Issue:
RTHD and Spring isolators
Resolution:
1. The use of spring isolators is generally not recommended for Trane screw chillers. A neoprene pad is shipped with every Pueblo RTHD, it is enough material to put under the entire surface of the chiller base.
2. The chiller base holes are meant for shipping purposes only, to secure the chiller to a wooden skid or pallet. The chiller base is not designed to support the weight of the chiller by a single point, as occurs when you mount the base on the spring isolator. The chiller feet are spot welded, with no continuous line weld or reinforcing structure between feet and legs. The chiller base is meant to be supported across all of its length by the neoprene pad or on a rigid surface, such as a beam.
3. Supporting the chiller by installing the isolators in the existing shipping holes in the base is not recommended. This kind of installation puts stress at the joints of the refrigerant piping and between the evaporator and condenser. Think of stress as generated by the cantilever effect. Do not add more spring isolators in the other shipping holes in the base. If the chiller base was a solid structure that would be fine (such as RTAC), but since the chiller feet are connected by the chiller piping and the bolts that hold the evaporator and condenser, it is not a good option. If four additional spring isolators are installed, the evaporator and condenser would become two different vibrating bodies, worsening the vibration of the chiller. Since this arrangement has not been tested or designed for, it is strongly discouraged.
4. If the spring isolators are still to be used, ideally they should be mounted underneath a beam that is supporting the overall weight of the chiller across the whole chiller base like on an I-beam or similar rigid support, not just point loads.
For a picture of a problematic spring isolator installation see the attachment. Remember this is an example of what NOT to do. INCORRECT Spring Isolator Installation.
Notes:
Changes:
Other Question/Problem/Cause Statements:
- RTHD and Spring isolators
- Can I use spring isolators?
- How do I install spring isolators?
- Where should I install springs isolators?
- How should we mount these chillers on spring isolators?
Facts:
- Water-Cooled Chiller (Pueblo) (RTHD)
Document Identifier: DOC-82054
WARNING:
Information in this article is intended for use by individuals possessing adequate backgrounds of electrical and mechanical experience and who comply with all federal, state, and local laws, rules, orders, or regulations related to the installation, service, or repair of a heating or central air conditioning product. Any attempt to install, service, or repair a heating or central air conditioning product may result in personal injury and/or property damage. The manufacturer or seller cannot be responsible for the interpretation of the information contained herein, nor can it assume any liability in connection with its use.