Heat pump water heater in a Chicago townhome
As the title suggests, we live in Chicago and have a 4-story townhome. Our top floor is a small bedroom that has a louvered-door utility closet with a gas furnace and gas water heater.
The gas water heater is showing its age and probably needs to be replaced soon. I’d like to put a heat pump water heater in instead of replacing with another gas heater. I had one company come out to give a quote and the estimator basically told me a heat pump water heater doesn’t make sense in Chicago, full stop.
Everything I’ve read about heat pump water heaters says you should put them in a room with excess heat. Our top floor definitely fits that description due to stack effect, especially in the summer. That location actually seems like an ideal place for a heat pump water heater IMO.
I would love to hear your opinions on whether I’m thinking about this the right way.
Oh and one more thing: If a heat pump water heater does makes sense, should we vent it to the outside? I’m thinking not since we’d likely have to change damper configurations with the seasons (which I very well may forget to do) and I’d like to avoid as many wall penetrations as possible.
Looking forward to hearing your thoughts!
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There's zero reason why a heat pump water heater wouldn't work in Chicago. The "concern" would be the incoming water temps are "too cold" but they're not - they'll always be above freezing obviously, which is something heat pump water heaters nationwide can sometimes see. Chicago weather is not special.
There are absolutely limitations - a HPWH can't recover as fast as some other tanks can, but it will 100% work.
From an energy standpoint, a heat pump water heater makes sense everywhere, especially if you’re talking about a 240v version. I think about it like this:
Your heat pump water heater is stealing heat from your house, so in the cold season it is essentially heating itself with whatever your house is heating itself with. In hot season it’s heating itself with outdoor heat(which has heated your house) and thereby cooling your house.
So even if you only ran it in heat pump mode during non heat season, you would save a lot of energy, then you could just use its resistance element in heating season.
But if you heat your house with heat pump, it will also be more efficient to run than any other water heater during this time as well, because others use either gas or resistance.
And this all assuming you don’t have an over heated room in your house during heating season that is just losing heat anyways.
and dont vent to outside, there is a tiny window when this is more efficient but in general it is not.
In term of dollars and cents they may not make sense depending on your local fuel costs.
If you goal is to cut off your gas service and get rid of 100% of the gas appliances then a HPWH is the best option.
Note they now make HPWH that run on 120 volts so you may not need to run a new circuit to power the HPWH.
Does the utility closet have a drain for the condensate from the HPWH?
Will you be able to live with the noise the HPWH will make so close to a bedroom?
I think it would be foolish to vent the HPWH to the outdoors. The cool air expelled by the HPWH will be about 15° cooler than the air in the house. If it is 70° inside you would be expelling 65° air outdoors. 100% of that air get replaced with outdoor air that might be -20°. You would be throwing away 85° of heat that would be wasteful.
I also think it is foolish to replace working equipment simply because is seems old. The old water might surprise you and chugging along for many years. I do like the idea of having a replacement plan for the day is starts leaking. Remember Reduce Reuse only then recycle. So keeping the current equipment in service is the greenest thing you can do.
Walta
HPWH will work fine but I think it will be too noisy to put in a bedroom closet. Even if you can tolerate it, it's very likely the next homeowner wouldn't and replace it, cancelling out any "green" effect of your HPWH operation.
I purchased a State HPDHW for my new apartment above my new barn. We are currently living in that apartment. I located the water heater inside the conditioned garage and vented the exhaust into the car space to funnel cool, dry air toward my collector cars.
The air in the garage is kept around 55-60 degrees with other heat pumps. The HPDHW is working wonderfully and costs me about 12 Kwh per week. Seriously. There's an app that accompanies the water heater and tracks the Kwh. In CT, that's about $4 bucks per week!
The only drawback I see to your proposal is having a water heater high up in your structure because of potential leaks. Other than that, it should work great.