repalacing a 40 year old standing pilot furnace
I am very soon going to be purchasing a new furnace. I own and live in a 1-bedroom condo in Denver, Colorado. it is about 700-750 square feet, all on one floor.
The condo was built in 1972 as an apartment and was "converted" to condos about 1979. It has the original 40 year old standing pilot furnace that is still in working order (I had it checked in Dec. 2011 by our local utility, Xcel Energy and it passed with no leaks or CO problems. Yes, I have a CO detector installed!)
Since these units were built as apartments there are no separate gas or water lines for individual units. I pay a monthly maintenance fee and the gas/water costs are taken out of that. Therefore whether I have the present furnace or a new 96% efficient energy saver it will make no difference in my utility costs.
I have decided to replace it with an 80% AFUE furnace.
The building I live in has two stories, four 1-bedroom units on the ground level and 4 identical units on the second floor. I am in a ground unit in the middle, so I have other units on either side of me as well as someone above. Below me there is a crawl space. I only have two walls facing the exterior, a north and a south wall.
There are a total of 203 condos in this complex so there are other buildings and 40-year old trees surrounding me.
The furnace is in a closet in the hallway. The closet interior is 22-1/2 inches wide and the doorway is 17 inches wide. I will need to go with a 14 inch wide furnace in a downflow configuration. (the present furnace is 16-1/2 inches wide.)
I have had two installers come to make a bid on a new furnace. They both said I needed a 45K model. The first installer offered either a Trane XL80 or an XV80.
(It turns out that the XV80 doesn't come in 45K, 60K is the smallest. What really puzzles me is that the product data sheet says it is 19-1/2 inches wide! How are they going to get that through a 17-inch door opening? Do they know about some law of physics I don't know?)
A second installer offered initially a basic Payne 80% model. (He also has available Goodman and Bryant models.)
No, nobody did a load calc.
I am inclined to go with the second installer. However, I don't want the basic 80% model from Payne/Bryant/Goodman, I'd like to upgrade to the best 80% model I can get that will still be 45K.
So to that end, I have been poring over furnace reviews, forum posts and product data sheets. I have learned a few things and it has been challenging and interesting, almost fun!
I realize with the furnace in the hallway right next to the living/dining area it would be a good idea to go with a furnace with a variable speed blower and a 2-stage burner.
The top of the line 80% models from Bryant (Evolution 80v-315AAV) and Payne (PG8MVA) offer these features and they would be perfect except for one fatal flaw: the smallest they come in is a 65/70K model. I know this is WAY too big for my unit and have read of the horrors that furnace oversizing brings. I know then that I cannot choose these.
The mid-line models from Payne (PG8MEA) and Bryant (Preferred 80x-313AAV) have more features than the basic models but still only 1 stage burners and multi-speed (not variable speed) motors.
Goodman only seems to offer only one 80% downflow model, the bottom of the line GDS8. I have found distributors on the Internet offering a Goodman GDH8 which is a downflow 80% model with a 2 stage burner (but still a conventional motor.) It is not listed on Goodman's site so I'm guessing it is discontinued.
When I asked the installer about the mid-line Bryant 313AAV, he said it was not stocked by his distributor and it would have to be ordered direct from the factory, there would be shipping and handling charges. The Bryant 315AAV was stocked and so he could offer it at the same price as the 313, but as I said before the 315 is not available in a 45K so it's really not an option.
I see Bryant also sells another mid-line 80%, the 312AAV (Preferred 80t). This does have 2-stage heating, but from what I read on this forum, only a PSC motor. Not good.
In short, there seems to be no model anywhere, from anybody that is an 80% AFUE, 45K, 2 stage burner with variable speed motor. I will have to compromise somewhere. And I am very inclined to go with the Bryant 313AAV.
By the way, I do have air conditioning and the evap coil needs to be replaced. (I had a repairman come in about 3 years ago to do a heating/cooling seasonal startup. He said the evap coil was totally clogged with dust and dirt. He could attempt to clean it but the metal looked so old and brittle that he could not guarantee that it would not start to break apart during the cleaning. I am sure it has probably never been cleaned in the 40 years it has been here). The A/C does work but it doesn't get quite as cool as it did when I first moved in.
As for the AC compressor, it is still the original unit. I don't have to worry about any costs replacing this, as the condo management will repair or replace the compressor at no cost to me. (in basic terms I pay for everything "inside" i.e Furnace, evap coil, etc and the management pays for the "outside" equipment-the compressor.)
The install prices will include replacing the old evap, coil with a new r22/R410 compatible unit, put a filter on the refrigerant lines and deep clean the lines down to 500 microns.
The first installer asked $3589 for the XL80 install with a new coil and $3889 for the XV80 upgrade. The second installer wanted $2200 for the Basic 80% Payne or Goodman, $2350 for the basic 80% Bryant) and $2750 for either Bryant 313AAV or 315AAV, all with a new evap coil that is R22/R410 compatible.