Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > HVAC

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Search this Thread Display Modes
Old 11-25-2008, 08:33 PM   #16
Member
 
Join Date: Nov 2008
Posts: 70
Rewards Points: 0
Share |
Default

Problems with new furnace..Overheating, having to reset. Furnace too big?


Good good good..I think I'm getting somewhere now.
Thanks for pointing me in the right direction.

If the temp rise turns out to be too high..I bet adjusting the speed will take care of it..

I may add another basement duct too...Just for the fun of it. Make sure all warm air is getting expelled.

Edit: looks like the blue wire is actually attached from the factory on this unit (medium high). I kinda doubted it was on a lower setting considering how hard it seems to blow..
So, theres atleast one faster speed I can use if my temp readings indicate too high of a temp rise.


Last edited by Tommy2; 11-25-2008 at 09:03 PM.
Tommy2 is offline   Reply With Quote
Old 11-25-2008, 09:12 PM   #17
Member
 
hvaclover's Avatar
 
Join Date: Oct 2008
Location: Suburbs of Detroit Mi
Posts: 3,704
Rewards Points: 0
Default

Problems with new furnace..Overheating, having to reset. Furnace too big?


Quote:
Originally Posted by Tommy2 View Post
Good good good..I think I'm getting somewhere now.
Thanks for pointing me in the right direction.

If the temp rise turns out to be too high..I bet adjusting the speed will take care of it..

I may add another basement duct too...Just for the fun of it. Make sure all warm air is getting expelled.

Edit: looks like the blue wire is actually attached from the factory on this unit (medium high). I kinda doubted it was on a lower setting considering how hard it seems to blow..
So, theres atleast one faster speed I can use if my temp readings indicate too high of a temp rise.

A jumper comes in the parts bag.Jumper between heat and cool and just use the black wire. It'll operate on high speed in heat and a/c
__________________
Just slow, not stupid.
hvaclover is offline   Reply With Quote
Old 11-25-2008, 09:26 PM   #18
Member
 
Join Date: Nov 2008
Posts: 70
Rewards Points: 0
Default

Problems with new furnace..Overheating, having to reset. Furnace too big?


Yep. I actually dont have AC, so that makes it even simpler, heh.
Thanks
Tommy2 is offline   Reply With Quote
Old 11-26-2008, 02:38 AM   #19
An old Tradesmen
 
Join Date: Oct 2008
Location: PA
Posts: 25,109
Rewards Points: 118
Default

Problems with new furnace..Overheating, having to reset. Furnace too big?


What size was your old furnace.
beenthere is online now   Reply With Quote
Old 11-26-2008, 11:27 AM   #20
Member
 
Join Date: Nov 2008
Posts: 70
Rewards Points: 0
Default

Problems with new furnace..Overheating, having to reset. Furnace too big?


I think it was around 75,000 btu...but I was too stupid to know how to read the tag before I bought my new furnace.
I just asked the counter guy at the furnace supply store what size would be good for 2500 sq ft(just to ballpark it) and he said 100,000 for a high ef.

I think he must have been assuming you need 40 btu for every sq ft. The more research I do, it seems like 30 is a little more accurate. Of course, this is all ball park talk. You have to take into consideration ceiling height, duct work, etc, etc..

Basically..It seems like you'd be better off going a little too small than too big.


I'll also say the furnace hasn't tripped since yesterday..Running plenty too.
Happy about that..

Last edited by Tommy2; 11-26-2008 at 03:36 PM.
Tommy2 is offline   Reply With Quote
Old 11-26-2008, 04:35 PM   #21
An old Tradesmen
 
Join Date: Oct 2008
Location: PA
Posts: 25,109
Rewards Points: 118
Default

Problems with new furnace..Overheating, having to reset. Furnace too big?


Lot of houses work out to 22 to 25 BTU per sq ft.

So, yea, you are grossly oversized.
Most counter guys have no idea how to size a furnace.

You may still be exceeding allowable temp rise.
You might want to add more return and supply to it.
beenthere is online now   Reply With Quote
Old 11-26-2008, 04:51 PM   #22
Member
 
hvaclover's Avatar
 
Join Date: Oct 2008
Location: Suburbs of Detroit Mi
Posts: 3,704
Rewards Points: 0
Default

Problems with new furnace..Overheating, having to reset. Furnace too big?


100k is not "Grossly" over sized Been.
__________________
Just slow, not stupid.
hvaclover is offline   Reply With Quote
Old 11-26-2008, 04:55 PM   #23
An old Tradesmen
 
Join Date: Oct 2008
Location: PA
Posts: 25,109
Rewards Points: 118
Default

Problems with new furnace..Overheating, having to reset. Furnace too big?


Quote:
Originally Posted by hvaclover View Post
100k is not "Grossly" over sized Been.
It is if he only needed a 60,000 BTU.
beenthere is online now   Reply With Quote
Old 11-26-2008, 05:02 PM   #24
Member
 
hvaclover's Avatar
 
Join Date: Oct 2008
Location: Suburbs of Detroit Mi
Posts: 3,704
Rewards Points: 0
Default

Problems with new furnace..Overheating, having to reset. Furnace too big?


Quote:
Originally Posted by beenthere View Post
It is if he only needed a 60,000 BTU.
He said his home was drafty.....uhhhh I assumed he meant badly insulated.

With poor insulation I got 111kbtu.

