1. DESCRIPTION OF STEAM GENERATOR
The Printed Circuit Assembly (the “PCA”) provides the basic functions necessary to produce steam. The PCA controls makeup water, provides a water level permissive for powering the elements and provides raw DC power for the system. The PCA also provides regulated non-interruptible low voltage VDC power for the T100 control and the temperature sensor. It also provides the interface circuitry between the control and the PCA. The T100 control provides the room temperature control loop, an adjustable bath timer and power switching for “soft steam”.
2. MAINTENANCE OF STEAM GENERATORS
3. REPAIR OF GENERATORS
A. ELEMENT REPLACEMENT:
Disconnect power from the unit. Drain the tank. Remove the front and HEATING ELEMENT ACCESS covers. Note the wire connections. (See diagrams 14 & 15) Remove the element wires. Using a hot water element socket, remove the element.
To install a new element, mount a new element gasket on the element. Clean the element port and add a light coat of Rectorseal No. 5 pipe thread compound to the threads. Insert and hand tighten the element-gasket combination. Notice the element end orientation as shown in diagram. Tighten the element until the orientation is the same as the diagram, ± 15°. The gasket should be set and tight but not deformed to a rounded or bulbous appearance. If the drain valve was removed reinstall it. Reconnect the wiring. Test the unit per SECTION 7: OPERATIONAL
B. PRINTED CIRCUIT REPLACEMENT:
Printed circuit assembly (PCA) removal and replacement must be performed in the following sequence, any other
method can damage the PCA. (See diagram 16-19)
Disconnect power from the unit. Note and tag the positions of all wires that plug into the printed circuit assembly mounted relays. Remove all the wires from the
relays. When removing these wires, pull on the connector, not the wire. Note the blue connected to the shortest of the triple pronged water level probe rods and
the black wire connected to the rod with black tubing. Disconnect all three wires from the water level probe. Remove PCA from all fi ve standoffs by pinching the
tops or removing the screws. When it is completely disconnected, it may be lifted out of the enclosure.
To install the board, reverse this procedure. The wire lugs must fi t tightly onto the relay tabs! Test the unit per SECTION 7: OPERATIONAL TEST.
C. WATER SOLENOID REPLACEMENT:
Disconnect power from the unit. Turn the water supply OFF. Disconnect the water supply from the water solenoid valve. Remove the front cover. Remove the two blue wires from the water solenoid valve. Rotate the self-tightening hose clamp so it can be loosened with a pair of pliers. Squeeze the clamp and move it down towards the shelf and off the valve outlet tube. Remove the two 1/4” - 20 hex head bolts and lock washers that attach the valve to the chassis. Pull the valve off the rubber fi ll hose. To install the valve, reverse these instructions. Test the unit per SECTION 7: OPERATIONAL TEST.
D. LEVEL PROBE REPLACEMENT:
Disconnect power from the unit. Remove the front cover. Note where the blue and black wires are connected to the triple pronged water level probe. Disconnect all three wires from the water level probe. Using a 1-1/4” box wrench, remove the level probe. Install a new level probe. Use Tefl on Tape on threads of probe if required. Tighten until the bottom of the plastic nut is 1/8” to 3/8” inch above the top of the port. See diagram 16. Reattach the three wires. Test the unit per SECTION 7: OPERATIONAL TEST.