AquaStar 170 VP manual Procedure For Replacing A Thermostat, To Remove Thermostat

PROCEDURE FOR REPLACING A THERMOSTAT

TO REMOVE THERMOSTAT:

A. Your replacement thermostat comes as part of a kit. The kit includes additional replacement components to ensure a successful installation. When removing the old thermostat be certain to remove all its components ("O" Ring, and Steel Wedge) prior to installing the replacement thermostat.

1.Shut off gas to the heater by turning the handle on the main gas valve.

2.Shut off the water supply to the heater and open a faucet on the lowest floor to drain the line and relieve the pressure.

3.Remove the front panel, the left panel, and the bottom tray.

4.Remove the L-Shaped Lever, spring and screw (see fig.A). Screw is covered with a grey cap on newer models. Back out the screw all the way, being careful not to lose the spring, and then remove the L-lever. (Set these three parts aside as a unit, ready to reinstall).

5.Pull down on the thermostat piston assembly to remove it from the gas valve.

NOTE: There is a Steel Wedge and an "O" Ring which should come out with the piston assembly. If they do not, reach up with tweezers and/or a magnet for the Steel Wedge and remove them. Be especially careful not to push the Steel Wedge into the valve housing.

6.Remove the two screws at the other end of the thermostat (located on the upper left side of the heat exchanger) and slide the capillary sensor out of the heat exchanger. Note: You should have a basin ready to collect the water that will then be released from the heat exchanger.

TO INSTALL NEW

THERMOSTAT:

B. When working with the thermostat, be careful not to damage it: The copper capillary tube is hollow and can be damaged if crimped or bent too sharply.

1. Insert the capillary sensor into the

heat exchanger. Be sure that the

rubber gasket seats properly and

then retighten the two screws.

2. Slide the new Brass Collar over

the piston.

3. Slide the "O" Ring over the piston

so that it seats above the Brass

Collar.

4. Place the Steel Wedge into the

piston cup. Position it so it is ori-

ented with a flat side facing you. A

dab of grease or silicone will help it

stay in place.

5. Slide the assembly into the valve

housing, ensuring that the Steel

Wedge does not shift to an angled

position.

6. Reinstall the L-Shaped Lever,

spring and screw. Be sure the left

side of the L-lever is positioned over

the cam. Tighten the screw in all

the way so the spring is compressed.

Now calibrate the thermostat.

7. To calibrate the thermostat prop-

erly, continue with the calibration and

thermostat test on the following

Retaining screw

fig.A Capillary Sensor

Thermostat

Tubing toRubber Gasket

Heat Exchanger

			Steel Wedge
Cam			"O" Ring
		Spring	Brass Collar
		Screw
L-Shaped Lever		Grey cap	Piston Cup
	Thermostat		Thermostat assembly
	Piston
	Assembly

page.

Into Left Side of

Heat Exchanger

Complete Gas Block Assembly

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