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TES Troubleshooting

9 – OVERHEATING

Do not turn the pump switch ON unless the By-pass valve is open or you have two or more TEX boxes and hoses connected to the TES unit.

There are only a couple of gallons of fluid in the TES boiler and during testing this fluid will heat up quickly and has no way to cool down. This can cause damage to the boiler and can create a dangerous condition.

For safety reasons we recommend that you should always have at least two TEX boxes with air movers connected to the TES unit when attempting to ignite the TES burner.

The perception of overheating may be in the reading of the gauges of the machine or the boiler may actually be getting too hot.We have to determine three things.

1. Are the gauges reading properly?

2. Are the temperature controls working properly?

3. Is the fluid circulating properly?

During operation, the TES inlet temperature gauge should be around 200˚F and the TES outlet temperature gauge should be reading around 230˚F.

(The gauges are not very accurate. Allow for a 20-30 degree difference.)

If the gauge temperature readings are too low – Proceed to Step #1
If the gauge temperature readings are fairly accurate – Proceed to Step #2
If the gauge temperature readings are too high – Proceed to Step #1
Not sure – Proceed to Step #1.

Step #1 Temperature Gauges

If the temperature gauges are distorted or show signs of heat damage – Replace the gauges and proceed to Step #2.
If the temperature gauges do not show signs of heat damage – Continue with testing.

Check the temperature gauge readings before turning the TES unit ON. If the TES unit has been OFF and has cooled to room temperature the reading of both gauges should be below the 100˚F mark on the gauges (Unless the room temperature is above 100˚F). If the TES unit has been running and is still warm, you should keep the TEX boxes connected, the air movers running and the pump running until the unit has cooled.

If both the temperature gauges read the approximate room temperature – Continue with testing.
If one or both of the temperature gauges read a temperature much higher than the room temperature – Replace the gauges as needed and proceed to Step #2.

With two or more TEX boxes connected, open the By-pass valve and turn the pump ON. Turn the heater switch ON and switch ON & OFF as needed to start the burner.

If the burner does not ignite – Go to TES 5.
If the burner lights – Run the unit and allow the boiler to heat up. You can feel the quick connects and hoses to determine if the unit is getting hot. You can also use a Infrared Thermometer to check the hose temperature. Are the hoses getting hotter?
No – Proceed to Step #2.
Yes - While the TES unit is operating check the reading of the temperature gauges. Are the temperature gauges indicating the same temperature rise that you are finding in the hoses and quick connects?
Yes – Proceed to Step #2
No – Replace the temperature gauges and proceed to Step #2

Step #2Temperature Controls

Check the setting of the Operator Control. It should be set at 200˚F. Check the setting of the Hi-Limit Control. It should be set at 230˚F.

With two or more TEX boxes connected, open the By-pass valve and turn the pump ON. Turn the heater switch ON and switch ON & OFF as needed to start the burner.

If the burner does not ignite – Go to TES 5.
If the burner lights – Run the unit and allow the boiler to heat up. You can feel the quick connects and hoses to determine if the unit is getting hot. You can also use a Infrared Thermometer to check the hose temperature. Are the hoses getting hotter?
No – Go to TES 8.
Yes - While the TES unit is operating check the reading of the temperature gauges. Are the temperature gauges indicating the same temperature rise that you are finding in the hoses and quick connects?
Yes – Continue with testing.
No – Replace the temperature gauges and continue with testing.

As the TES unit heats up and the Inlet Temperature Gauge approaches 160 to 180˚F, turn the Operator control down until the Operator Light turns OFF. If the unit is heating up too fast during testing, add more TEX boxes, turn the air movers on the high speed setting and close the by-pass valve to draw more heat from the system. Note the temperature reading of the Inlet Temperature Gauge when the light goes out.Return the Operator control to its 200˚F setting.

(The gauges are not very accurate. Allow for a 20-30 degree difference.)

If the TES unit does not get hot – Go to TES 8.
If the Operator Light does not turn OFF – Replace the Operator Control and continue with testing.
If the Operator Light turns off when the temperature setting is approximately the same as the Inlet gauge reading – Continue with testing.
If the Operator Light turns off but the temperature setting at which it turns off is more than 20-30 degrees different than the gauge reading – Adjust or replace the Operator Control and continue with testing. (There is only a small mount of adjustment that can be made to the control.)

When the Operator Light turns off, does the burner turn OFF?

Yes – Continue with testing.
No – Proceed to Step #2A.

