Oil to Gas Conversion: Questions

I hope answers to these questions, from Master Plumber and others on this forum, could guide us and anyone else considering an oil to gas conversion.
We’re looking at such a conversion this spring for the steam-heat system in our 1914 attached, single-family brick house .
1) How does a plumber determine the size of the gas furnace needed? What should I expect them to check during a visit to provide an estimate?

MP:
In a steam-heating system, a plumber measures the surface area of all the radiators in the home and comes up with something called a number of Equivalent Direct Radiation (EDR). With boilers, the rate of production of steam is rated in terms of square feet. The EDR number must closely match the replacement boiler’s square feet of steam output.
The way NOT to do it? Put back the same size boiler that’s there now without doing an EDR calculation. Nine times out of ten that leads to the purchase and installation of an oversized boiler, and a 20-year commitment to inefficiency and breakdowns.

2) How does a plumber determine if a chimney liner is needed with a new furnace? If a new liner is needed, should the property owner first contract with a chimney specialist to have this work done?

MP:
In the case of replacing a new old-style cast iron boiler, such as any steam boiler, a “plumber” shouldn’t be determining this. I always advise my clients to seek the advice of a qualified chimney and flue specialist. A trained eye will recognize a breach in the old masonry or a compromise in structural integrity. It is a completely different skill set from the plumber’s and not something to guess at or experiment with.
In the case of a newer, high-efficiency boiler, you need a chimney liner or a dedicated PVC or aluminum flue. Masonry chimneys can not safely handle the corrosive vapors emitted by high-efficiency boilers. Your installer should coordinate with the chimney contractor to determine whose work gets done first.

3) Since the conversion will likely requirement some movement of asbestos covered pipes connected to the existing boiler, should a property owner first contract with an asbestos-abatement specialist to remove the pipe wrapping, before working with a heating contractor?

MP:
Yes. You’ll need to file an ACP-5 form certifying there is no asbestos in the work area anyway.

4) Can the plumbing contractor also remove the un-needed oil tank? Or, again, should an owner contact a separate company for this work after the oil line is disconnected.

MP:
Only companies certified, I believe by the DEP, to handle and transport fuel oil can legally drain and remove your tank. This company will also have the authority recognized by the FDNY to certify the tanks and their contents were removed safely in the event of a fire inspection. I don’t know any plumbers that carry this certification. Again, this is best handled by a qualified company that has trucks, cutting torches and pumps set up specifically for this purpose.

5) Should a plumbing contractor be responsible for any necessary permits and/or contact with Keyspan aka National Grid?

MP:
Yes.

6) In this house, the existing oil burner is partially enclosed in a closet constructed of wood-frame and gypsum board. The front of this closet is fully opened, allowing the face plate of the oil burner to be removed for cleaning and maintenance. Am I correct that such an enclosure now violates the NYC building code? Does the owner need to remove this enclosure before contracting with a plumber?

MP:
It depends entirely on the tolerances, clearances and venting requirements listed in the manufacturer’s specifications of each individual boiler. Some units are suitable for closet installations.
That said, an architect can tell you that multi-family buildings may require the boiler be set in a two-hour fire-rated mechanical room.

7) How can an oil furnace be enclosed in a basement that may be used in the future as a living area? Does the furnace require specific clearances on ALL sides either for maintenance access and/or building code requirements? Are removable metal screens (such as larger version of radiator covers) an option to enclose the furnace?

MP:
See 6.

Good luck with your conversion.
http://www.GatewayPlumbing.com

Posted by: Master Plvmber at February 3, 2009 4:39 PM

You're welcome.

"High efficiency" at this point means 90%-96%, where it used to mean any boiler in the 84%-88% range, which we now call mid-efficiency.
To get the higher ratings, boiler venting has had to be redesigned entirely.
As a result, HE boilers tend to require vent and intake ducts direct to the outside. That makes nearly all of them suitable for closet installations.
Originally, their intended venting design was to pipe them right out a building's side (or rear or front) wall maintaining up to 5 feet of distance from doors and windows. As popularity increased, the HE boiler market expanded to include installations in the replacement market in major cities and so increased the need for boilers that could tolerate more venting designs.
Now we've got options to vent boilers to within one foot of a door or window, so you might not need to line your chimney at all if you can figure out a way to use a cellar or basement wall as a termination point for an HE boiler's exhaust.
If not, you'll have to use the chimney as a chase and drop a couple of pipes down it and connect them to your boiler.
And you're right, expect to pay several thousand dollars for the task.
Fortunately, doing that now sets you up for any future high efficiency equipment.

