Sounds like propaganda to sell new furnaces. I hate that crap. Especially with gas furnaces, they can be neglected for a year or two with nothing really bad happening to them aside from a dirty filter.

I would find out the true overall efficiency on my own by keeping an annual record of oil consumption vs annual degree days. You call up your friendly oil company ( the one pushing a new furnace) and find out the degree days in a particular year. If you divide the annual oil consumption by degree days for that year, you get a meaure of the effiency which includer the filter and cleanliness of the heat exchanger. It is that number that should be scutinized, not the oil company's efficiency, which is only an estimate of the fuel burning efficiency, not the bottom line number I am proposing.

Joeplumb, 80% efficient furnace. I think he's talking gas fired here not oil. If it was oil though you'd loose that 1% every week practically.

Give me a break. I go away on vacation and this slips in. :) Oil furnaces of that era probably were 80% efficient. Keep the heat exchanger clean and the oil gun tuned up and it should stay as efficient.

"If it was oil though you'd loose that 1% every week practically"

what the heck r u talking about???, i hope that was some kind of wierd joke that went over my head, because taken at face value it's total bs.

Ok thats somewhat an exagerated number but go ahead and pull an efficiency test after the system has been cleaned and serviced and then try pulling another one at the end of the season. You don't think there's a serious drop in the number? Then why do oil systems have to be thoroughly cleaned every year? And that ain't no BS!

With the clean burning oil burners of today, with zero smoke, oil valves, pre and post purge, you can probably get away with cleaning every other year.

Add an airboot kit to draw in outside air and it's even better.

True, but your efficiency still drops. I don't care how well it's set up and what bells and whistles you have on it its going to soot up and even a very light coating of soot reduces efficiency.

That's true, but the sooting is very minimal compared to just a few years ago on a properly burning unit. Settings don't change, but the air inlets to the burner get clogged with lint and animal hair and that throws it way off.

A better idea is to make sure the chimney base is open and leave the tune ups to alternate years.

Have they developed oil burners that can sidewall vent? I know a standard oil burner is supposed to have -.05" W.C. draft in the stack, but with a forced-draft oil burner it can't be that hard to design a unit for sidewall venting and eliminate the need for a chimney altogether.

yes, they are called direct vent and they use a power venter and vent kit. They don't need a chimney. As long as the proving switch works, you're in business.

There are restrictions about where they must exit the house.

I know sidewall venting with oil (and gas in some cases) can still be pretty hot gases, probably need to kep them away from painted surfaces and vinyl siding.

It takes special brushes & vac hoses to clean the soot from an Thermo Pride Oil furnace heat exchanger.
Get them & do it right! udarrell _ 2007

Here is a link that might be useful: udarrell.com

From our experience with thousands of our fuel oil and LP customers, we've heard every story imaginable. The market is flooded with used car salesmen types looking to replace parts, replace systems and/or perform unnecessary service. Any stories the salesmen can fabricate, or any myths they repeat potentially puts money in their pockets. The inefficiency of all furnaces & boilers over time myth is funny. My favorite oil burner myth is that oil companies with service departments install larger nozzles to sell more fuel. LOL. Gas service people often tell oil customers that their systems drop dramatically in efficiency in a short period of time in order to make a sale. Most inefficiency we see is due to a combination of improper sizing, burner setup, zoning and system design including, boilers, furnaces, water heaters, indirects, ductwork, boilers, piping/pumping/controls and building envelope issues such as old windows, doors lack of insulation etc.

Annual oil service consists of a cleaning, combustion test, filter change, nozzle change, strainer change, pump pressure test & testing safeties and general safety inspection, so It's not just about cleaning the unit. Besides servicing the heating equipment annually, you also make other safety checks plus other visual preventative maintenance observations as well. You check for or observe potential problems with combustion chambers, heat exchangers, boiler blocks, ducting, piping, wiring, leaks, air intakes, exhaust venting, roof jacks, powerventers, chimneys, aquastats, low water cutoffs, pressuretrols, circulators, valves, zone valves, indirects, control strategies, water feeders, expansion tanks, backflow preventers etc.

Oil service techs are generally in customers homes on an annual or semi-annual basis, so while they're performing annual service they see more potential problems with other system components, (including gas fired equipment) as well as other structural and mechanical problems in homes. Because oil service techs are in customers homes so often, the preventive maintenance observations and human networking factor lead to a lot of other work, and referrals.

Modern oil fired units are very clean, but they still need to be setup by a professional that performs a combustion test. I perform safety inspections and combustion tests on my own systems annually, but don't always clean them, or replace nozzles filters and strainers every year.

One reason we see so many dangerous situations with our gas customers is that they never have their units inspected, serviced or replaced until the unit fails. We often get a call when the CO detectors have gone off, or when someone is feeling sick due to an exhaust leakage, blockage or cracked heat exchanger etc. Many people are unfamiliar with oil burning equipment, and don't have the knowledge, tools and parts to perform service and installations, so the market tends to be over-saturated with gas installers willing to work for very little money. This creates some dangerous situations combined with lack of combustion testing and customer neglect.

Besides powerventers, there are direct vent boilers and now condensing oil fired boilers as well, although the majority of our customers use traditional chimney vented oil fired equipment. I think Olsen makes a direct vent forced air furnace as well.

You said: I perform safety inspections and combustion tests on my own systems annually, but don't always clean them, or replace nozzles filters and strainers every year.

No problem with the post, but I would definitely change the nozzle each year.

baymee- I agree in the majority of situations. We always replace nozzles/filters/strainers on all customers systems unless they don't want us to.

Nozzles can run for years as long as your tank, oil, line(s), fittings, filter(s), strainer are fairly clean, you're running a single line system and your burner is set up properly. When I pull my strainers, they're always clean as a whistle since nothing gets by my spin-on filters, and oil treatment keeps things clean as well

I run dual filters (Primary 50 Micron, Secondary 10 Micron). I also have Oventrop floating suction withdrawls on some systems, single line oil supplies on all systems and we treat our oil. I replace the primary filter elements twice a year, but only replace the secondary 10 micron spin on filters when the included vacuum gauges read high. I always check the strainer, and always perform a combustion test.

As far as cleaning is concerned, I always open the door on my horizontal three pass boilers to check the condition, and open the combustion door on my Hallmark scorched air units to check the condition. When the burners are set up properly, and when boilers are piped properly, you shouldn't have much to clean. I used to experiment by setting up different burners and piping on boilers notorious for plugging since I love a challenge. Although some boiler manufacturers require bypass piping, rarely do you see bypass piping in the field.

Bypass piping has the advantage of tempering the boiler to a uniform temp. It makes for more even heating and on the larger boilers, it's required. It also prevents the cold return water from making the boiler sweat, thus prolonging its life.

You must live near PA if you use Hallmark furnaces.

Some people install modern boilers on large single zone systems, and older large water content systems and shock the boiler with cool return water. This also creates soot in some tight pin style boilers, and boilers with unlined combustion chambers.

All of my boilers are well balanced, and connected to indirects running year round as warm start boilers. I also run stainless chimney liners, so I don't have condensation issues on the other end.

"You must live near PA if you use Hallmark furnaces".

I'm in Upstate New York. We have more boilers than forced air systems, but we've used mainly Thermopride & Hallmark furnaces. Before we sold off some the business & territory, we used to stock quite few Hallmark furnaces. I like the open access to the heat exchanger/combustion chamber and the front or rear flue connections are nice since they eliminate stock.