As the TES unit heats up and the Outlet Temperature Gauge approaches 160 to 180˚F, turn the Hi-Limit control down until the Hi-Limit Light turns off. Note the temperature reading of the Outlet Temperature Gauge when the light goes out.

(The gauges are not very accurate. Allow for a 20-30 degree difference.)

If the TES unit does not get hot – Go to TES 8.
If the Hi-Limit Light does not turn OFF – Replace the Hi-Limit Control and continue with testing.
If the Hi-Limit Light turns off when the temperature setting is approximately the same as the Outlet gauge reading – Continue with testing.
If the Hi-Limit light turns off but the temperature setting at which it turns off is more than 20-30 degrees different than the gauge reading – Replace the Hi-Limit Control and continue with testing.

When the Hi-Limit Light turns off, does the burner turn OFF?

Yes – Proceed to Step #2B.
No – Proceed to Step #2A.

Step #2A

If the incoming gas pressure is too high the gas valve may not be able to stop the flow.

An incoming manifold pressure of 12-14” of water column must be maintained for proper operation of the gas valve. Before beginning to test the pressure, make sure the propane tank valves are closed. Connect a manometer to the inlet pressure tap port. Open the propane tank valves and check the pressure.

If the pressure is in the range of 12-14” WC – Continue with testing.
If the pressure is less than 12” WC or more than 14” WC – Adjust the regulator to set the pressure in the correct range.
If the pressure can be adjusted and set in the range of 12-14” WC – Continue with testing.
If the pressure cannot be adjusted to the correct range – Replace the regulator and adjust the pressure and continue with testing. If you have already replaced the regulator and cannot adjust the pressure to the proper range contact your nearest distributor for advice or assistance.

Check the setting of the Operator Control. It should be set at 200˚F. Check the setting of the Hi-Limit Control. It should be set at 230˚F.

With two or more TEX boxes connected, open the By-pass valve and turn the pump ON. Turn the heater switch ON and switch ON & OFF as needed to start the burner.

If the burner does not ignite – Go to TES 5.
If the burner lights – Run the unit and allow the boiler to heat up. You can feel the quick connects and hoses to determine if the unit is getting hot. You can also use a Infrared Thermometer to check the hose temperature. Are the hoses getting hotter?
No – Go to TES 8.
Yes - As the TES unit heats up and the Inlet Temperature Gauge approaches 160 to 180˚F, turn the Operator control down until the Operator Light turns OFF. Does the burner turn OFF?
Yes – Continue with testing.
No – Disconnect the brown wire from the gas valve.
If the burner turns off – Replace the burner ignition control and return to Step #2. If you have already replaced the burner ignition control there is wiring problem that is providing power to the blue wire on terminal #6 of the burner ignition control even when the operator control is breaking the circuit. Use the wiring diagram to check the wires and repair as needed or contact your nearest service center for advice or assistance.
If the burner does not turn off – Replace the Gas Valve and return to Step #2.

Turn the Hi-Limit control down until the Hi-Limit Light turns OFF. Does the burner turn OFF?

Yes – Return to Step #2.
No – Disconnect the brown wire from the gas valve.
If the burner turns off – Replace the burner ignition control and return to Step #2. If you have already replaced the burner ignition control there is wiring problem that is providing power to the blue wire on terminal #6 of the burner ignition control even when the operator control is breaking the circuit. Use the wiring diagram to check the wires and repair as needed or contact your nearest service center for advice or assistance.
If the burner does not turn off – Replace the Gas Valve and return to Step #2.

Step #2B

Return the Operator Control setting to 200˚F and the Hi-Limit Control to 230˚F.

Allow the TES unit to continue heating up. When the Inlet Temperature Gauge reaches 200˚F, the OPERATOR Light should turn off. When the Outlet Temperature Gauge reaches 230˚F the HI-LIMIT light should turn off. If the flow rate is high, the system may not get up to 230˚F during normal operation. If the Operator control is turning OFF at the correct temperature and the Hi-Limit turns off when it is turned down a little, matching the outlet temperature gauge reading – Proceed to Step #3

If the TES unit does not heat up to 200˚F – Go to TES 8.
If the OPERATOR Light and HI-LIMIT Light turn off at the right temperature – Proceed to Step #3.
If the Operator Light does not turn OFF or turns off at too high of temperature – Adjust or replace the Operator Control and return to Step #2.
If the HI-LIMIT Light does not turn OFF or turns off at too high of temperature – Adjust or replace the Hi-Limit Control and return to Step #2.

Step #3By-Pass Valve

If the by-pass valve is open too much, most of the hot fluid just makes a loop from the outlet side to the inlet side of the heater and the flow to the TEX boxes is not enough to cool the heater, causing the overheating condition.

