Check hydronic system water pressure

Why It Matters

Water loop pressure drifts down slowly through the year. Low pressure reduces heating performance and can trigger a system lockout.

How to Do It

1. Locate the pressure gauge on the hydronic heat pump unit or buffer tank.
2. Read the label near the gauge to find the acceptable cold-system pressure range, typically 12-15 psi.
3. Compare the current gauge reading to that range.
4. If the pressure is low, locate the fill valve (usually a small valve on the supply line near the unit) and open it slowly to add water until the gauge reaches the low end of the labeled range.
5. Close the fill valve and recheck the gauge after a few minutes to confirm the pressure holds.
6. If the system loses pressure again before the next annual check, call a professional to find and repair the source of the leak.

Related Tasks

• Bleed radiators or in-floor loops Once a year
• Clean hydronic heat pump outdoor unit Once a year
• Clear snow and ice from hydronic heat pump outdoor unit Once a year
• Schedule hydronic heat pump tune-up Once a year