Heat recovery unit?

[crashbox]

Hi all,

Hrlp! Just wondering about heat recovery unit economic viability...

What do they cost, how long do they take to pay back? Can they plumb into more than one existing compressor?

We have a single compressor for chilled water for plate cooler, and two compressors for the 10k DX tank. All old kit... Hot water used for 2xdaily circulation, calf feeding, EOD tank wash. Day and night rate leccy with time clocks on everything.

Cheers,

CB

 

[upnortheast]

Looked at heat recovery a few times but could not get the numbers to stack up. With the last grant round on standard costs it made sense standard cost was £7k. Fridge lad charged just over £4k so net £1300. Have 3 compressor s connected. Water is 55 to 60 degrees.
We have 6 compressors. Put a meter on each one for a week to see how much they each ran. That gave us a guide as to which ones were worth connecting to the system.. Looking like £500 year leccy saving so under 3 year payback

 

[upnortheast]

Was not an off the shelf system Each compressor had a little heat exchanger connected. Fridge gas one side. Water other side with a pump moving the water when the compressor is running. All connected to a cylinder.

 

[crashbox]

@upnortheast Great thanks for info, v. Helpful to see photos.

Looks just the kind of set up would suit us.

 

[Tullyvernon]

Was not an off the shelf system Each compressor had a little heat exchanger connected. Fridge gas one side. Water other side with a pump moving the water when the compressor is running. All connected to a cylinder.

How noticeable is the temp difference on each side of the refrigeration pipes?

 

[upnortheast]

Will check when I have a minute

 

[upnortheast]

Scientific answer ................ To touch ............ incomer very hot, outgoer warm.

Will get a thermometer on it if I get a chance tomorrow

 

[Tullyvernon]

Scientific answer ................ To touch ............ incomer very hot, outgoer warm.

Will get a thermometer on it if I get a chance tomorrow

Looks a good job, definitely a great option with multiple condensing units

 

[upnortheast]

Scientific answer ................ To touch ............ incomer very hot, outgoer warm.

Will get a thermometer on it if I get a chance tomorrow

The answer is,
Compressors all seem to run at slightly different temperatures
Temp of the water in the cylinder has an effect
but
Looks like the heat exchangers are dropping the fridge gas temp by circa 40 degrees C.

 

[crashbox]

The answer is,
Compressors all seem to run at slightly different temperatures
Temp of the water in the cylinder has an effect
but
Looks like the heat exchangers are dropping the fridge gas temp by circa 40 degrees C.

That's got to make a solid saving on compressor energy use/wear and tear, as well as the reduced heating bill. Sounds a great job!