Cooling space with vented heat pump exhaust
dpasowicz
| Posted in General Questions on
Hey all,
We are in the planning phases of an upcoming basement remodel and one of items in our design is a small dedicated wine cellar. The traditional insulation and climate control methods are straight forward enough, but I am wondering if there is a possibility to also upgrade our water heater to a heat pump and vent the cold air to either fully cool the cellar or at least decrease the thermal load. In my searching, I haven’t been able to find any good examples of anyone who has used vented heat pump exhaust to cool a separate area. Does anyone know of any previous examples they could point me to? Thanks
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Replies
They are normally vented into conditioned space, which is why you can't find examples -- it's so normal it's not noteworthy.
Possible but with some caveats..
- the cold air will make a hit on the COP of the heat pump
- what happens when the storage is cold enough but the water still luke-warm? Use the HP just as a pre-heater is not that economic. You could introduce some make-up air whenever that condition exist. I am not sure about moisture control - if you are happy with close to 100% relative humidity??
Thanks so much for the replies. I think I was unclear on the potential setup. The warm are the water heater heat pump would use would be from the general basement, while the cooler exhaust air would be vented to the wine cellar. The wine cellar would be a room within the basement itself so it would result in a positive pressure in the wine cellar so I would plan for the vent into the room and the door to be at opposite ends since some portion of the will eventually seep back into the house. The humidity is what gave me the idea since a wine cellar is typically also 60-75 percent relative humidity.
ah - ok. So you take the air from the basement and run it into/through the wine cellar.
With the air volume (flow) of these units you will exchange the wine cellar air several times an hour.
Better check the spec of the heat pump you are looking at, spec. what delta in air temperature is normal from inlet to outlet - then you can estimate what will happen.
Gut feeling from me - it will be too warm for wine storage unless you run a bit of the waste air back from the wine cellar to the inlet of the heat pump as the means to control wine cellar temp. Some motorized damper controlled by that temp.
I think the problem you're going to run into is that there's no easy way to thermostatically control the wine cellar. I'd look at a packaged through-wall heat pump for the wine cellar, with the heat dumped into the basement. That could cool and heat as needed. Then have the heat pump water heater pull air from the basement too, whatever heat is shed by the wine cellar is available to it.