Central heating systems

[Cybrvanr]

There's a neat show on the history channel tonite about the history of heating and cooling systems. Heating and cooling systems are perhaps one of the the most significant inventions that have changed our modern lives. Only recently have we been able to change the climate in the environment we live in.

I've always wondered about the nomenclature of the term "central heating (or cooling)" The term "central" is used to describe heating and cooling systems that evenly distribute the warmth throughout the structure through pipes and ducts.

This is in contrast to previous versions of heating systems, like wood stoves, that only heat a single room. I would think that the term "central" heating system would describe a heating source like a wood stove or a floor furnace much better. The term "distributed heating" more approperiatley describes modern systems with pipes & ductwork that heat and cool all the rooms of a building.

Although not as glamourous as stoves, washers, fridges, etc, HVAC systems are one of the most significant appliances in our homes. Interestingly enough, there is very little in our history books about heating and cooling systems, and people are hardly passionate about them either. Still, I find the boiler rooms of old buildings absloutely fascinating! Especially the ones heated by steam, with their big fire boxes, pipes, and other machinery. On a smaller note, I have fond memories of air conditioners in my past, like the GE zone-lines in my grandmother's home, and the old Sears Coldspot unit (RCA Whirlpool) that my parents were given in the eighties...previously we had no AC in the home until that unit came, and just the sound it made was comforting on a summer's day!

 

[petek]

An oddity I'd never heard of before until I moved to Vancouver years ago was steam heat being piped into office buildings and business' in a downtown area from a privately run steam generating company. As far as I know it's still there running and heating many buildings in a 4 or 5 block area. On cold days you see steam billowing out of some of the manhole covers along the streets.

 

[jetcone]

Yes Petek

that is called District Heating and that actually was the first kind of central heating.I think it was first put into use (non commercially)around 1830 for the US Navy at Norfolk VA.

But there is a fascinating tale of the Boston Heating Company here:

http://www.energy.rochester.edu/us/ma/boston/bhc/

 

[DADoES]

<blockquote>Interestingly enough, there is very little in our history books about heating and cooling systems, and people are hardly passionate about them either.</blockquote>Ohh, nooo, I'm quite passionate about air conditioning and heating ... in my house, my grandmother's house, businesses where I work, etc.

 

[kenmore1978]

Central steam heat

Con Edison still runs a steam heat business in New York City

http://www.coned.com/newsroom/energysystems_steam.asp

 

[toggleswitch]

The perfect climate

Glenn and all:

Interesting that heating and cooling is fascinating to me too.
Perhaps we are all frustrated potential mechanical engineers and climate-control engineers!

Deisgning major/large heating and cooling systems would be my ideal career.

IIRC Consoldated Edsion (the NYC metro area utilty) provides steam heat using the waste heat from electrical generation plants (one is affectionately known as "Big Alice").

IMHO district heating is a great way to recover the 2/3 of the energy wasted as heat when producing electricity.

If I had my way we'd be burning garbage also to make electricity, rather than bury the garbage or "bury" at sea. At least if burned, the smoke stacks could be "scrubbed" minimizing pollution. When buried, the toxins get into everything, unmitigated.

 

[toggleswitch]

Central heating

I believe the name central heating comes from the point of view that the combustion is in one place-centalized. this is important in place like NYC in that even small brown-stones (attached townhouses) could have 8 apartmetns with three chimnies each.

It was much safer to have one main boiler in the basement (on a concrete floor) raher then many many many parlor stoves or gas unit heaers.

At least if you drape clothing over a radiator to dry, it can't ignite. Do the same thing or even get too close with a unit heater and there is a potential fire hazard.

Also unit heaters need oxygen, so it was impossible to double-glaze windows or overly seal the living space from the outdirs. Drafts were created when the by-products of combutsion were sucked up the chimney and make-up air seeped in from every crack and orifice.

I beleive the law in NYC requires heat during the day (6am to 10pm) and not at night:

1- To mimic the natural patern of warmer days and cooler nights.
2- The coal-man who had to shovel coal in had to sleep too!

When gas lighting got phased out and unit heaters did as well, aparments got much cleaner and air quality increased tremendously, IMHO.

