If you have been reading my last few posts about HEATING SEASON, you probably noticed that the posts were about some pretty basic procedures. There were posts on gas pressure, flame rectification, temperature rise, and air flow – HEATING 101. So, why did I take the time to write about basics?
If working in this industry for 48+ years, and the last 23+ years trying to help techs solve problems, has taught me anything it is the fact that we all forget to look at the basics. Because systems now have all sort of solid state controls (both commercially and residentially) and have communicating capabilities that can be accessed on “smart phones” and over the internet, we automatically ASSUME the worse possible scenario. How many times have I written about boards being changed that were not bad in the first place? About all sort of parts being replaced that were still good? Why did these things happen?
Even though all these new controls do allow a lot more capabilities with today’s equipment, the basics of heating have not changed since the day of the cave man. That’s right – you just need to think about it.
I was taught that the basics are:
- you need a fuel — That could be dinosaur dung, wood, coal, oil, or gas.
- you need a way of delivering that fuel – go and pick up the dung, cut down a tree and drag it back home, have coal delivered, have your oil tank filled up, have you propane tank filled up, have a gas pipe into your home.
- you need a way to ignite that fuel to get some heat out of it. — Cave men had to wait for lightning to hit something and start a fire. Then they had to get that fire, bring it back home and hope they don’t let it go out or they have to wait for the next lightning strike. Then banging rocks together to make sparks were found to be able to start a fire and that became more sophisticated with flint & steel. Then the stick and bow created heat that could ignite moss and tinder. Then matches were developed. Of course today we had spark ignition on oil burners and on gas products, but they were “noisy” (tick, tick, tick, etc), so the quiet hot surface ignition was developed.
- Now that you have fire – you need a way to contain it, vent it, and make use of it. How many caves were soot covered? How many huts burned down. How many CASTLES burned down that were not under siege :>)? How many buildings burned down because the fire was not “contained”? How many people died from CO poisoning? Then the FIRE PLACE and chimney were invented to help correct this but you still needed multiple fire places to heat the entire building. This then put a burden on the 1st 3 basics of FUEL.
- Of course, one of the last basics is making better use of the heat produced and delivering that heat as efficiently as possible and that JUST starts to get us to modern systems and better diagnostics.
If you look back into history, the first use of delivering the heat efficiently, containing the fuel, delivering the fuel all came about with the introduction of the STEAM boiler —- LATE 19th — EARLY 20TH CENTURY! The boiler provided a way to contain the fuel, vent the products of combustion up a chimney, better fuel “delivery” with the introduction of the STOKER to feed coal into the combustion chamber, but it still had to be hand lit and maintenance was high. But heat could be delivered to large ares via piping and radiators, thus bringing warmth without the “fire” to individual rooms or areas and getting the fuel to those areas also. THIS WAS THE FIRST MAJOR IMPROVEMENT SINCE CAVEMEN, FIRE PITS/RINGS, MIDIEVAL FIRE PLACES, AND CHOPPING WOOD AND HAULING WHATEVER SO YOU COULD LIGHT IT AND HAVE IT PRODUCE HEAT TO AN AREA.. All thanks to the Industrial Revolution and the invention of the steam engine.
But, this now brought new problems in making use of it. Because steam pressure has never had a vessel produced that can fully contain its potential — building were BLOWING UP! Another problem was the areas closest to the central heating plant would overheat. Now we get into the basic — controlling it and making use of it. IT IS THE DAWN OF CONTROLS AND CONTROL SYSTEMS.
Of course, by today’s standards, these were pretty crude controls but they did the job. Pressure controls to lower the draft in the coal combustion chamber – not electric –pressure moved an arm that was attached to a chain that allowed a damper to open and close based on pressure which let the fire in the chamber get hotter or cooler, controlling the pressure. If that did not work, then pressure relief valves. Of course the thermostat to help control areas – also non-electric but a bi-metal radiator valve. All may have been crude but they did the job. Almost all of these innovations were only for commercial spaces and not residential. Most homes were heated by “pot belly” stoves that burned wood or coal and usually had 1 per floor (or one on the main floor with a ceiling/floor grill between floors since heat rises or they still used fire places, or both. Residential central heating really did not come about until after WWII.
So now we have the post war housing boom. Coal and oil are the primary heating fuels. Stoker and controls are better,. The oil burner is introduced and new electric controls are developed so they operate safe. People are still afraid of GAS. Because homes are smaller, boilers are smaller and now use “hot water” instead of steam and rely on gravity (no pump) for circulation.This also brings the introduction of “gravity” air furnaces. These are built for coal and may have a stoker to a coal bin. The huge “octopus” ducts bring the heat to each room. These are still coal-fired or eventually converted to oil. But the newer oil furnaces, because they require electricity for the burner and ignition, are developed with blowers to create a more efficient delivery of the heat and small duct work can be used. Of course – new controls — stack switches, fan and limit controls.
Then in the late 1970’s early 1980’s there was an oil embargo and this is when Natural Gas became the choice for heating in urban areas. or where rural gas lines were available. Still basic control, bi-metal fan and limits, thermocouples, standing pilot light to light the main burner, belt driven blowers and a thermostat to turn it off and on — all electro-mechanical controls.
Today’s modern controls first get their start in the commercial space. Spark ignition, flame rectification, Variable speed ECM motors, solid state controls are only part of residential heating since the mid to late 1980’s – a little over 30 years ago.
Which now brings me back to where I started. History is there for a couple of purposes, to help us learn from our past mistakes and to show us how to make progress happen. YES — there is that word LEARN which I have always preached. But we always need to remember the BASICS which is why I write about them. Yes, we need to know and understand all the new controls systems out there and that takes even more LEARNING. But at the same time, we can NEVER overlook the basics. All the new controls do is make the equipment SAFER and more efficient. The basic principles still have not changed, only how we control it.
How many times have you heard that most problems (~97%) are usually something simple (basics), and the last ~3% are the “toughy” or a manufacturer defect. It is back to the K.I.S.S. PRINCIPLE — Keep It Simple Service-tech. Always approach a job with an open mind. If you approach a job with a preconceived idea – you usually make a misdiagnosis and then have to go back to the basics anyways..
This is the last post for 2014. Next year, I will be continuing with the basics and some more thoughts on that subject. I have also had a request to dwell a little on “heat pump defrost systems” and will probably have something on that subject. Suggestions are still welcome.
WISHING EVERYONE– HEALTH AND HAPPINESS IN THE NEW YEAR!