Question:
I'm still thinking about heating water with 1/3 the usual energy using a Haier
5K Btu/h window AC ($84 at Wal-Mart.) The pipes connect to the condenser coil
at the top, so we could build a thin aquarium around it with no replumbing or
recharging and pump 1.5 gpm of 110 F water out through a $168 Doucette SB1-20
400 Btu/h-F plate heat exchanger with a 110 F thermostat and pump 60 F cold
water into the other side of the heat exchanger from a cold kitchen tap and
back into the hot tap, and dump some hot water from the hot tap into the sink
with a solenoid valve if the cold tap ever reaches say, 100 F, when/if the
tank water heater completely fills. Heating 50 gallons of 60 F water to 110
takes about 21K Btu, and the AC would make about 5000(1+1/3) = 6700 Btu/h,
so we might fill the tank in 3 hours, with no hot water use.
When I blocked the Haier AC condenser airflow to make the exit temp 110 F,
its cool air temp and power use (from a Kill-a-Watt) barely changed.
This could be more efficient than a typical "portable air conditioner" with
air hoses. Removing the condenser fan blade might also raise the COP.
Answer:
I like your thinking, it should work. I take it your not really thinking
about hooking hoses up to the spouts of the kitchen sink taps, but to
the pipes feeding them.
About 40 years a go one of my friends had a water cooled central air
system in his Massachusetts home. All the equipment was in the basement
furnace room. The cooling water went down the drain most of the time,
but he did have a valving setup which allowed him to water his lawn with
that warm water if he wanted to.
Googling "heat pump water heater" got over 49,000 hits, and it looks
like it's proven technology:
http://tinyurl.com/zpkpd
and:
http://www.aceee.org/consumerguide/topwater.htm
He didn't mention how he was going to handle switching the water
heater's original heating source back ON when he didn't need A/C. Or if
it's just a storage tank, what he was going to do with the cold air from
the A/C when he didn't need to cool the room.
Removing the condenser fan blade would provide a minuscule reduction in
motor power consumption, but if left there blowing air against the side
of that "aquarium" it'll just make some of the heat he's trying to put
into the water "fly away". Some thermal insulation around the "aquarium"
would seem to make sense though. OTOH if the design of the A/C had that
fan also blowing some air over the compressor to keep its operating
temperature down, then removing it might not be too smart