 

[jamiel]

Lots of electric utilities have steam subsidiaries...I believe Union Electric (St. Louis) and Missouri Public Service (suburban Kansas City/St. Joseph) both do. It's regulated, as well (just like electricity.

 

[toggleswitch]

How do you heat a skyscraper?

NYC sky scrapers need an outside source of heat.

Can't put the boiler in the basement, because getting the flue gasses to the top is a problem. Too cool and the caustic acids condense and eat the chimney/fluepipe.

Can't put the boiler on top because getting the fuel oil to the top is a pain, and not good to store so high in case of leaks. Natural gas is too expensive to use for such large loads, and you'd have to agree to interruptible supply to even get permission to use it for such a large load. (this is to ensure there is plenty avaialable during peak demand for small residential users).

Also, early skyscrapers had steam heat which needs to be fed from the bottom. In larger/taller buildngs a two-pipe system is used with a vacuum sucking the condensate return back. It Forces steam up higher and faster. Thermostatic automatic mechanical steam traps are used to ensure live steam is not sucked back into the condensate return side.

http://www.bellgossett.com/WhatsNew/prd-17Feb05.htm

 

[launderess]

NYC mandates indoor temps reach a certian level both day and night based upon outdoor temps. Not sure of the exact date of the NYC "heating season", but during that period landlords are required by law to provide heat based upon the above. Failure to do so results in violations and in worse case the city will make repairs to the boiler/provide fuel/etc and bill the landlord and or put a lien on the building.

Con Edison's large steam plant near the UN was sold off, it will be torn down and luxury condo's built in it's place.

Launderess

 

[launderess]

District Heating

Is quite popular in certian European countries and much of Russia. Also there are plans to get many rural Chinese areas on board also to cut down on all those individual coal heating sources.

Launderess

 

[dalangdon]

The Omaha Steam Plant

When I was a little kid, it was a special treat to go by the steam plant in downtown omaha. It was built in the 50's or 60's, and had big glass windows on the ground level so that you could see the machinery, which had been painted bright colors. It was quite a sight at night.

 

[toggleswitch]

Laundress:

Yes, regarding NYC required minimum indoor temps:

HeatTimer brand controls asppear to be the local industry-standard when it come to temperature regulation and fuel economy. In this device, there are outdoor temperature sensors and indoor ones as well. The oudoor ones ensure there is heat when at or below 55*F outside.

The heat timer allows adjustment of the burner cycles via a dial with letter "A" through whatever, to ensure that the burner runs long enough to build up a head of steam and ensure it travels to the furthest reaches (radiators) of the buildng.

Funny how lanlords seem to have to buy the computerized verison that records the temp in the building and the burner cycles. This is counter nuisance tenant clams that "there is no heat". Most often landlords tell me these tenants who complain about everything are the ones who say to the judge in housing court, "The landlord don't like me because I'm ___________ "(insert adjective). After a certain number of nuisance clams the tenant gets legally booted if the LL wants to spend the $ to do it.

anyway here is a link to HeaTimer controls

http://www.heat-timer.com/?page=appover

 

[toggleswitch]

NYC regualations, heating

Here it is in officially in writing..
minimum temperatires required.

see section 27-2029

http://housingnyc.com/html/resources/hmc/sub2/art8.html#27-2029

 

[DADoES]

Wow. Not ever having lived anywhere but here, where heating season is no big deal, it would have never occurred to me that a city could/would have *laws* regarding indoor temperatures! Details on the system infrastructures of large commercial buildings is fascinating.

 

[toggleswitch]

Glenn is that an invitation to keep you and others posted ? LOL

I really LOVE looking at boiler rooms as part of my job.

BTW my brother-in-law is an electrician by trade and asked ME to tell him how to wire his new heating systen. I was honored.

That is an accomplisment for an accountant / real-estate appraiser, eh? LOL

As I always say, if you have to learn it from a book, you are not passionate enough about the subject.

 

[Cybrvanr]

That's very interesting. I noticed though that I would be in violation of that law the way I keep the heat in my home during the coldest part of the winter. My electronic setback thermostat keeps the temp at 60 degrees between 10PM, and 5PM the next day. Between 5PM, and 10 PM, it brings the house up to 68 degrees when I'm home, and on the weekend, it stays at 68 degrees all weekend long.

