7 posts / 0 new
Last post
Choosing a new furnace

Can anyone recommend a gas furnace? I currently have a Mark-Ten which is about 40 years old. (House built in the 70's) It works & has never broken down but I think I should start looking to replace it now. Also, recommendation on contractors for the South Shore.

MLB Construction
Re: Choosing a new furnace

there's many to choose from. obviously i assume you would want a high efficiency furnace. i upgraded ours about 5-6 years ago and it more than cut our gas bill in half. what you need is a good plumber/HVAC guy to come over, see what you have, measure the cubic feet of your home and they can give you several options with different pirces to choose from. my plumber/HVAC guy does work on the south shore. if you want his info, send me your email and i'll send it to you.

Re: Choosing a new furnace

First of all I think that you are lucky to have your 40 year old furnace still working. Who knows how long it can run. But it will be very wise to replace it now, when you're not under pressure to do so.

Like MLB said, a good technician is more than 50% of the battle.

There are many types of furnaces on the market and your tech will determine which one is right for you. Just stay with middle of the road name brand.
Some brands that I installed this year: Rheem, Goodman and Nordyne (maker of Maytag). Lean towards Rheem.

Re: Choosing a new furnace

Get the warranty in writing, and register the unit once you have it in place.

Re: Choosing a new furnace

Not a big fan of FE furnaces at this time. All reports I have seen suggest maintenance costs out strip fuel savings.


Re: Choosing a new furnace

Sealing the ductwork that's in unheated areas would be a good thing to do, too. There can be an incredible amount of energy loss due to air blowing out of the joints. The preferred material is duct mastic. Second option is foil duct-sealing tape.

Do not use duct tape. It may have originally been designed with ducts in mind, but the adhesive dries out and it falls off when used on a duct. Most code inspectors would probably say "harumph" if they saw it on your ducts. Save that stuff for making wallets, shopping bags, holding your car bumper on... anything that's not critical or expected to last a long time.

Re: Choosing a new furnace


When you say "furnace" I assume you are talking about a FORCED HOT AIR heating system, and NOT a forced hot water boiler heating system.

Most of the info at the site listed below suggesting the steps to go thru in selecting a new furnace/hot water/heating system will also apply to the selection of a new force hot water furnace, with or without combining it also with an AC system.

There are also sites below to explain the different types of forced hot air furnace types available, from the standard 80% efficient furnace to the 90+% efficient/ hi-efficiency furnaces---the percentages listed refer to the AFUE efficiency of the furnace---an 80% furnace burns 80% of the fuel to heat the house & sends the other 20% as bad combustion products up the flue to heat the chimney (heat rises) so the dangerous gases will be expelled from the house; 90% to 95% hi-efficiency furnaces burn up to 95% of the fuel & expel the rest in condensate vapor & water that is expelled from the house by plastic drains.

As JLMcDaniel notes, many of these newer hi-efficiency furnaces cost lots more money, are more complicated in design & often require more service calls to iron out the quirks, especially during the first year of ownership; so it often gets to be a pain in the neck to have to constantly call the heating serviceperson while you sit there with no heat; in addition, having a hi-efficiency furnace installed often means that the present chimney can't be used, or requires an aluminum flex metal duct (flue liner--$300-$500) to be run thru it; also, many existing furnace locations (garage, attic, unheated area) are not suitable for condensate drains due to freezing, or drains have to be installed at sometimes considerable expense.

You should therefore discuss these points with the several heating contractors you call to give you estimates---they may suggest that the choice of heating equipment should be based on a less efficient 80% furnace, where you can use existing chimney and existing furnace location, and avoiding other additional expensive equipment like condensate drains & draft-inducer furnace power vents (Tjernlund & others) so you don't incur considerably more expense by installing the higher end furnaces.

Your first step before you install a new furnace should be to evaluate the exterior-walls insulation in your house & have cellulose insulation blown in to all non-insulated exterior walls; this will realize a considerable savings in heating/cooling bills over the year for the cost of a few hundred $$$; also replace any single-pane windows or missing storms with double-pane new windows.

The site below on boilers lists Angie's List ($8 for 1 month's subscription) as well as free sites like the BBB, Yelp, homeadvisor.com, Service Magic & others----I've had good luck with Angie's List, probably because the people who have had a recent furnace installed in the prospective furnace-buyer's geographical area write a "good/bad/fair" review of the job the installer did---this is extremely important because you will be making the very important decision of a contractor selection based on their TRACK RECORD WITH PREVIOUS CUSTOMERS---always get 3 estimates from 3 different contractors in any event, since the choice of equipment, plan of installation & cost of the install will vary widely amongst the contractors.

Well-known, quality furnaces are made by Bryant, American Standard, Heil, Rheem, Thermopride, Trane to name a few; Carrier, Lennox & York are ok, but their furnaces tend to have too many proprietary parts (parts made only by that particular mfgr, unable to be obtained as less costly interchangeable parts elsewhere, thus expensive)---if the local distributor happens to be out of the proprietary part, the customer often waits in the cold till it arrives.

RSTY Thermal (below, Richard Trethewey family heating business/TOH heating expert) is near your area & may be able to refer you to a reliable installer.

You will have to make the decision whether to install at the same time an AC system, that will use the same heating ducts, or make other arrangements for summer cooling.


Sponsored Stories

TV Listings

Find TV listings for This Old House and Ask This Old House in your area.