We have a geothermal system in an ICF (to the top of the 1st floor) house with an HRV. We have separate venting for the kitchen cooktop, a direct vent gas fireplace, and makeup air for the woodstove. All bathrooms are on the HRV system. I'm a little fuzzy on the insulation, since DH kept changing his mind. In the dormers and gables of the 2nd floor, we have baffles with I think a combination of 1" of whatever that expensive polywhatever is in the attic, along with blown-in cellulose, and 1" of XPS on the outside. Everything was built and inspected according to our state's code which incorporates the IRC 2003 code, which has since been updated. DH researched this a LOT, and asked lots of questions of HVAC installers, suppliers, and manufacturers. There were times when he had to explain some of it to the inspector. He thinks he got it all right, although I remember him getting conflicting views on whether we should use an HRV or ERV, since apparently we're sort of on the border climate-wise as to which one is most suitable. Anne

Everything else outside sounds like it's running... the unit doesn't shut off. When it's blowing the warm air and the fan stops, the unit makes a loud buzzing sound and you can feel it putting off hot heat. As soon as the fan starts back up the sound goes away and it pushes out cold air. I haven't taken anything apart on the outdoor unit yet. But I took the panel off the indoor unit and it looks like new on the inside. I'll look at the outdoor unit more in depth tomorrow. Are those two things something that I can replace and if so, how can I tell which part may be bad?

Do you have flexible or rigid ductwork? How long has this been going on—is this a recent decrease in comfort/airflow or has it always been like this? Do you have the same problem when the system is in heating mode? Take some pictures of anything you can see (without jeopardizing your safety/comfort, of course!), please. It could be something simple, like a kink or an incomplete connection.

I'm disappointed that what had at first seemed a very balanced comment was followed by what seems to be misinformation and misdirection. People buy ground source heat pump equipment because they want to and can afford it. Or decide they need to in their locations. They're hugely more expensive than alternatives, which is why they're still not very common. "When’s the payback on a Tesla? People still choose to buy them for reasons other than the ‘bottom line’." Not a comparable. A false analogy. "I would not choose natural gas or propane for reasons relating to the environment, safety, IAQ & paying for yet another utility hookup for an energy source that might not even be used for months on end during the year." What effect having a gas furnace has on indoor air quality. Another hookup? Most people prefer gas cooking appliances and besides, the OP is talking about an existing home, he either has gas service or he doesn't. "Rather than spending perhaps tens of thousands of dollars on a Solar Array, I would sooner invest that same money, hopefully less, in a ground loop for a Geothermal system." Sure you would, that's the business you're in. The ground source heat pump market is not growing as expected by those in the industry, which suggests that your opinion isn't widely held or easily sellable. In many parts of the country, solar panels can have a quick payback. Not so ground source heat pumps. "I often hear about Solar Panels when geothermal is mentioned, as an alternative way to save money by creating energy." In a place like Texas, where electricity is cheap (other than during cold weather crises as they just experienced) there's likely no payback from a solar panel installation. People do it as a personal statement, call it for environmental or other personal reasons. Like buying the Tesla, not a financial decision. An HVAC system blows warm air when it's cold, cool air when it's hot. It's one of those things people don't care about - either it works or it doesn't work. Spending extra money for an exotic system doesn't equate to extra payback when the home is sold. Neither owners, nor visitors, nor people passing by, nor anyone else, concern themselves with what's doing the work. It's equipment that doesn't produce an experience for someone in the house if it's working. In the US, there are vast areas where electricity is cheap. It will remain so for some time. People don't spend money today to potentially save money 10 years out when market conditions may or may be different. I suspect you could build a house with mahogany or teak framing. Or you could paint the framing bright colors. Why bother, you can spend less money and effort and get something else that will do the same job. "We almost never use setbacks at our home - even when going on vacation for weeks on end with no one home, our geothermal just runs." You're combining two different things to produce confusion. Thermostats that have a setback feature ALL are set up to provide lower overnight temperatures to have more comfortable sleeping conditions and then a recovery in the morning before wakeup time. As sleep specialists recommend. That in demand comfort features isn't possible with ground source heat pumps because the warm up period from a setback is too slow to be convenient to use, absent triggering a secondary heating source (like a furnace) to help. THAT'S why you don't "believe" in setbacks with a heat pump - they don't work. Turning down a thermostat during heating season when the home will be unoccupied is not a "setback" as that word is most commonly used. It's done to save money, why heat a vacant house? No setback thermostat is needed, even a dumb 50 year old analog thermostat can be turned down.