Has anyone tried adding heat to their heat pump with warm water or air to make it more efficient?

[Partimewages]

45 does not seem worth the effort but possibly worth a try to satisfy the curiosity.

Pump the water through a radiator mounted next to the heat pump with a moderate enclosure so the air drawn in pulls through the radiator first.

I guess I'm not seeing the point of this. Ground source heat pumps use the water through the refrigeration process to extract or reject heat.
There are all kinds of problems with trying to cool/heat an air source coil with water. You likely won't make it through 2 seasons.

 

[Hedges]

45F water vs. freezing or super-chilled air should be a huge improvement in keeping house at 68F. 50% or greater reduction in temperature delta that heat pump has to work across.

 

[Jbird2000]

here it is about 10k usd per hundred feet. thats for a 10" bore for a water well. I can rent a bulldozer or backhoe and move the earth out of the way to a 6' -8' depth, lay out all the pipe in a grid pattern spike it down and then use the bulldozer to cover the pipe up to the expected 6' depth. so for me that or a combo backhoe with dozer blade would be cheapest, and would be 2-3 days for a skilled operator, or about a week for me.

We do not have window units here in japan, (inverter or otherwise.) and the US ones would not fit the japanese sized windows anyway. the normal high quality 1.5~2 ton split packs range from a low of 1000USD up to about 3000 USD for one with a lot of bells and whistles. you can buy that same 3k USD splitpack for about 1k when it is used and one year old. personally i would opt for a larger one without all the crazy options that will eventually go bad. the cheaper units run as low as 2-300 USD used when they are 1-2 years old. easy pickings to experiment with.

I did NOT use a water well drilling company. I used a mining drilling company. I did not care if I hit water if I was going to use a closed loop with methanol/water mix. The 2 x 300' wells cost me less than 1/3 of what a water drilling company charges. incoming water mid winter is about 43F. They just pounded away fast until the target depth hit They hit 15 gal a min so I ended up going with a pump and dump of the raw water out of 1 well and into another. I heat and cool my 4000 sf home with about 8000kwh of electricity. I am on a net meter program so I easily cover winter usage with my bank with the power corp. I do have a desuperheater on my geo system with a buffer tank on my HW. The geo itself uses approx 3500 watts (in the winter) and the submersible pump about 1600watts

I would love to add some solar to that system and power the lower elements from those solar panels. Not sure if there are people doing that. I am not allowed to add more solar to my net meter program system. Will have to dig thru the forum to see

 

[Hedges]

1600W to perform zero net work, lift water 300' then pour it down to the same depth.
How much pressure loss from the flow rate?
Any chance you could install micro hydro down the second well shaft and recover some of the lost power?

 

[Partimewages]

1600W to perform zero net work, lift water 300' then pour it down to the same depth.
How much pressure loss from the flow rate?
Any chance you could install micro hydro down the second well shaft and recover some of the lost power?

This is pump and dump. House well and use a solenoid valve. Takes more pumping watts but higher capacity and efficiency.

 

[Jbird2000]

1600W to perform zero net work, lift water 300' then pour it down to the same depth.
How much pressure loss from the flow rate?
Any chance you could install micro hydro down the second well shaft and recover some of the lost power?

Hmmmmmmmmm food for thot

 

[Partimewages]

You must be the dealer I thought of? Pump 'n dump (Open Loop for the uninitiated) here. Up well and dump to riverbottom, back property line 1/2 mile away IS the river. Use the same well as house supply, never been a problem. While the inexhaustible water supply increases geo efficiency, I assumed it's net lower with pumping wattage (?)

Edit: Would you look at the Geocool / Mr Cool modular and offer opinions on it?? They are around $6k.

https://mrcool.com/wp-content/dox_repo/mc-gci-br-eng-01.pdf

I don't see anything wrong with this other than it doesn't seem to have a desuperheater. As long as you can source parts for future repairs it's probably okay. My assumption is the 6k is complete unit.

 

[Plum Crazy Rob]

I don't see anything wrong with this other than it doesn't seem to have a desuperheater. As long as you can source parts for future repairs it's probably okay. My assumption is the 6k is complete unit.

Hmm yeah you're right, desuperheater where is it ?
Yeah who knows until someone gets one or YouTube or something so we can get a good look parts quality etc.

Thanks. Seems like a weird market for Mr Cool to move into??

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[Daddy Tanuki]

I did NOT use a water well drilling company. I used a mining drilling company. I did not care if I hit water if I was going to use a closed loop with methanol/water mix. The 2 x 300' wells cost me less than 1/3 of what a water drilling company charges. incoming water mid winter is about 43F. They just pounded away fast until the target depth hit They hit 15 gal a min so I ended up going with a pump and dump of the raw water out of 1 well and into another. I heat and cool my 4000 sf home with about 8000kwh of electricity. I am on a net meter program so I easily cover winter usage with my bank with the power corp. I do have a desuperheater on my geo system with a buffer tank on my HW. The geo itself uses approx 3500 watts (in the winter) and the submersible pump about 1600watts

I would love to add some solar to that system and power the lower elements from those solar panels. Not sure if there are people doing that. I am not allowed to add more solar to my net meter program system. Will have to dig thru the forum to see

wish I had that as an option, here in Japan you play by there rules and there are no companies that drill holes that deep other than companies that drill wells. they are the same compnaies that drill for deep construction pylons, and test holes to test the soil for (whatever) in construction. so you pay XXX yen per meter regardless of if you hit water or do not hit water.

here on fuji it costs over 100,000 USD to hit water due to the nature of the soil (volcanic rock and gravel) the elevation (hence depth required to hit water table etc). so most wells are drilled by groups of people that put their money together to get one drilled and they all share the costs etc.

if I was on one of the lakes I would run the black plastic out into the lake and tie it to the bottom, no such luck there as I am over 5 miles away, so if I do do it will have to be a trenched type with the coils laid out in a grid.

