Some things I need to know:
Do you have zoned system? A zone will have two distinguishing factors ( 1) it'll have it's own thermostat on the wall and (2) there will be a "zone valve" (usually Taco or Honeywell) in the celler near the furnace.

Are the heat exchangers Iron? Or are they copper pipe with radiant fin aluminum crap? (the heat exchangers in question are the radiator in the rooms)

Is the system forced how water or steam?



:::::::::If it's a forced how water system:::::::::::

Think about replacing every single valve you can with a nice new modern Ball Valve.

Replace the inlet and outlet valve to the furnace with nice huge ball valves.b Chances the old valves are shot anyway.

Place the recirculator motor ON the TOP of the new furnace not down on the side at the floor. Some plumbers like to put it at the lower end. This is fine except a lot of such placements cause an air bubble to form in the recirculator and that causes burn out of the newer recirculator pumps.


Add two Ball valves to the upper and lower side of each zone valve. This helps to isolate the whole system during shut down and maintainance. More is always better when it comes to valves. And ball valves don't hinder flow.
Never install any other type of valve. Those old school rising stem valves are all dinosaurs that should be thrown away

The modern furnaces are pretty damn good. I'd look at a Weil McClain. If you go with a new high efficiency furnace and you don't have cast Iron heat exchangers you might want to think about adding a water ballast tank.

A ballast tank will help prevent the furnace from cycling on and off all the time. It'll be a stainless steel or copper tank of a few hundred gallons that you will insulate very well.

The good news is that the new furnace is lighter than the old one. You will still need a couple of beefy guys to muscle and rig the thing in position. I did mine alone using a dolly and some ramps and some ropes and block and tackle I got the thing from my pickup in the the driveway into the garage into the cellar up a couple of stair steps and into the place where it had to go. My cellar is 250 years old and the beams are 8 and 10 inches of solid oak. The oak beams above the furnace's final position I drilled the holes for the ropes which I used to lift the furnace up and settle it on the concrete blocks which I used to keep it above the floor.
Never set a furnace right on the floor. A tiny little bit of water in your cellar will ruin your furnace.

This will be a good time to take a long hard look at other elements of the system and determine whether they need replacement.

Do not add anything to the heating water such as an anti rust treatment UNLESS the boiler manufacturer has approved it. Otherwise you might as well throw your warrantee away.

Crown is an older company. I don't know anything about them.

It's not that hard to do. My last replacement job was in my first year of law school. It was late october damn cold and the old one burst.

The first year of law school is that year when they make half the class quit from overwork. Between the freezing nights and the demands of school I had little time to spare. Took about 3 days all told.

1. Is this installation to take place within the City of New York?

2. Which utility provides you with gas?

Grouch,
Your comments are way off base. She did say "her husband" wanted to do it.
Your 2ed line makes no sence at all.
Rember kids, don't drink and type.