Author Topic: More Help for those who need it :)  (Read 1706 times)

Offline Icehouse

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More Help for those who need it :)
« on: January 30, 2012, 10:45:18 AM »
Common Oil Furnaces Troubleshooting Tips Checking your Oil Furnace Fuel Supply
 
  • First things first with all Oil Furnaces, have you checked to be sure you have fuel in the fuel oil storage tank. You need to make sure as this is a more common mistake.
  • Once you are sure you have fuel in the tank make sure the fuel line is not leaking anywhere, look for stains where the fuel has bee leaking, you should smell it as a strong odor if the leak is fresh. Leaks in the fuel line can cause air to get into the system and the fuel pump can lose prime and stop pumping oil.

Checking your Oil Furnace Control Thermostat


 
  • Is the thermostat's system selector switch in the "heat" position?
  • Is the thermostat's temperature set point at least three degrees higher than the temperature inside?
  • Is your thermostat electronic? Some electronic  thermostats operate from batteries and if they are okay the LCD display should be visible. Many times if the LED display is not visible this may also indicated that the power to the furnace is off (see below). If you think you have a thermostat that runs off of batteries you can usually change the batteries by carefully removing the thermostat from the wall mount as the batteries are generally located inside the thermostat.
  • You can test your thermostat if it has switch or button to control the indoor blower or fan, switch it to "on." Listen to hear if the blower or fan comes on. If you do not hear any fan or there is no air coming from your supply registers then check to be sure the power is on at the indoor unit (oil furnace). (see below) If the power is on and you do not hear the fan running this may indicate that you have a bad capacitor, blower motor or other common issue.
Checking your Power or Electrical

 
  • Your heating system may have a power switch at the oil furnace or indoor unit. In most homes in the Treasure Valley area the power switch looks just like a regular light switch and is generally located right on or beside the oil furnace or indoor unit. Make sure the switch is on.
  • Most oil furnace heating systems have another hidden switch that shuts off your unit if the front service panel or blower door is removed. Make sure all the service panels are on and secure.If the fan still does not operate check to see if any electrical panel circuit breakers are tripped. Usually if a circuit breaker has tripped it will not be fully in the "on" position. To reset the circuit breaker turn it off all the way and then back on.

Checking your Oil Furnace Sequence and Ignition

 
  • The Oil furnace has what is called the combustion blower and motor, do not confuse this with the blower that moves the air in the house. The combustion blower is usually part of the burner assembly on the front of the unit.
  • Immediately upon any call for heat this combustion blower will run, the oil pump is normally also connected to the same motor as the combustion blower motor and the fuel pump will run with the combustion blower so if you have a blower operating you normally have a fuel pump operating also.
  • Nearly all oil furnaces have an intermittent spark ignition and no pilot light so do not look for a pilot light. Once the combustion blower has run for a few seconds to clear the combustion chamber you can usually hear the system open the oil supply and try to light the flame with a spark from the spark igniters or probes. (makes several clicking sounds) Normally it will try this for a few seconds and if no flame is present it will shut down at this point and require a reset.
  • Once the flame lights the safety system or control board confirms the flame and monitors the flame. The blower that circulates air through the home usually starts and runs based on the temperature in the heat exchanger box, no heat or flame and the blower will not run
NATE, NCCER, PHCC,HVAC Certified Instructor
Member RSES, US Army Refrigeration Specialist(Retired), Former Refrigeration Teacher NYC Board of Ed.
a tragedy has happen to me : http://web.me.com/zenzoidman/Bobice/

Offline Icehouse

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    • hvacbob
Re: More Help for those who need it :)
« Reply #1 on: January 30, 2012, 10:50:02 AM »
Heating Hot Water Boilers Tips for Troubleshooting
Checking your Control Thermostat

    * Is the thermostat's system selector switch in the "heat" position if applicable?
    * Is the thermostat's temperature set point at least three degrees higher than the temperature inside?
    * Is your thermostat electronic? Some electronic thermostats operate from batteries and if they are okay the LCD display should be visible. Many times if the LED display is not visible this may also indicated that the power to the boiler is off (see below). If you think you have a thermostat that runs off of batteries you can usually change the batteries by carefully removing the thermostat from the wall mount as the batteries are generally located inside the thermostat.
   

Checking your Power or Electrical


    * Your boiler system may have a power switch. In most homes in the power switch looks just like a regular light switch or is a control switch on the boiler itself and is generally located right on or beside the boiler. Make sure the switch is on as indicated above.
    * Some boiler systems have another hidden switch that shuts off your boiler if the front service panel. Make sure all the service panels are on and secure.
   * If the boiler still does not operate check to see if any electrical panel circuit breakers are tripped. Usually if a circuit breaker has tripped it will not be fully in the "on" position. To reset the circuit breaker turn it off all the way and then back on.
   * Almost all heating hot water boilers have circulating pump, the pump is normally powered by the same circuit as the boiler, check to make sure this pump turns on upon a call for heat as this is the first thing that must happen before the boiler can operate.



Checking your Gas Boiler Ignition


   * If your boiler system is an older gas boiler (usually 10 plus years old) it may have a standing pilot light like a water heater, if this is the case carefully follow the instructions on the boiler to light the pilot.
    * Some models have an intermittent pilot light and you can usually hear the system try to light the pilot flame with a spark (makes several clicking sounds).
    * Most newer boiler systems these days have a hot surface ignitor which will glow red hot when the system is trying to light the main burner flames. The hot surface ignitor looks like a very small electric oven heating element and they are fragile and easily crack and break over time.