 

[Partimewages]

Professional Opinion
Any DIY equipment of any sort has to be priced to sell. The company selling has to make a profit or they don't survive. If that equipment sells for what wholesaler sell then some corners are cut. Most of those cuts look right now to be coming from China.
Is the equipment good? Only time tells. When a professional company install and support the equipment there's where the value is added. Wholesalers sell to the contractor and only support one dealer for multiple pieces. DIY doesn't have that. Just be careful!

 

[OzSolar]

I've pondered putting a series of HP water heaters in a greenhouse and locking them out so they only run when the green house is above a certain temp. Perhaps 80f or more? (not saying it's a good idea just that I find it an interesting mental exercise)

That heated water would be used for radiant floor heating and if things were sized just right you might be able to get your efficient house through at least one night following a sunny day. A Rube Guldberg of a solar water heater!

One tricky bit is that they would cool the greenhouse which would lead to reducing thier efficiency.

I've looked around a little bit and can't find any charts that detail a HP water heater's energy usage/efficiency vs. ambient temp but it seems reasonable to assume that they'd make more BTU's for less kWh's the warmer the space they were in.

 

[RCinFLA]

If you just spray warmer water on outside unit's coil it will likely turn into an ice machine. Unit's defrost cycles will not be able to keep up with the ice buildup rate.

Many folks in FL listen to TV weather reporters that tell them to turn on their sprinklers to help protect their plants during a nighttime freeze.

 

[Daddy Tanuki]

If you just spray warmer water on outside unit's coil it will likely turn into an ice machine. Unit's defrost cycles will not be able to keep up with the ice buildup rate.

Many folks in FL listen to TV weather reporters that tell them to turn on their sprinklers to help protect their plants during a nighttime freeze.

View attachment 185471

was this winter or summer in florida?

 

[toadman03]

I don't think consuming fuel such as in the rocket stove to heat input of heat pump delivers any extra energy. Just use heat from that directly.

If you have earth temperature water to feed the heat pump, that should do well. one meant for ground source would have been the way to go. If you can run a refrigerant line through the water that ought to work. Not touching the heat pump system, maybe just pump water through a radiator on air intake side of heat pump.

So my property has concrete walkways all around it and no access for a drilling rig so I had to go air source. It didn't occur to me until after it was done and running and through our first winter that I have a lot of water I am pumping out from under my basement that isn't freezing when it gets outside. Currently I have a 6 watt pond pump making a little fountain outside 4 hrs on and 4 hrs off all day and night and that usually keeps my sump from running and it isn't freezing either. So I'm trying to figure hlout how to pass the heat from the water to the heat pump without having to dismantle / vacuum out the refrigerant etc. I could run the water over the coils but then they could freeze of they bring the temp down too much. Could love to be able to submerge a set of the condenser could in a container with this water cycling through but I don't think that is possible. I have a Fujitsu halcyon unit. It has space for 2 more heads but I know it only works one direction to the heads so I can't take a head loop and try heating that since its on the wrong side of the compressor

 

[Hedges]

I have 15' of refrigerant line between evaporator and condenser, also a large pool. I've thought of either bonding a water tube outside the line (after air-cooled condenser, not optimum), or splitting and sealing a tube around the outside. I suppose it could just be a trough sealed at the ends, high enough to drain back to pool.

One of the HVAC guys here said using a "desuperheater" carries risk of making compressor ingest liquid. Caveat Hacker.

 

[Partimewages]

How much water do you have? I need a GPM. Without that it would just be an expensive experiment.

 

[Partimewages]

I have 15' of refrigerant line between evaporator and condenser, also a large pool. I've thought of either bonding a water tube outside the line (after air-cooled condenser, not optimum), or splitting and sealing a tube around the outside. I suppose it could just be a trough sealed at the ends, high enough to drain back to pool.

One of the HVAC guys here said using a "desuperheater" carries risk of making compressor ingest liquid. Caveat Hacker.

Yes, you can't just throw another heat transfer system into an already designed system or you take the chance of destroying the refrigerant system.

 

[Hedges]

Although I don't understand how cooling refrigerant to about earth temperature is any different from operating the system after it was off, under normal temperature conditions. Perhaps could regulate outlet temperature by speed of pumping water, and turning off fan in condenser.

I have a pool, so can recirculate any flow rate. I don't have a heat pump at this time, so it would be to improve efficiency of A/C. Especially on hot days, when compressor works harder.

 

[Daddy Tanuki]

Yes, you can't just throw another heat transfer system into an already designed system or you take the chance of destroying the refrigerant system.

pretty sure if you lower or raise the temp of the condenser it would be no different than running it in that time of the year temp wise.
so if ambient is 75 °f (late spring/early summer for me) and your water temp you have the condenser in is 55°f that it (compressor and control circuit ) would look at it the same as if it was in 55° ambient. or the same as winter end/early spring for me. it would be more efficient, but I cannot see that causing an issue. (you might need less gas, but if you have a set of gauges you can adjust for that. i work on small scale refrigerated equipment and small scale under counter reefers, so maybe not the same level of experience as you might have but not a total idiot either

 

[justgary]

I have a three ton pump and dump system with desuperheater. The ground water comes in at about 75°F. The system needs around eight gallons per minute when cooling to keep the high side pressure from getting too high.

I would jump at the chance to trade the scroll compressor in it with an inverter compressor.