HARVEY Chemiclave EC5500, Service Manual, Page: 33 / 56

33
M
AINTENANCE AND
S
ERVICING
Figure 18: Pressure Relief Valve Replacement
Pressure Gauge
The pressure gauge only indicates pressure. It has no
effect on temperature. Failure of the gauge is highly un-
usual. Before replacing the gauge, check other causes for
pressure changes.
Pressure Relief Valve
The pressure relief valve releases pressure at the rating
marked on the valve. After prolonged use, the pressure
relief valve may leak at lower pressures. If it leaks, first try
to reseat the valve. If unsuccessful, replace the valve.
Checking for leaks
UNIT AT ROOM TEMPERATURE
1. Pressurize the unit. To do this, perform steps 2-4
of “leaks at Fittings.”
2. Brush the opening ports with soapy water. Leaks
will appear as bubbles or foam that grow larger.
UNIT HEATED TO OPERATING TEMPERATURE
1. Turn control knob to PRESSURIZE. If liquid
collects around the ports of the pressure relief
valve, the relief valve is leaking.
2. Pull the ring to clear debris and reseat the valve.
Check again for leaks.
3. If the valve still leaks, replace it.
Pressure Relief Valve Replacement
1. Depressurize the unit.
2. Remove the cover.
3. Remove the pressure relief valve (see Figure
18).
4. Install the new pressure relief valve.