New gas furnace time

1,900 sq ft split level CBS ranch, circa 1964, with a flaky natural gas furnace, in the temperate Portland (OR) Metro Area.
Time to replace it. Currently, have a Lennox Conservator III G16, Model: G1603/4-100-3, Input: 100,000 BTU/Hr, Air rise: 35-65 F, and ducting to match. Only have 5,000 sq ft of lot, and drilling is not practical, so practicality of a ground source heat pump doesn't seem to be there.
If you have recently replaced your furnace, would appreciate hearing how you did it and what you learned.
Thank you kindly in advance for your on-topic remarks. Sales droids will be spaced, out the airlock, ga-WOOSH!
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Think natural gas ...not electric/heat pump.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

This is Turtle.
Hey Dave, you need to read better and see he said the ground source heat pump was out of the picture because of area of yard.
TURTLE
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Dave you can't think so why even try?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

This is Turtle
Hey try you a new one but maybe in a Condensing 93% AFUE rating gas furnace this time. The 93% AFUE now days will burn about 30+% less gas than your old one.
TURTLE
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

This is Turtle.
Your talking to a HVAC or Furnace installer and service company owner. i install and service the furnaces your speaking about. I have been doing this type work for the last 40+ years.
I really don't know too much about going through it but I install them for a living.
The Data You give here just seems out of line in the cost savings verses the 80% AFUE to the 94% AFUE. Now I have learned to not argue with a computor set program if it was true in it data output. I will go back tomorrow morning and read it again to see a second look at it.
TURTLE
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Easiest would be to stuff in a 90+ furnace, but I wonder if a DX heat pump would not be a better choice, depending on your electric rates compared to the price of gas. Greg
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

I said DX, air to air, not geothermal. Greg
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Sorry: When I googled 'DX Heat Pump", the first link I got was to a geothermal install with 14 30-degree diagonal, 50' looks of copper pipe. I'll look again at DX heat pumps, but I must admit it would be easier of folks could cite URLs.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Sorry. First link to a DX heat pump was to a diagonal ground-source using copper tubing at 30 degree off-axis from vertical in 50' excavations. Will look further.
However, our ducting is sized for the higher heat form a gas furnace. The first tech advised a heat pump puts out cooler air and therefore larger ducts are needed, which drives the cost of a heat pump up. Is this not true?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Payback on a 90+ will be much longer in your area. Upgrade your insulation, windows and air seal FIRST. You will then need a much smaller furnace or none at all!
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
I don't know about "none at all" but a Air to Air Heat Pump with a C.O.P. of 3.2 would cost a little less than natural gas to operate, [in most areas except the extreme Norhtern part of the US] but, may not be as 'comfortable' as a "natural gas / propane" fired heater. Are you sure your local utility is not offering any rebates on the +90% furances?
Zyp

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Rebates are as shown elsewher ein this thread, and the $350 extra rebate of a 94% over a 90% sure won't pay the difference in cost.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
I live in a trailer, so it may not convert to your experience. But, I've got three years experience as a HVAC installer, so maybe some of that would be relevant.
How I did it. Well, I was at a seminar on split system AC, and asked if they had any downflow furnaces. The company had a couple left over, a brand they don't sell any more. So they gave me a good price. I took the van and trailer there, we loaded it all up and off I went.
In my case, the furnace was an old Miller downflow. The duct between the furnace and the floor run was nearly useles, and I'm sure I was heating the space under the trailer quite a bit. Of course, I framed that in nicely, and it's very efficient, now.
As for reccomendations, I'd suggest call half a dozen heating companies. See who makes sense, and sounds like he (or she) knows what she's doing. Look for good manners, no swearing, and no pressure on you to make a quick decision.
While installing a furnace, now is the time to consider central AC. Though, it is possible to install the AC coil now, and come back for the outdoor unit later.
The new 90% plus furnaces seem to be the rage. They take a different flue pipe (white PVC) and also require a condensate drain for the water.
As to brands, I don't have a lot of experience. I installed Heil, Rheem, Rudd, and my own unit is a Luxaire. Which I'm told is a York.
Some companies can calculate the heat load of your house, 100K may be too much or too little.
If you have a generator, might be time also to wire in a transfer switch for the furnace, so you can run it off your generator.
I learned that if you want to get flamed, post on alt.hvac.
--

Christopher A. Young
Learn more about Jesus
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Would be pleased if someone can authoritatively answer an unresolved question: Can a heat pump work well in a ca. 1964 house whose ducting is sized for a 100,000 BTU gas furnace?
Thank you kindly.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

How cold does it get outside in winter?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

earlier
Then my best guess would be that a heat pump will work just fine as long as it is sized properly and you have the right ductwork, including adequate returns.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
also, the 100,000 btu heater that you are replacing doesn't tell us anything about your ductwork. To make sure your ductwork is adequate and the heatpump is the correct size, you should really get a pro to do a heatload calculation and another thing they call a manual D(I'm pretty sure that's what it is). This involves measuring your house, including windows, doors and ceiling height and taking note of the N/S/E/W orientation of your house as well as the building materials. Then they enter all that info into some magic software program and that tells them how big of a heater and ductwork you need. Just because your old heater was 100,000 BUT's doesn't mean your new one has to be. New ones are more efficient.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Nobody can answer that without actually being there. If the duct is sized for a 100,000 BTU furnace a similar sized heat pump should work to, but we don't know if the duct work is proper to begin with! Greg
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
obtain manuals D & J from local tech school. Be aware that doing them by hand is a big pain in ass. Properly done each duct should be followed and length and type of fittings, elbows, boots etc noted as air resistance in elbows etc can dramaticly change length rating of duct and thus air flow resistance. stan
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Related Threads

    HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.