This law does not appear to be for landlords only, so I imagine it applies to single-family homes too! Well, I don't live in New York, but I wonder what my own zoning laws look like

 

[Kevinpreston3]

Misc thoughts.....

So, that is what is behind the NYC shots in movies where there is steam coming up from manholes!!!!! Always wondered what that was, and this is all news to me.

Here is an odd cooling story.

About 20 years ago, my sister moved into an apartment that was a very old, although renovated, building.

When she was moving into the kitchen, one of her kitchen cabinets was very odd. It was long like a broom closet or pantry, but it was not very roomy inside. There was something inside at the back that was unidentifiable. She was always curious what the deal was.

In casual conversation, she mentioned it to her landlord. He told her that a long, long time ago, there was some sort of system in the basement that was an ancient refrigeration unit. Each apartment had one of these cabinets, and there were tubes from the main unit that ran up to each cabinet.. They called them a refrigerated cabinet. They were not supposed to be a fridge or a replacement for the icebox. They were a cold cabinet I guess to store certain things to make them last a little longer...I would imagine fruits or maybe some types of leftovers, I am not sure.

Is that wierd, creepy, bizarre, or all three?

 

[launderess]

Heating Laws In NYC

Like much else in NYC the laws grew out of reaction to complaints to local government about some landlords being stingy with heat. Back in the bad old tenement days and probably still, some landlords were famous for taking rent and providing little if any basic services. One could be living in a rat infesting cold water flat, and complain until blue in the face, and get no results, but be late with that rent check and see what happens.

Even today when NYC goes into a "deep freeze" there are landlords who will not provide heating levels provided by law. This is not only shocking but a serious health hazard especially to the very young and old.

Also without heat from the boiler, tenants start using their ovens or space heaters for warmth. These can cause fires or death,which am sure was one of the reasons behind the law forcing landlords to provide heat. Modern gas ovens reliable, but can imagine many people turned their ovens on for warmth and went to bed never to rise again. Then there is the risk of buring down an entire building from a gas explosion or heater fire.

Many people think owning a rental property in NYC is a ticket to easy street, and have no idea regarding costs. When those heating oil bills come in, not to mention the cost of running and maintaining a boiler (NYC has some of the oldest housing stock in the country, and boilers are frequently kept running long past their sell by date. Mainly held on with every trick in the book to avoid the expense of a new boiler), some landlords simply just cannot afford to fill the tank/pay the gas bill.

Launderess

 

[toggleswitch]

BTW=> the cost of running a muti-family apartment building in NYC is 40-60% of its income. BEFORE THE MORTGAGE PAYMENTS.

Real estate taxes are typically 10 to 20% of income.

Heating costs are typicaly not less than $200 per room per year with a range of $700 to $1,000 per residential apartment per year.

Management expense is typically 3 to 5% of income.

Reserves for replacements are typically $125 for a walk up and $150 for an elevatored buidlng per unit per year. This is to have funds aside for replacement of roofs, boilers, sidewalks and other major capital improvements.

Utility expense to provide common hallway lighting is approximately $90 to $200 per unit per year.

Water and sewer charges are typically $350 to $475 per unit per year.

Rents here are high because expenses here are high.

Newer concrete fireproof buildngs frequently still provide central hot water and gas (unmetered) with which to cook. Oddly they include PTAC units to heat and cool. these ARE metered to the tenants. Think 42 inch wide (1 meter +) hotel/motel heat pumps.

http://www.friedrich.com/ptac/index.asp?divname=resd&resetdiv=1

 

[toggleswitch]

Cybrvanr-

Yes technically it applies to landlords in muti-family buildngs, where the heat is not indiviadually controlled and metered.(i.e. Landlord pays). However it is the de-facto expectation of all tenants even those renting space in a private (read: laws not applicable) two-family home where the owner pays for heat.

Normally lasnlords provide more than the minimum temps (during the times they are obligated to do so to avoid legal entanglements) however the theimes the heat comes up and gets turned off is pretty much to the minute as pescribed by law.

Sometimes a nice landlord will let it run later on Thanskgiving, Christmas, New Year's Eve or other holidays celebrated by the majority of the tenants. No extra heat provided /required on Valentine's day. HA HA HA LOL.

 

[toggleswitch]

Let me explain how my old landlord got around the heating requirments-

It the building is owner occupied or has the owner living within XXX feet of the property, a superintendent is not required. (He himself is acting as the superintendent).

