold air intake "dump" on the floor next to the water heater and furnace rather than connect it directly to the furnace combustion chamber. He reasons that this allows the very cold winter air to mingle a bit with warmer indoor air before it enters the combustion chamber so it will be easier on the furnace components.
Does this make sense?
Have the combustion air for the amana piped right to the amana.
Provide a combustion air intake for the water heater. Double trap it, then let it dump by the water heater.
Your contractor's suggestion as long as the single combustion air intake is large enough for both the water heater and the furnace is valid as well. Better to have the furnace's air ducted right to it.
If your old furnace had a pilot light you may notice a rise in humidity with the new furnace unless your ventilation system is upgraded as well
The way we build has a greater impact on our comfort, energy consumption and IAQ than any HVAC system we install.
cold supply air
This is a good question to ask, but if you trust him to install it then you should trust he knows what he is doing.
In order for the system to be set up run smooth and efficient you need consistency, to get that you want to keep the variables the same or as near as possible. Having the air as near to room temperature may help with that. Drastic Changing air temps will not.
Every system will not be set up the same unless every home is a duplicate and the climate the same. The installer will be best to assist with these decisions because he can see how the elements will affect your new system. Ask for that efficiency test and let us know how you made out.
Congratulations you will be saving on fuel
Get them to put the PVC onto the furnace.. The furnace is going to last longer getting fresh outside air..
Our cold minnesota winter will not hurt the system at all.
No need to burn the what not that is in the air of your home, and may shorten the life of your heat exchanger..
As for fresh air by the water heater, have a "U" put in to trap/slow down the cold air.
She gonna get cold tonight in MN, 7 degrees!
Yeah. The manufactor designed the furnace to be installed a certian way, but you know, they really don't know what they are doing. You don't really need to follow installation instructions. The are only a suggestion as to proper installation for safe operation.
If anyone else had input on this topic would be much appreciated. I just had my annual inspection and inquired about this for a different reason: upon startup the furnace is farily noisey (right after the thermostat calls for heat and before the blower starts). I was told that direct venting it would isolate the burner noise into the pvc and would likely cut down on the noise. Could anyome comment on this?
Also what advantage(s) are their to having sealed air combustion....I keep getting different opnions. Iam in MN as well
[Edited by he8833 on 11-20-2005 at 12:35 AM]
Well, here's the way I explain it when I have to. There's NO down side to running the furnace with the intake pipe connected... like the manufactor wants it.
There are however MANY down sides to running it with out the intake pipe hooked up.
Seems to be enough to sway my choice.
And yes, hooking up the intake should quiet it down some.
So could we here about some of the upsides.
If I were to follow the manufactures directions is this something a homeowner who WOULD PULL A PERMIT be capable of doing? I assume you are simply connecting it to the furance and then following all manfucatres instrcuting for elbows, PVC size, relation to windows doors gas meters etc.
Burner noise will not be affected by connecting the "fresh air" pipe to the furnace. What make and model do you have? Are there any louvers on the doors? If not then you may see some reduction in noise by connecting the intake air pipe directly to the furnace. If at all possible the units should be running 2 pipe setup instead of vent pipe solely connected. As mentioned there are no drawbacks to doing this but several to not doing it.
"Go big or Go Home"
I have a GMNT 0804 Goodman apprx 3-4 yrs old and came with the house when we bought it so I Iam unable to comment on the installation and opinion of the installation which I guessing is suspect as the noise in my opnion is not acceptable. I get the vibartion/noise right after the thermostat calls for heat and u can clearly hear it before the blower starts. Once that happens it seems to dispate but I believe it simply gets drowned out by the blower pushing the air threw the supplies. It does sit on pads on each corner and does have flexibel collar on both the rtn and supply coming off the furnace. (Maybe the ductwork directly above the unit is to tight) and pressed up against the joist?) The furance sits directly above our living room where the kids usually play and where TV is. And quite frankly where its most noticeable. When your in the furance room its not as distinct as when your on the 1st floor above it? Any suggestinons I can suggest to a tech to look at
Their are two panels on the front of the unit
As for 2 pipe Iam assuming that simply means when the furnance is considered "dual pipe" or 2 pipe when its 1# have your PVC exhausting which in my case is through the siding vs up the chimmney and #2 have your combustion air "sealed" directly directly into the unit.
Would I simply then leave my black flexible intake which terminates bewteen my hot water geater and furnace as is?
Bad combustion at start up may be creating that initial sound, as the box receives heat the air moves air up the stack and no more sound. This could be caused by several things. Cold air in the chamber during start up could be one of them. Do the test and see how you have been set up, if you do not already have that tag hanging on the furnace it was set up visually and that will not tell you how the duct or combustion are working. This is why I say the person installing it and having to respond to it at the middle of the night in the freezing cold will know best how he thinks it should be set up.
Have you again asked the installer about direct outside air? Fill us in on his responds?