No.8 Thermostatic Fixed-Temperature Discharge Steam Trap Installation and Maintenance Instructions

1. Safety information
2. Product information
3. Installation
4. Commissioning
5. Operation
6. Maintenance
7. Spare parts

1. Safety information

The safe operation of this product can only be guaranteed if it is properly installed, commissioned, used and maintained by qualified personnel (see Section 1.11 of this document) in accordance with the operating instructions. General installation and safety instructions for pipeline and plant construction, as well as the proper use of tools and safety equipment, must also be followed.

1.1 Intended use

Refer to the installation and maintenance instructions, name-plate and technical information sheet to check that the product is suitable for the intended use/application. This product complies with the requirements of the European Pressure Equipment Directive 2014/68/EU.

This product falls within the following Pressure Equipment Directive category:

i) This product has been specifically designed for use with steam, air or water/condensate in Group 2 of the Pressure Equipment Directive referred to above. Use of the product with other fluids may be possible, but if this is being considered, contact Spirax Sarco to confirm the suitability of the product for the application under consideration.
ii) Check the suitability of the materials, pressure, temperature and their maximum and minimum values. If the maximum operating limit of the product is lower than the limit of the system in which it is installed, or if product failure could result in dangerous overpressure or overtemperature, ensure that the system includes a safety device to prevent such excessive conditions.
iii) Determine the correct installation location and the direction of fluid flow.
iv) Spirax Sarco products are not intended to withstand external stresses that may be induced by the system in which they are installed. It is the installer’s responsibility to consider these stresses and take adequate precautions to minimise them.
v) Remove protective covers from all connections before installation.

1.2 Accessibility

Ensure safe access and, where necessary, provide a safe working platform with suitable protection. Arrange suitable lifting equipment where required.

1.3 Lighting

Ensure adequate lighting, particularly where detailed or complex work is required.

1.4 Hazardous liquids or gases in the pipeline

Consider what is in the pipeline or what may previously have been in it. Consider: flammable materials, substances hazardous to health and extreme temperatures.

1.5 Hazardous environments around the product

Consider: explosion-risk areas, lack of oxygen, such as tanks or pits, hazardous gases, extreme temperatures, hot surfaces, fire hazards, such as during welding, excessive noise and moving machinery.

1.6 The system

Consider the effect of the proposed work on the entire system. Could any proposed action, such as closing isolation valves or electrical isolation, put any other part of the system or personnel at risk?

Hazards may include isolating vents or protective devices, or rendering controls or alarms ineffective. Ensure that isolation valves are opened and closed slowly to prevent system shocks.

1.7 Pressure systems

Ensure that any pressure is isolated and safely vented to atmospheric pressure before carrying out maintenance on the product. Consider double isolation, double block and bleed, and locking or labelling closed valves. Alternatively, a Spirax Sarco DV-type relief valve may be installed; see the separate literature for details. Do not assume that the system has been depressurised even when the pressure gauge indicates zero.

1.8 Temperature

Allow time for the temperature to return to normal after isolation to avoid the risk of burns.

1.9 Tools and consumables

Before starting work, ensure that suitable tools and/or consumables are available. Use genuine Spirax Sarco replacement parts only.

1.10 Protective clothing

Consider whether you and/or others in the vicinity require protective clothing to protect against, for example, chemicals, high or low temperatures, radiation, noise, falling objects and hazards to the eyes and face.

1.11 Permits to work

All work must be carried out by suitably qualified personnel or under their supervision. Installation and operating personnel should be trained in the correct use of the product according to the installation and maintenance instructions.

Where a formal “permit to work” system is in operation, it must be complied with. Where there is no such system, it is recommended that a responsible person is aware of the work being carried out and, where necessary, arranges for an assistant whose primary responsibility is safety.

Post “warning notices” where necessary.

1.12 Handling

Manual handling of large and/or heavy products may present a risk of injury. Lifting, pushing, pulling, carrying or supporting loads by bodily force can cause injury, particularly to the back. You are advised to assess the risks, taking into account the task, the individual, the load and the working environment, and use suitable handling methods according to the circumstances of the work being undertaken.

1.13 Residual hazards

During normal use, the external surface of the product may become very hot. If used at the maximum permissible operating conditions, the surface temperature of the product may exceed 250 °C (482 °F).

Many products are not self-draining. Take particular care when dismantling or removing the product from an installation; see the maintenance instructions.

1.14 Freezing

Provision must be made to protect products that are not self-draining from freezing when they are exposed to temperatures below freezing point.

1.15 Disposal

This product is recyclable. Provided suitable care is taken, its disposal will not create an ecological hazard.

1.16 Returning products

Customers and stockists are reminded that, under EC Health, Safety and Environmental Laws, when returning products to Spirax Sarco they must provide information regarding any hazards and the precautions to be taken due to contamination residues or mechanical damage that may present a health, safety or environmental risk. This information must be provided in writing, including health and safety data sheets relating to any substances identified as hazardous or potentially hazardous.

2. Product information

2.1 General description

The No.8 fixed-temperature discharge liquid expansion thermostatic steam trap is fitted with an oil-filled element and operates at a fixed temperature. It can be conveniently adjusted to discharge at any temperature between 60 °C and 100 °C (140 °F and 212 °F).