He would sit in his (heated) retail store adjacent to the (cold, unheated) apartment building. If the inspector came during the day, his wife would go out the back way and into the buiding the back way, and she'd turn on the boiler. then he would call her and say, "Honey would you kindly bring us the keys to the boiler room?" In the ten minutes it took to play this charade, the boiler was ignited, hot and pushing steam into the radiators in the residences.

Of course now he could call into a modem and turn it on by phone right in front of the inspector and get sway with it.

so by providing heat from 5 to 10, twice a day, he got away with murder and managed to get the old people (who were home all day) to move out. This worked equally as well for pepole with young kids, and those who chose not to work (read: secion 8 et al). The tenants were basicaly all working couples. Hugely ideal, hugely illegal.

 

[bostonwash]

So much knowledge here.

I read that in NY , at one point, they also had interconnected pipes from a circuit of buildings for freon gas for air conditioning in the summer.
I'm thinking that didn't work too well. It seems like most of these skyscrapers have massive air handlers on the roof for AC.

What an interesting history there must be under the streets of old cities.

 

[launderess]

Nice story but, in NYC it is not the just the boiler operating,but the temp in the apartments which matters.

If a tenant files a complaint regarding lack of heat/hot water an inspector will show up with a meter in hand to check the indoor temp of that and perhaps other particular apartments. They will also turn on and stick a thermometer under the hot water tap to see what temp is coming out.

Even if say the boiler room was a sauna and one could "hear" steam in the pipes, the landlord could be sited for lack of heat until he "repairs" the boiler.

Tenants whom have contacted NYC to complain about lack of heat are always advised NOT to turn the oven or any other heat source on before the inspector arrives. This is because if the indoor temp of the apartment is over a certian temp, regardless of how it got there, a violation cannot be written. The code only specifies what the indoor temp must be, not how it is arrived at, so off the oven goes.

It is going to be interesting if this winter is very cold with heating oil/gas prices what they are. Large landlords with many properties to heat probably have locked in oil prices already. However the small landlord is going to be in for a rude awakening. Also many large apartment buildings have dual fuel boilers, which are set to use the cheaper fuel when temps drop below a certian point.

Launderess

 

[toggleswitch]

Many tenants IMHO are used to 72*F to 76*F and anything below seems cold to them. Reaching the required 68*F minimum room temperature from say 66*F would take only a few minutes with a steam system. These older systems typicaly had "overkill" sized radiators, perhaps to facilitate a quick temperature recovery from the nightly set-back temp, and to be able to maintain the legal minimum when outdoor temperatures are in the teens.

 

[toggleswitch]

If rising interest rates don't kill the price of real estate, heating costs just may!

 

[kenmore1978]

temps

In my house 68 degrees is whenit starts to feel "chilly' and I turn on the forced air gas furnace. I then set it to 72 degrees with the fan constanly running to even the temps throughout the house and keep air flowing past the thermostat for more accurate cycling.

 

[Brent-Aucoin]

Interersting topics!

This is all so interesting. I have always loved heating and cooling for houses and buildings also.
Does anyone know when this program will run again on the History channel? I would love to see it, and hate that I missed it.
Steve, do you have any pictures of dangerous boiler rooms, and furnaces? There was a website a few years ago that posted pictures like this, but I can't find it anywhere.
Thanks for all the interesting chat!
Brent

 

[Cybrvanr]

I don't have anything like that, as I don't get into the basements of older homes and building too often anymore. I do remember that someone here did post something like that. The curious thing was that while other kids were afraid of going down into the basement of an old house...that's where my parents could find me when I wandered off at a visitor's house. I found the huge, fire-breathing beasts in some of the old city homes absloutely fascinating with all the pipes, gauges, valves and stuff. When they lit up...awesome!

Today's HVAC plants, although quite amazing in their capabilities...like being able to monitor and control each room's humidity and temperature though a web browser, they are actually quite boring from a visual perspective. Most mechanical components are covered up and are internal. They make less noise, and overall are simpiler in their assembly.

 

[foraloysius]

Steam pipes

I had no clue either what these steam pipes were for, but Steve explained that to me when he showed me around in NYC. Here's a picture I took this summer.