Image of thermodisk fan control dial settings. These are
more common on older furnaces than new ones that will use a control module
to control the fan.
Bottom image of fan thermostat thermo-disk.
Used on furnaces where there is not enough room
for a conventional probe
type limit control.
Package that thermostat came in. This one was purchased
from Aireco in Maryland, you can also get them from Grainger or Johnstone
Supply. For a list of supply houses click
Images of electric heat sequencers.
Carrier part number HN67QC 005 Ths one has two sets of
switches (1 to 2, 3 to 4) and two timing functions to minimize use of the
second heating element.
Blower: usually a squirrel cage centrifugal air moving device. Will move
large volumes of air relatively quiet. Will use less energy with more back
Fan: a paddle type air moving device used where noise is not a major consideration.
Will use more energy with more back pressure.
Combustion blower: A blower used on high efficiency furnaces or oil burners
to move combustion air. usually 1/20 to 1/6 horsepower.
OEM: Original equipment manufacturer.
Horsepower: 746 watts
KW Kilowatt (1000 watts) or 3400 BTUs per hour
RPM: revolutions per minute.
Service factor: the extent to which a motor can be safely overloaded beyond
its name plate ratting without over heating.
Air over horsepower: The rating of a motor assuming air flow through the
windings usually as a result of the air moving device.
SAE: Society of Automotive Engineers.
Ton 12,000 BTUs per hour of heating or cooling
This page will be updated soon
Good Luck Scott
If your heat pump forms
ice outside in the heat mode click
If your air conditioner or heat pump ices
in the cooling mode click
If you have
water leaking problems with your air conditioner
click here to solve it.
To ask us about heat pump problems click
here. To ask us about other heating system problems click
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Any other questions feel free to contact us by
any of the means below. good luck Scott.
Written By: Scott
Meenen N3SJH of: G&S MECHANICAL SERVICES. Specializing in Mechanical, Controls
and Electrical Modifications Of
Heating, Air-conditioning, Refrigeration,
Ice Production and Food preservation.
Anything having to do with Heat and Energy.
Serving MD, DC, and Northern
VA. Contact us by pager: 1-877-467-2914