How does ThermGuard increase the efficiency of my wood stove, gas stove or fireplace insert in my home with a furnace?

By turning on your furnace fan periodically during the day and night, ThermGuard circulates the warm air from the room with the stove to other parts of the house.  Your home gets heated more evenly and you don't have one room too hot while the others are too cool.  By circulating the warm air into rooms that may be closed off from the main area, such as unused bedrooms, you prevent freezing conditions that may exist on bitter cold days.


How does ThermGuard prevent my radiant or baseboard heating pipes from freezing?

By circulating a small amount of hot water periodically during the day and night, ThermGuard never gives your heating pipes a change to freeze.  ThermGuard  acts as a timer to turn on your heating system regardless of what temperature the thermostat reads.  This is particularly useful when an alternative heat source is used in your home such as a wood or gas stove/fireplace insert or you have rooms in your home that you close off from your standard heat source.


How does ThermGuard help lower my heating bill?

In homes with furnaces, ThermGuard will heat your home more evenly with your alternative heat source and thus lower your heating bill when more of the heat comes from your stove.  ThermGuard can also help to lower your heating bill by allowing the temperature in unused rooms of your home to be reduced. 

For homes with hot-water heat and an alternative heat source, the thermostat can be turned very low or off altogether and ThermGuard will circulate hot water through your heating pipes periodically to keep them from freezing while the stove warms the home.  When a home is vacant for a period, such as a vacation home, the thermostat can be set to a much lower point since ThermGuard will keep the heating pipes from freezing.  The internal temperature of the home just needs to be high enough to keep the internal hot and cold water pipes from freezing.


Is ThermGuard difficult to install?

ThermGuard simple attaches to the existing thermostat connection points.  There are two wires which are connected to the same wires running to your thermostat.  In most cases, this involves loosening two screws on your thermostat, inserting ThermGuard’s wires and tightening the screws.  It typically takes less than 5 minutes.


Is ThermGuard difficult to program?

ThermGuard uses a very simple single button programming method.  The button is held down for 3 seconds to enter into programming mode.  The button is then pressed for the number of hours to wait before turning on your fan or heating system.  Once the hours are entered, the button is pressed to indicate the number of minutes to run.  ThermGuard uses two LEDs to indicate when to enter hours or when to enter minutes.


I have more than one temperature zone in my hot-water heated home, how many ThermGuard units do I need?

One ThermGuard unit should be used for each zone which has heating pipes which extend to the outside walls of your home.  Certainly, one should be used for any heating pipes that run through garages or attics.


Should I turn off my ThermGuard during the summer months?

In a home with a furnace, ThermGuard can be switched off.

In a home with hot-water heat, the interval and duration should be adjusted to run your heating system for a couple of minutes each day.  This will prevent your valves and pumps from seizing, keep your seals from drying out and also prevent air bubbles from accumulating in zones.  Air bubbles can cause your pumps to malfunction when your system switches on for the winter.


Do I have to install ThermGuard under my thermostat?

No, ThermGuard can be installed in the mechanical room of your home where the lines are run from the 24V transformer to your thermostat.


Will ThermGuard work with my thermostat?

ThermGuard will work with most thermostats including standard mercury switch thermostats and newer programmable thermostats.


Will ThermGuard work with my heating system?

ThermGuard will work with all types of low-voltage (24VAC) furnace and hot-water heating systems.  ThermGuard supports hot-water heating systems that have zone controllers such as Taco or Eire.  It will also work with systems that have the zone valves controlled directly by the thermostat.


What does a Green LED Flash every few seconds mean?

ThermGuard flashes the Green LED every few seconds to indicate that ThermGuard is awake and timing the Interval period. It is a heartbeat to show you that ThermGuard is working properly.


What does ThermGuard do when the thermostat calls for heat in my boiler heated home?

ThermGuard stops all operation and LED flashing when your thermostat calls for heat in your boiler heated home. ThermGuard restarts the interval timing when the thermostat stops calling for heat. This way ThermGuard saves fuel by not turning on the boiler if has just finished heating the zone.

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Last modified: 01/21/14