Note: For further information, refer to the technical information sheet TI-P018-01.

2.2 Sizes and pipe connections

1/2” threaded connections BSP T Rp (ISO 7-1) or NPT.

Figure 1 No.8 fixed-temperature discharge liquid expansion steam trap

2.3 Pressure/temperature limits

Pressure psi g

The product must not be used in this area.

The product should not be used in this area or beyond its operating range, otherwise the internal parts may be damaged.

3. Installation

Note: Before carrying out any installation, observe the “Safety information” in Section 1.

Refer to the installation and maintenance instructions, body markings and technical information sheet to check that the product is suitable for the intended installation:

3.1 Check the materials, pressure, temperature and their maximum values. If the maximum operating limit of the product is lower than the limit of the system in which it is installed, ensure that the system includes a safety device to prevent overpressure.
3.2 Determine the correct installation location and the direction of fluid flow.
3.3 Before installation in steam or other high-temperature applications, remove protective covers from all connections, where applicable.
3.4 The steam trap should be installed below the equipment to be drained, with the inlet below the equipment. The outlet should always be above the steam trap.
3.5 Due to its fixed-temperature discharge characteristics, the liquid expansion steam trap can be effectively used as a “shutdown drain trap”. Its outlet must always point upwards, as shown in Figure 2, so that the oil-filled element remains immersed. It must discharge through a drain line that is open-ended, terminates below its body and leads to a safe location. Since it can discharge only between 60 °C and 100 °C (140 °F and 212 °F), it must be installed together with a “conventional” main drain trap, which is normally connected to the condensate return line.
3.6 Isolation valves must be installed to allow safe maintenance and replacement of the steam trap.
3.7 Slowly open the isolation valves until normal operating conditions are reached.
3.8 Check for leaks and correct operation.

Figure 2

4. Commissioning

After installation or maintenance, ensure that the system is fully operational. Test any alarms or protective devices.

5. Operation

The Spirax Sarco No.8 fixed-temperature discharge liquid expansion steam trap is one of the simplest thermostatic steam traps currently available. Under cold conditions, such as during start-up, the oil-filled element is completely clear of the valve seat, allowing cold condensate, air and other non-condensable gases to discharge without obstruction. When hot condensate enters the steam trap, the oil-filled element expands as it heats up and presses the valve onto the seat, closing the valve. By turning the adjusting nut, see Section 6 “Maintenance”, the element setting can be adjusted so that the discharge temperature of the steam trap, that is, the temperature at which the valve reopens, varies between 60 °C and 100 °C (140 °F and 212 °F).

6. Maintenance

Note: Before carrying out any maintenance procedure, observe the “Safety information” in Section 1.

6.1 General information

Before carrying out any maintenance on the steam trap, the steam trap must be isolated from the supply and return lines, and any pressure must be safely reduced to atmospheric pressure. The steam trap should then be allowed to cool. When reassembling, ensure that all mating surfaces are clean.

6.2 Adjustment

Note: The No.8 thermostatic liquid expansion steam trap is factory calibrated, but initial adjustment may be required as follows:

• Loosen the adjustment locking nut (5) at the end of the steam trap.
• Turning the adjustment nut (1), which is connected to the element (8) at one end, changes the position of the valve head (9) relative to the valve seat (11), thereby changing the operating temperature.
• Turning the adjustment nut (1) counter-clockwise causes condensate to be discharged at a higher temperature, i.e. hotter.
• Turning the adjustment nut (1) clockwise causes condensate to be discharged at a lower temperature, i.e. cooler.
• Retighten the adjustment locking nut (5) to the recommended torque (see Table 1), ensuring that the adjustment nut (1) does not turn with it.
• Open the isolation valve slowly so that pressure and temperature rise in a controlled manner.
• Check for leaks.

Figure 3

6.3 How to replace the element set

Remove the steam trap from the pipeline, unscrew the adjustment locking nut (5), remove the adjustment nut (1), and take out the element (8).
Use a screwdriver through the inlet connection to unscrew the valve seat (11). Replace the valve seat (11) and gasket (10), and tighten to the recommended torque (see Table 1).

• Fit the new element (8), ensuring that the round-headed guide screw (6) is aligned with the slot.
• Fit the new overload spring (2), refit the adjustment nut (1) and adjustment locking nut (5), and tighten to the recommended torque (see Table 1).
• Reinstall the steam trap in the pipeline and reset it.
• Open the isolation valve slowly so that pressure and temperature rise in a controlled manner.
• Check for leaks.

Figure 4

Table 1 Recommended tightening torques

Item	Part		or mm		N m	(lbf ft)
5	Adjustment locking nut	11 15/32" A/F			80 - 85	(59 - 63)
11	Valve seat		1/2" UNF		30 - 35	(22 - 26)

7. Spare parts

Available spare parts are shown in solid lines. Parts shown in broken lines are not available as spare parts.

Available spare parts

Element set

2, 8, 10, 11

Figure 5

How to order spare parts

When ordering spare parts, always use the description in the “Available spare parts” column and state the size and model of the steam trap.

Example: 1 - Element set for a Spirax Sarco 1/2” No.8 thermostatic liquid expansion steam trap.