If you want to use your existing, unaltered chimney, you'll have to stick with standard efficiency.
The reason is that boiler and water heater exhaust gases that are under 350 degrees contain a corrosive dose of vaporized carbonic acid. Brick and terra cotta chimneys disintegrate when they come in contact with that stuff. The very idea of mid and high efficiency boilers is that they extract heat from the flue gases thereby decreasing the exhaust temperature to that critical point where they need something corrosion resistant to work safely as a flue conduit.

I hope that is all follow-able. (if that's a word)

http://www.GatewayPlumbing.com

Posted by: Master Plvmber at February 3, 2009 8:36 PM

I use this company:
Evertight Tank Corp.
718-981-1818
They pump out the oil, cut out the fill pipe and cement over it as required by code, and cut out the tank without destroying your house.

Tell them Gateway Plumbing referred you. They don't advertise and respond well to word-of-mouth work.

What they'll also do is sell you small amounts of oil if you need it to get through a week or so while your conversion is in progress.

Nobody I know buys your old oil, though. Once it's in your tank, it's considered contaminated.

Posted by: Master Plvmber at February 4, 2009 7:39 AM

Correct.

Posted by: Master Plvmber at February 4, 2009 4:07 PM

No. What cmu is correctly saying is that there are no high or even mid-efficiency steam boilers on the market.

If your brick chimney is in good shape and can handle the boiler you install, then you're done.

If not, you'll have to reline it.

Your only other option with steam is a power vented boiler that also vents out a side wall but burns at the same efficiency.

Posted by: Master Plvmber at February 4, 2009 10:22 PM

No problem.

You've got it.

When you convert from oil to natural gas, as part of the DOB filing, you'll need to certify the chimney's fitness for use in the application.

The exhaust of an oil boiler is very different from that of a gas boiler (different moisture content, soot sticks to the walls with oil, gas dries it out and the stuff can fall in and block the flue) and so a smart thing to do is have your old chimney thoroughly cleaned and inspected near the time of the conversion.

A smart plvmber will let a good chimney contractor take care of all that and hold him to his evaluation.

Again, it's just the smart way to do it.

Posted by: Master Plvmber at February 5, 2009 7:58 AM

No problem.

You've got it.

When you convert from oil to natural gas, as part of the DOB filing, you'll need to certify the chimney's fitness for use in the application.

The exhaust of an oil boiler is very different from that of a gas boiler (different moisture content, soot sticks to the walls with oil, gas dries it out and the stuff can fall in and block the flue) and so a smart thing to do is have your old chimney thoroughly cleaned and inspected near the time of the conversion.

A smart plvmber will let a good chimney contractor take care of all that and hold him to his evaluation.

Again, it's just the smart way to do it.

Posted by: Master Plvmber at February 5, 2009 8:07 AM

The plumber certifies the chimney. It's a section on the plumber's permit application, but as a plumber who is well-trained and certified in the area of combustion analysis and carbon monoxide detection, I can tell you that inspecting chimneys and identifying/repairing problems is not what plumbers are good at even though they think they are.
It's a skill set best left to those who do it every day.

For that reason, I always follow the recommendations of trusted chimney contractors I work with and I'll certify a chimney unless they tell me it's in my interest not to.

Posted by: Master Plvmber at February 5, 2009 12:15 PM

Christophe, you claimed in another post to have "10 plumbers" quote you on your boiler replacement job.
I suspect you haven't had it done yet because I see no permit in the system for your address. Either that or your plumber just didn't follow through with his responsibility to file.
Your building required a 12-section boiler. That's much bigger than most boilers we see in a residential building. The price I quoted you was more like $11,000, which is what the job was worth if you wanted it done well, with options for commercial and high-efficiency water heaters that certainly do cost more than standard equipment.
If I remember correctly, you were looking to gain efficiency with your new equipment. These were simply options. You were in no way obligated.
Now that you've posted this misleading claim three times, in two different threads, can we leave it that you got other prices more in line with your budget and stop what looks like a personal vendetta against my company?

I don't have a dime of your money and never will.

Move on.

Posted by: Master Plvmber at February 5, 2009 7:54 PM

Outstanding post, Smokychimp.
I've never had a clearer explanation of these points.

Posted by: Master Plvmber at February 6, 2009 5:17 PM