Does anyone have experience with Spacepak Hydronic HVAC?
RebeccaHCA
| Posted in Mechanicals on
Zone 6, north of Toronto, Canada
I am building a new house and I’d like to build a high efficiency home with low energy costs. I have come across Spacepak’s air-to-water heat pumps and their hydronic system and I wonder if anyone has experience with these? Does it work well and perform as expected?
I understand it’s a more expensive system. I’m also wondering if the upfront cost justifies the energy cost savings over time.
thank you
Rebecca
GBA Detail Library
A collection of one thousand construction details organized by climate and house part
Search and download construction details
Replies
The question isn't about reliability but about cost and complexity.
Once you have a place that needs cooling you are running ducts, so any hydronic option only adds costs and complication. A ducted heat pump is a fraction of the cost of an air to water heat pump and air handler. Never mind the cost of all the hydronic bits and labor. Also add on there the there are very few people out there that understand hydronics, and even fewer that can set up an air to water properly. Mix hydronic cooling in there, the installer base is even smaller.
Not saying it is not possible but you really have to be of the tinkering mindset with a deep budget get it installed and running well.
If you are set on air to water, my suggestion would be a simple air to water that does localized floor heat in areas you would notice. This means much smaller unit and the floors can be run hotter so you actually get the warm toes feel. It can also be a simple direct to load plumbing with no extra controls just what comes with the air to water unit.
For the rest of the space heat, cooling and ventilation, install a regular ducted cold climate heat pump.
P.S. If you price out the cost of the air to water floor heat above, VS the cost of resistance heat for the same area, good chance is ROI is many decades.
"If you are set on air to water, my suggestion would be a simple air to water that does localized floor heat in areas you would notice."
To add on to what Akos is saying, I feel the biggest mistake people make is sizing heated floors for design load, so they only reach full operating temperature during design conditions, which is the 99th percentile of temperature or roughly 88 hours per year. If you size that way, on a typical winter day they're barely on at all and you don't get the "warm toes" you're paying for. You want to size that localized area so that it's on almost the entire winter -- if you need heat at all, it's on. If it's not enough -- which it won't be below about 55F outside -- then use that heat pump cold climate heat pump to make up the difference.