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Original Question Sent To Tom Berry, The Furnace Man

Craig Anderson wrote:

I have a home in Colorado (cold winters and warm summers) which has propane heat and electric AC. The farm also has several oil and natural gas wells. 

The last owner piped the natural gas (petroleum engineer work) to the home and re-jetted the furnace for natural gas or propane when the well is shut in. Not the best way to go for safety but everyone does it around here since the natural gas is FREE.

I was thinking of a second approach - a natural gas heat pump/ air conditioning unit which sets AC style outside the house and uses the  heat exchanger in the existing duct work. This would be installed next to the original system. This has several advantages such as free natural gas and safety since well head gas will not enter the home. Also Air conditioning. Can you suggest outdoor heat pump or heat pump furnace combos that work in this climate? The original system can always help out if necessary.

I know many people including myself, who would love to be in your situation. If you have natural gas available, then by all means wear it out. Air to air heat pumps require electricity to operate.

When compared to the operating cost of natural gas, propane or oil a heat pump will be more cost effective to operate than fossil fuels in mild weather 35 degrees and above. When any fuel that you have to pay for is compared to one that you don't, you can't beat free. For your situation you have four ways to make cold.

1: Use a conventional air conditioner that is electrically operated 

2: Use a conventional air conditioner that has a belt drive (automotive) compressor and is driven by a natural gas engine.

3: Use an absorption type air conditioner that is fired by natural gas. Such as one made by Bryant, AB Electrolux, Norcold or Dometic (formerly Arkla).
Note: Absorption air conditioning still requires electricity to operate the pumps and blowers.

4: Use a conventional air conditioner powered by an engine driven generator that is fueled by natural gas. This is probably the cheapest to operate but not the most cost-effective if you weigh the wear and tear on the engine. 

Scott Meenen

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Humidifier Control: Subject: RE: Honeywell's home heating controls

You may want to look at the PC8900 Perfect Climate Comfort Center. This thermostat provides both furnace and humidifier control. The comfort center takes the outdoor temperature reading and calculates the dew point to help prevent humidity from accumulating on the windows. If you would like some information sent to you on this product, please send us your mailing address. Could you pass the following question on to your home heating people: I've got a Honeywell thermostat for my furnace as well as a Honeywell control for my furnaces (add-on) humidifier. All home humidifier controls are set to a relative humidity based on the outside temp. Why can't I find a control that has an outside thermostat and sets it itself?? Why can't I find one unit that is both humidifier and furnace control...?? Thanks,
Art McEwen 

ANSWER: Sounds like you found it Art. I haven't used that piece of equipment so I can't comment on it. In the maritime Pacific Northwest we don't have a lot of use for humidifiers although I do suggest to folks that they add humidity to their home environment during the winter because houses get too dry. I don't know how much money that equipment costs but I could find out for anybody interested......... tom 

I believe that April Air has a control that will adjust with outside temperature. If you live in a location where the low winter temperature doesn't vary much from average. Then you can set your humidistat to about 40%. As long as you don't get any condensation on windows and walls you are probably Ok. But keep an eye out for dew.

While on the subject of humidifiers. I have found the best humidifier in the world bar none. Is the Humidifier 707. This unit mounts on the return duct. It works by sucking up the water, chewing it up into a fog and blowing it into the return duct. All the crap in the water gets trapped in the filter and gets thrown away with the filter. Or  gets washed out if you have a washable filter. There is no media pad to mess with and the average life expectancy is 20+ years. This type of humidifier works great with heat pumps and with large demand. Because they don't need hot air to work they will continue to dump moisture into the house whenever the fan is running.

Scott Meenen

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This Question originally sent by the G&S Mechanical
heating question fill out form.

                This Question relates to how the fan 
works on a forced air furnace.
When the thermostat temp gets low enough for the heater to come on, we
 can hear the burner ignite, but the fan does not come on.  This unit is
 also used for the A/C, so we know the blower works.
 What could be the problem? 

 Answer by Scott Meenen N3SJH
If this if a newer furnace it  uses an electronic timer to start the fan, if this is an older unit then it probably uses a thermostat in the plenum ( the heat exchanger) to start the fan.
Some furnaces have a combination of both.
 This thermostat is usually combined with the high limit that cuts off the burner in case of over heating. Some older furnaces may have the thermostatic fan control replaced with or backed up by a timer.
If the fan works by placing the fan switch on the thermostat in the fan on position (usually high speed) then you know that there is power to the fan motor, however most furnaces have multi speed fans and use the higher speeds for air-conditioning and the lower speeds for heating. If the fan is belt driven then the fan only runs at one speed for heating or cooling.
Good luck Scott.

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This furnace pilot question

was submitted on March 20th 2000

By Karen of Mt. Vernon Illinois.

My mobile home furnace won't stay lit. I had the pilot cleaned Sept. 99. It
  was working fine and it just went out. The flame goes out when I release
 the pilot knob. The flame acts like it may have air in the line, but the
  burners on my cooking stove are not affected. Do you have any ideas by
 what i've told you? 
   Please send advice if it's something I can do or do I  call a repairman.
       Karen Casteel

 On most all standing pilot systems the pilot heats a thermocouple (two dissimilar metals that generate electricity). This electricity holds open the valve
 that keeps the pilot burning. When the pilot goes out the thermocouple
 cools and shuts off the gas to the pilot and the main valve.
  If you have a "milli-volt system" then instead of a thermocouple you have a
 thermopile that generates about 1/2 a volt and electrically operates the main valve as well as the pilot valve.

  These thermocouples do fail and will cause the valve not to hold in or they may not stay in. They are also very cheap to replace. A thermopile is a little bit more expensive and the way to tell if your system has one is that there will not be a
 24 volt transformer to open the gas valve and a thermopile has wires and
 lugs on the wires, a thermocouple looks like a piece of capillary tubing
 that has threads that screw into the gas valve.
  If you need to replace your milli-volt gas valve I recommend that you install a
 conventional 24 volt gas valve that uses a transformer and a conventional
 thermocouple (standard 24 volt valves are less expensive and easier to find), unless of course your system doesn't have a 120 volt blower. 

    As for something that you as a home owner can do is to make sure that
 the thermocouple has not fallen out of the path of the pilot. 
  If you are mechanically inclined you can easily replace a thermocouple or
 thermopile with a little more difficulty. But I would seek professional help to replace a gas valve.
      To see images of gas valve systems click here
For a list of all files go to the sitemap

  Good luck. Scott N3SJH

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This Question originally sent by the G&S Mechanical
heating question fill out form.