How the system works
Each space has its own heat pump, connected to a shared water loop. A unit in cooling rejects heat into the loop. A unit in heating takes heat out of it. A cooling tower or fluid cooler removes excess heat, and a boiler adds heat when needed, keeping the loop within its design temperature range.
The advantage is that every tenant controls their own space and heat can be moved from one side of the building to the other. The disadvantage is that there are many compressors, spread through occupied areas, all depending on the same water.
Where they fail
- Water flow. Closed or failed valves, plugged strainers and scaled heat exchangers cause high and low pressure lockouts. It is the most common root cause we find.
- Hoses and fittings. Rubber hose kits age and leak. Above a finished ceiling, a small leak becomes an expensive one.
- Condensate. Blocked drains and rusted pans overflow into the space below.
- Compressors. Usually the result of years of poor flow or dirty filters, not bad luck.
- Reversing valves. A unit that works in one mode and not the other.
What good maintenance looks like
- Filters changed on schedule in every unit, including the ones that are hard to reach.
- Condensate drains and pans cleaned and treated.
- Hose kits and isolation valves inspected, and replaced before they fail.
- Operating temperatures and pressures recorded so decline shows up as a trend.
- Loop water treatment kept in order. Poor water chemistry damages every unit at once.
Planning replacement
Units installed together tend to fail together. A condition survey that records each unit's location, model, age and performance lets you replace by floor or by riser on a schedule, at a negotiated price, instead of one emergency at a time.
For vertical stack units, a replacement chassis can often slide into the existing cabinet, reusing the risers and avoiding work inside the wall. For ceiling units, a like-for-like replacement keeps the water, duct and electrical connections where they are.
When to call us
If you are seeing repeated lockouts, leaks, or a growing list of units that do not keep up, we can start with a survey and give you a clear picture of the building, unit by unit.