Keeping a ground-source system in good shape

What can a homeowner do?

Most of the owner's job is the air side. Check the filter every month or two in the heating season, and replace it when it looks grey. A blocked filter cuts airflow, raises compressor strain and lowers efficiency. Keep supply registers and returns clear of furniture. If the system has a hydronic side, glance at the pressure gauge and look for drips around fittings.

Write down the readings you can see: loop pressure, supply and return temperatures if the unit displays them, and the date. Over a few winters the notes make a trend, and a trend makes problems easy to spot.

What happens during an annual service?

A technician typically checks electrical connections and the controls, inspects the blower, tests the condensate drain, measures the temperature difference across the unit, and looks at refrigerant circuit readings. On the ground side they check loop pressure, flow, antifreeze concentration where used, and the condition of the circulation pump. They may flush or test a coil if scaling or fouling is suspected.

Refrigerant work is a job for a licensed professional, not a homeowner. Ask what the visit covers before booking, and keep each report. Records support warranty claims and show a buyer later that the system was looked after.

What about the buried loop?

In a sealed, well-installed loop there is nothing to service in the pipe itself. The thing to watch is the system pressure. A slow, steady drop may point to a leak or trapped air, and a sudden drop is worth a call straight away. Fluid freeze protection should be checked occasionally, since a diluted mix can raise the risk of freezing in a cold spell. Keep the as-built drawing of the loop with your house papers so future digging avoids it; this ties to the long-life points in ground source heat pump lifespan.

Common warning signs

• Weaker heat or longer run times than usual.
• Water around the indoor unit, often a blocked condensate line.
• Unusual noises from the blower, pump or compressor.
• Loop pressure dropping or alarms on the controller.
• Higher electricity bills in similar weather.

If you suspect loop trouble, compare the readings against the commissioning figures. The sizing assumptions behind those figures are discussed in borehole depth and spacing.

A lesson from a large installation

The Drake Landing community ran a much larger buried-pipe system, with a monitored Energy Centre controlling pumps and valves. Even with that attention, maintenance problems built up in its later years and contributed to its wind-down. The scale is different, but the lesson carries to a house: small, regular checks cost less than late repairs. For general equipment care across other heat pump types, see the heat pump maintenance checklist.

A simple yearly calendar

Keeping to a calendar helps more than good intentions. In early autumn, replace the filter, clear the vents and book the annual service before the heating rush. Through winter, check the filter monthly and glance at the pressure gauge. In spring, look for any water around the unit and confirm that the condensate drain flows. In summer, if the system provides cooling, listen for unusual noise and keep the area around the unit clear.

The same fall routine overlaps with general preparation covered in the winter home energy checklist, so the two tasks can be done on the same weekend. Keep a short log: date, filter size, readings and the name of the technician. It costs a few minutes and makes later problems much easier to diagnose.

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