Bypass desuper heater with Sporlan ORI

[AndyHX]

Hey guys , ive built a w/w heatpump for under floor heating . The desuperheater i have has shown to be to small and is restricting the high side , i do get alot of domestic hot water from it but it pulls COP and under floor capacity down.
I thought i could put in a Sporlan ORI to bypass around the condenser and to maintain a certain amount of pressure in desuperheater.

http://www.coolingequipment.co.nz/sites/default/files/product_documents/Sporlan%5CHead%20pressure%20control%20valves/Head%20pressure%20control%20valve%20bulletin.pdf

Any one see any problems with this?

Cheers Andy

[Brian_UK]

The desuperheater is before the condenser, yes?

So putting in an ORI/ORD bypass to bypass/backup the condenser shouldn't really affect the desuperheater flow.

[AndyHX]

hi Brian , i see i made a typo above and have changed it.
yes desuperheater is before condenser. My plan is using only the ORI not in its usual position , it will tee in before the desuperheater and join back in before condenser. i will not use ORD. This way i can direct just enough through desuperheater and majority to condenser.

The issue i am having is desuperheater has large pressure drop and is almost doubling the kws used at 50hz that it should be using , according to coolpack and also select7.

Thanks
Andy

[Brian_UK]

If you reduce the flow through the desuperheater are you going to get sufficient duty from it to make it worthwhile using it?

Sorry, this isn't my area of expertise but I do enjoy reading Sporlan stuff - so - have you looked at using a 3 way heat reclaim valve?

Have s look here .. http://sporlanonline.com/literature-and-educational-materials/solenoid-valves/
and read document 30-217

[AndyHX]

yeah those Sporlan bulletins are a good read Brian ,
i guess the benefit of the ORI i s adjustablility , go for max desuperheat in summer cooling and back it off for winter heating.
The 3 way heat reclaim is probably a bit supermarket sized solution and price.

[Brian_UK]

^^ Yep, fair comment.

[AndyHX]

Im going to give it a go , i cant see any downsides.
I dont have a discharge service valve before the desuperheater but im quessing with the kws used condenser pressure was up to mid 60s . ill post results.
Cheers
Andy

[AndyHX]

Ok so got this running as good as it can , i cut in the ORi between desuperheater and condenser and i can now adjust how much flow is going through dsh , this has allowed me to increase the range i can run compressor up to.
It was using 3kw at 40Hz , now at 55Hz it uses 2.2kw . Condensing pressure is now down from mid 60c when 100% through dsh to early 30c at full bypass.
COP is between 6.4 at minimum to 4.9 at maximum , not including pumping .
So pretty happy with changes.
15236

[AndyHX]

Sorry for photo on side , if any knows how to change it ill do it.
Thanks
Andy

[Brian_UK]

Thanks for the update Andy, looks promising.

[blacktigra]

Hi AndyHX

Could you be so kind to show more pictures of your heat pump?
I'm curious about function of ORI valve.
Thank you.