In all cases if your boiler fails to light the pilot, the pilot will not stay lit or the main burner flame does not ignite you should shut off your boiler and contact a qualified service company to inspect your system. If you smell gas open an outside door and/or windows and exit the area immediately.



Other Common Gas Boiler Issues


    * Is the boiler full of water, many boilers have safety switches that will turn off the boiler if it is low on water
NATE, NCCER, PHCC,HVAC Certified Instructor
Member RSES, US Army Refrigeration Specialist(Retired), Former Refrigeration Teacher NYC Board of Ed.
a tragedy has happen to me : http://web.me.com/zenzoidman/Bobice/

Offline Icehouse

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    • hvacbob
Re: More Help for those who need it :)
« Reply #2 on: January 30, 2012, 10:56:34 AM »
Heat Pump Troubleshooting Tips Checking your Heat Pump Control Thermostat

    * Is the thermostat's system selector switch in the "heat" position?
    * Is the thermostat's temperature set point at least three degrees higher than the temperature inside?
    * You can check your systems back up heat source by switching to emergency heat on the heat pump thermostat, this should override the outdoor unit from running and run on the back source electric heat.
    * Is your thermostat is electronic? Some electronic  thermostats operate from batteries and if they okay the LCD display should be visible. Many times if the LED display is not visible this may also indicated that the power to the electric furnace  or air handler is off (see below). If you think you have a thermostat that runs off of batteries you can usually change the batteries by carefully removing the thermostat from the wall mount as the batteries are generally located inside the thermostat.
    * You can test your heat pump thermostat  if it has switch or button to control the indoor blower or fan, switch it to "on." Listen to hear if the blower or fan comes on. If you do not hear any fan or there is no air coming from your supply registers then check to be sure the power is on at the indoor unit. (see below) If the power is on and you do not hear the fan running this may indicate that you have a bad capacitor, blower motor or other common control issue.
 

Checking your Power or Electrical

     * Your heat pump system may have a power switch at the indoor unit. In most homes in the Treasure Valley area the power switch looks just like a regular light switch and is generally located right on or beside the indoor unit. Make sure the switch is on as indicated above.
    * Many heat pump systems  have another hidden switch that shuts off your unit if the front service panel or blower door is removed. Make sure all the service panels are on and secure.
    * If the fan still does not operate check to see if any electrical panel circuit breakers are tripped. Usually if a circuit breaker has tripped it will not be fully in the "on" position. To reset the circuit breaker turn it off all the way and then back on.

Checking your outdoor unit

     * If you have a heat pump and you can hear the outdoor unit running but cold air is blowing in your home you should wait a few minutes to see if the system starts heating again. Heat pumps will typically build up ice on the outdoor unit and in order for the system to continue working properly this ice must be removed. The heat pump will go through a defrost cycle  to melt the ice that usually will last just a few minutes. Sometimes the defrost timer or controller fails and the unit either builds up ice to the point that it will not work or it gets stuck in this defrost mode. Check to see if you have ice build up on the outdoor unit if you do then you should call a qualified service company.



Back Up Emergency Heat

     * Most heat pump systems  have back up or emergency heat, this back up heat will usually come on when it gets too cold outside or too cold in your home, in many cases you can manually turn on the emergency back up heat at the thermostat with a selector switch or button, this will get you some heat while you wait for repairs to your heat pump
NATE, NCCER, PHCC,HVAC Certified Instructor
Member RSES, US Army Refrigeration Specialist(Retired), Former Refrigeration Teacher NYC Board of Ed.
a tragedy has happen to me : http://web.me.com/zenzoidman/Bobice/

Offline Icehouse

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  • Member Since: Oct 2008
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    • hvacbob
Re: More Help for those who need it :)
« Reply #3 on: January 31, 2012, 10:52:21 AM »
A very common gas furnace problem It's 11:00 PM and 15 Degrees outside and your furnace is acting up... That's just great! you say to yourself. Now I have to call an HVAC Contractor and pay hundreds of dollars extra to get my furnace fixed or freeze the rest of the night... Wonderful!

Well sometimes the most common gas furnace issue does not have to cost anything to fix and you would be surprised at just how easy it actually is to resolve the problem. What are we talking about here? The flame sensor.

 The flame sensor is usually a small metal cylinder about half the width of a pencil and an inch or two long and will have a long wire or metal tube connected to it. The sensor will sit or be positioned directly in the flame itself... when it is lit of course and the sensor tells the control board that you have an active burner or pilot flame  and when it is not working properly it will cause a nuisance by allowing the furnace to run sometimes, sometimes for short periods and sometimes not at all.

 
The problem is very common and can sometimes be rectified by simply cleaning the little metal probe that sticks in the flame. These metal probes are prone to getting caked with a deposit, usually an off white or brownish rusty color. This cake of crud prevents the sensor from heating up properly and provides the control board false readings for the flame condition.


 
So if you are stuck in the middle of the night with the gas furnace symptoms described above you can try this simple measure and see if it works. Simply clean the metal cylinder with fine sandpaper or emery cloth, you can also use steel wool or other fine abrasive materials. Just clean it enough to get that caked crud off... just be careful not to scratch off too much of the metal as that can ruin the sensor.


This works nine times out of ten at least one time and this same procedure can be used on many gas water heaters  when the pilot light that will not stay lit as it is pretty much usually the same problem. If the sensor is clean and the gas furnace or gas water heater still does not work then it is more than likely time to call for service.
NATE, NCCER, PHCC,HVAC Certified Instructor
Member RSES, US Army Refrigeration Specialist(Retired), Former Refrigeration Teacher NYC Board of Ed.
a tragedy has happen to me : http://web.me.com/zenzoidman/Bobice/