Tamarack Industries Thawzall HEATZONE TCH250, Руководство оператора

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14
How It Works
Boiler
Level
switch
Supply
manifold
Return
manifold
On-board
Diesel Tank
Flue
exhaust
TCH 250 – DIESEL
Supply
Temp
sensor
Thermostat
Safety
Thermostat
Circulating
pump
The Thawzall TCH250 is designed to heat a propylene glycol water solution which is then used for
ground thawing, concrete curing or space heating. The glycol solution is pumped into the onboard
boiler by use of a 1/2hp centrifugal pump, where it is heated and sent out to a distribution manifold
for use in the field. This solution is returned from the field into the return manifold and back into the
boiler for reheating. An electronically controlled three way valve adjusts the amount of return cool-
ant being directed into the, boiler depending on the set temperature requested at the controller.
(Operator selected)
The TCH250 is a closed loop system where the glycol/water solution is always stored within the
boiler and the field hoses.
A reservoir tank which contains about 12 gallons of the glycol/water solution is also found on
board. The solution in this tank can be used to pressurize the closed loop system in the event of
pressure loss. A pressure loss can occur from a leak in the system or if the system contained air
and it was evacuated through the use of the auto bleeders. This pressurization is accomplished
through the use of a pump found inline to the reservoir.
The control panel is located at the right rear side of the unit. All operations are controlled from here
including selection of input power preference as well as burner and reel control. The operator can
set the required temperature via the HMI (Human Machine Interface). The HMI will also display all
the return temperature being read at the manifold so all 5 zone temperatures can be monitored.
Safeties
The unit has a PRV valve which will release excess pressure back into the reservoir in the event of
over pressurization. Also found on the top of the water jacket on the boiler is a low glycol shutdown
safety. This safety will shut down the boiler is the case of low glycol in the system or excess air in
the system. The TCH250 comes with a shutdown thermostat located directly on the boiler in the
event of an over temperature condition within the boiler