To test the operation of the By-pass valve the heater does not need to be ignited so the propane tank valves should be closed. Make sure the Operator control is turned up to 200˚F and the Hi-Limit control is turned up to 230˚F. Do not have any hoses or TEX boxes connected to the TES unit.

Open the By-Pass valve completely by turning the valve handle counter-clockwise. Turn the pump ON and turn the heater switch ON. The first four lights should all be ON. The last light, the MAIN GAS light will remain OFF.

If all four lights are ON – Continue with testing.
If the POWER light is OFF – Go to TES 4.
If the OPERATOR light is OFF – Go to TES 7.
If the HI-LIMIT light is OFF – Go to TES 6.
If the LOW FLOW light is OFF – Go to TES 1.

Turn the pump switch OFF. Does the LOW FLOW light turn OFF?

Yes – Continue with testing.
No – There is a red wire from the Flow Switch that connects to the terminal block. Disconnect this red wire from the terminal block. It is on terminal #5 on a 10 terminal block or terminal #3 of the 8 terminal block. Does the LOW FLOW light turn OFF?
Yes – Replace the Flow Switch and return to the beginning of Step #3.
No – There is power coming from another source to this terminal and through the blue wire to the LOW FLOW light. Check and repair the wiring as needed and return to the beginning of Step #3 or contact your nearest service center for advice or assistance.

Slowly close the by-pass valve until the LOW FLOW light goes out. Once the LOW FLOW light turns OFF or if the valve is closed completely, immediately turn the pump switch OFF.

If the LOW FLOW light turns off before the valve is closed – Proceed to Step #4.
If the LOW FLOW light does not turn OFF- Replace the By-Pass valve and return to the beginning of Step #3 or contact your nearest service center for advice or assistance.

Step #4 Hoses and TEX boxes

A restriction of the flow through the hoses, Splitters or TEX boxes will require that the By-pass valve be opened too much during operation.

The splitters can be tested with a water source and quick connect adapters. Test each splitter for unrestricted flow and remove and clean or replace the quick connects as needed to assure free flow through each splitter. Use air to blow the water out of the splitter after cleaning.

Then connect the hoses one section at a time in a loop from the outlet quick connect to the external filter canister and to the inlet quick connect. With the by-pass valve closed, there should be enough flow through each hose section to keep the LOW FLOW light ON. If the LOW FLOW light turns OFF, use water to flush out the solution hose and replace the quick connects as needed. After cleaning use air to blow out the water and reconnect the hose to the TES unit to refill the hose with fluid. You will have to add fluid to the reservoir as the air is removed from the system and fluid is drawn out to fill the hose.

Now connect all the hoses and TEX boxes to the TES unit. Turn the air movers in each TEX box to the low speed setting. With four or five TEX boxes connected, open the By-pass valve and turn the pump ON. Turn the heater switch ON and switch ON & OFF as needed to start the burner.

If the burner does not ignite – Go to TES 5.
If the burner lights – Run the unit and allow the boiler to heat up. You can check the gauges and feel the quick connects and hoses to determine if the unit is getting hot. Is the unit getting hot?
No – Go to TES 8.
Yes – Now slowly close the by-pass valve. With four or five TEX boxes connected you should be able to close the valve completely and the LOW FLOW light should stay on.
If the LOW FLOW light stays on with the valve closed – Continue with testing.
If the LOW FLOW light turns OFF before the valve is closed – There may be a restriction in one or more of the TEX boxes. Remove the male quick connect from each TEX box and connect a water hose to the female quick connect to flush water through the TEX box to remove debris. Clean out or replace the quick connects and coil as needed to remove the restriction and return to the beginning of Step #4. If you have already checked the TEX boxes and there are no restrictions you may need to rebuild the solution pump. Contact your nearest service center for advice or assistance.

With the by-pass valve closed and the heater up to temperature. Test the air inlet and outlet temperature at each TEX box. Each box should have an outlet temperature 30-40˚F higher than the inlet air temperature.

If the air outlet temperature at all boxes meets or exceeds this temperature rise – Exit.

If the air outlet temperature at any box has a lower temperature rise - There may be a restriction in one or more of the TEX boxes. Remove the male quick connect from each TEX box and connect a water hose to the female quick connect to flush water through the TEX box to remove debris. Clean out or replace the quick connects and coil as needed to remove the restriction and return to the beginning of Step #4. If you have already checked the TEX boxes and there are no restrictions you may need to rebuild the solution pump. Contact your nearest service center for advice or assistance.

Revised: 06-13-08