2500x 40/.90
__________________
Just slow, not stupid.
hvaclover is offline   Reply With Quote
Old 11-26-2008, 05:07 PM   #25
Member
 
Join Date: Nov 2008
Posts: 70
Rewards Points: 0
Default

Problems with new furnace..Overheating, having to reset. Furnace too big?


Yea..I can't possibly imagine 60,000 being big enough - unless the home was super tight.
I live in a 35 y/o home with original single pane windows. Insulation isn't bad(not perfect either)..but the windows are terrible. I'll get around to replacing them eventually..

80,000 probaly would have been just fine.

You live and learn. Cant get a new furnace now..Stuck with making this sucker work for now. I can always add ducts if necessary. Not the end of the world.
I'll make sure to get 80,000 next time(if I still live here). By then I should have new windows, etc, etc..
Tommy2 is offline   Reply With Quote
Old 11-26-2008, 05:11 PM   #26
Member
 
hvaclover's Avatar
 
Join Date: Oct 2008
Location: Suburbs of Detroit Mi
Posts: 3,704
Rewards Points: 0
Default

Problems with new furnace..Overheating, having to reset. Furnace too big?


Quote:
Originally Posted by Tommy2 View Post
Yea..I can't possibly imagine 60,000 being big enough - unless the home was super tight.
I live in a 35 y/o home with original single pane windows. Insulation isn't bad(not perfect either)..but the windows are terrible. I'll get around to replacing them eventually..

80,000 probaly would have been just fine.

You live and learn. Cant get a new furnace now..Stuck with making this sucker work for now. I can always add ducts if necessary. Not the end of the world.
I'll make sure to get 80,000 next time(if I still live here). By then I should have new windows, etc, etc..
Can always resize the orifices.
__________________
Just slow, not stupid.
hvaclover is offline   Reply With Quote
Old 11-26-2008, 05:24 PM   #27
An old Tradesmen
 
Join Date: Oct 2008
Location: PA
Posts: 25,109
Rewards Points: 118
Default

Problems with new furnace..Overheating, having to reset. Furnace too big?


60,000, was just a number I used for example.

If the old furnace was 75,000BTU, and maintained temp.
Then increasing to a 100,000 is grossly oversized.

On your coldest days, did your old furnace have to run continuous, or did it cycle on and off.
beenthere is online now   Reply With Quote
Old 11-26-2008, 06:47 PM   #28
Member
 
Join Date: Nov 2008
Posts: 70
Rewards Points: 0
Default

Problems with new furnace..Overheating, having to reset. Furnace too big?


Quote:
Originally Posted by beenthere View Post
60,000, was just a number I used for example.

If the old furnace was 75,000BTU, and maintained temp.
Then increasing to a 100,000 is grossly oversized.

On your coldest days, did your old furnace have to run continuous, or did it cycle on and off.
Now that I recall..That old furnace would run pretty much continuously when it was single digits..

So a slight step up may not have hurt anything..But I'm not going to argue that 100,000 is probaly too large for my house. But I dont think Im off by too much.

Furnace still cycling fine today. Hmm. not sure what to think of it
Intermittent problems are the worst to solve..but, its working at the moment. So no complaints.

I still want to do the temp reading. Ill try to pick up a thermometor this weekend.
Tommy2 is offline   Reply With Quote
Old 11-26-2008, 07:10 PM   #29
Member
 
hvaclover's Avatar
 
Join Date: Oct 2008
Location: Suburbs of Detroit Mi
Posts: 3,704
Rewards Points: 0
Default

Problems with new furnace..Overheating, having to reset. Furnace too big?


Quote:
Originally Posted by Tommy2 View Post
Now that I recall..That old furnace would run pretty much continuously when it was single digits..

So a slight step up may not have hurt anything..But I'm not going to argue that 100,000 is probaly too large for my house. But I dont think Im off by too much.

Furnace still cycling fine today. Hmm. not sure what to think of it
Intermittent problems are the worst to solve..but, its working at the moment. So no complaints.

I still want to do the temp reading. Ill try to pick up a thermometor this weekend.

This 75kbtu furnace is the second furnace that's been installed since the house was new?
__________________
Just slow, not stupid.
hvaclover is offline   Reply With Quote
Old 11-26-2008, 07:20 PM   #30
Member
 
Join Date: Nov 2008
Posts: 70
Rewards Points: 0
Default

Problems with new furnace..Overheating, having to reset. Furnace too big?


Quote:
Originally Posted by hvaclover View Post
This 75kbtu furnace is the second furnace that's been installed since the house was new?
Probaly. I have no idea on the house's history. Thats the furnace that was there when I moved in 2 years ago. It was from '02.
I sold it..wanted to get rid of the oil stuff. Have an old oil tank. Hate the sootyness of it.

Tommy2 is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
New Cased Coil - Install to Furnace - PICTURES!! hartkem HVAC 39 11-18-2008 01:45 AM
HEIL furnace keeps kicking off reset switch sunsetacres1318 HVAC 8 11-04-2008 08:35 AM
furnace and or electrical problems tuasoi General DIY Discussions 4 11-29-2007 12:50 PM
Furnace Problems? MCSE HVAC 10 12-20-2006 11:06 AM
Furnace Problems? Part 2 MCSE HVAC 9 11-30-2006 09:25 PM




Top of Page | View New Posts

Copyright © 2003-2014 Escalate Media. All Rights Reserved.