Idaho Trying a diy experiment

Discussion in 'General Discussions' started by David Knowlton, Mar 29, 2016.

  1. weedy64

    weedy64 New Member

    Just noticed "P" on the 14 pin terminal is pump call. 30Vdc and drops to 0V when water is required by HP. ie - compressor on.
  2. Haha nice catch. No, I don't think the ground will produce 55 degree water under load. I guess I'll see what it dose when I get the ground loop in. Not a big deal if it doesn't we still have natural gas. so if all that works is ac until I upgrade to a bigger unit I'm still happy.

    so what I need is a normally off 3-30v dc relay and it will work as designed? Thanks a billion weedy. :) I'll see what I can find on eBay, and the junk drawer. where do I terminate the P wire after the relay?
  3. I have thought about making a heat exchanger around my 80% efficiency furnace stove pipe and using the hp to recycle the heat lost through the flue pipe. as long as I can get the temp over 55degrees everything should work, ehh it will give me something to do when i get bored.
  4. weedy64

    weedy64 New Member

    I have a couple spare 24Vdc relays from one of my HPs, I can mail you one. Connect the coil of a 24vdc relay to P and either V (-dc) or F (+dc)com depending on the polarity you want for the relay control. The relay would also have NC or NO and common terminals to power your circ. pump. That is what you want this for, correct?

    Here are a couple PDFs with terminal information for what I think is your control board.!AgfSBRObCAzTgVpuFXfIXANp_guW

    IMO don't mess with your furnace exhaust pipe, it needs the heat to provide adequate draft in order to effectively exhaust the furnace, and you dont want the corrosive exhaust condensing and rotting out the pipe. A screw up with the integrity or flow in the exhaust can result in CO collecting in your house and dead occupants.:(
    Last edited: Aug 2, 2016
  5. Yes, I have a 3-36 vdc - 24-480vac n/o ssr but you said the voltage drops when the compressor is energized so I would need a nc relay so the circulation pump is energized when the voltage drops correct. Or can i swap that by using v or f? Sure, What do you want for them?
  6. About the flue pipe yeah i came to the same conclusion. It sounds cool though. :) turn a 80% into a he fernace. If it worked that well i could add a high temp blower and some pvc but thats not something i would want under my feet if something went wrong.
  7. Though if one was set or trying something like that putting a nest carbon/gas dector down in colose proximity if their was a leak the nest would shut down the fernace. Still bad idea, sorry im spending alot of time in the tractor during harves and the radio isnt keeping me entertained any more lol.
  8. weedy64

    weedy64 New Member

    I don't think you "need" my relays if you have that SSR, but you can have em for mailing cost if you want them. The heat pump P terminal is an active low terminal. If you connect the +terminal of your SSR to F(+dc) on the strip and the -terminal to the P on the strip, the SSR will turn on with the compressor, very elegant and silent. SSRs are much nicer than relays, I use them when ever I can. Just verify with a meter that the P and F voltages with respect to V (-dc) are not over 36V (the upper control voltage limit of your SSR).

    What r you harvesting and how many acres? I used to have a small sheep farm and grew up with a dairy herd and then beef/sheep. We grew hay and corn for such. If/when I get my bike back together I could be convinced to test drive Hwy 20 to an electrified hot-tub Idaho destination. I am a medical electronics technologist by day and was a farmer by night, I sold off my night job.
  9. Custom hay bailing moistly but we do have some grain up north on the home place. We have +/- 1000 down in brenueo and close to that between gooding and fairfield. Cool, i worked at st lukes last winter as an it tech. So are you like a cliencical endengneer?

    What kind of bike do you have?
    Last edited: Aug 4, 2016
  10. weedy64

    weedy64 New Member

    Radiation Therapy Electronics Technologist. Electronics, Mechanical, Plumber, Machinist, IT rolled into one.

    Kawi 1200 ninja - built for fuel efficiency;)
  11. Cool, i feel the same way to talented to be tied down to one profession. Lol if fuel efficiency was your goal why a 1200 lol. Hey maybe you could use one of those kits they use on kit cars that shuts down unused cilinders. Haha anyways I hocked up the relay like you said and wala. It even kicks on the pump about a second b4 the compressor kicks on. :) this should keep my filter a little cleaner. :) i may need a bigger pump though.

    The return to the hottub comes out way hot. I think i could gain a few more btus if i pump a bit faster.
  12. weedy64

    weedy64 New Member

    The tub pump runs all the time right? Could you not take a 1/2" water feed from the pressure side of the hot tub pump thru the HP and return via the suction side or filter plumbing of the hottub? Then you dont need a second pump at all just a flow control for the feed line. (about 2.5 gpm for 1T or set for delta T across HP)

    I realize the heated water will mix and some water gets double heated but we are talking about a 1/2" line feed line relative to an 1-1/2 hottub mainline. This all works good in HP cooling mode but what are you gonna do when its heating season?
  13. the pumps do not go all the time no, and I do have the take off on the 1.25 main and returned to the jets, but even with both circulating pumps on with way less restriction to the jets than the 3/4 inch lines to the heat pump only a trickle flows through the loop to the hp. the filter I have is a filter before the loop pump, which is a grounfos hot water circulating pump. Afeter the 90-106 water passes through the hp it come out about 140 F++ so I'm thinking of using a higher pressure pump to increase flow over the heat exchanger. (much like wind chill) I have a 12v rv pump that kicks off at 80 psi, I'm thinking if I get a valve for the relay and just leave the pump hocked up to a battery bank with a little charger should do the trick. Just a little trial and error getting the charger the right size for the real hot days and not cooking the battery on colder days. I do have an extra 240v hot tub pump and I'm tempted to use it for the hp loop but I'm afraid it would be too much resistance and cook the motor. 2" though a .5 inch fitting lol. :) like the ideas though thx :)

    the cooler I can get the heat exchanger the cooler the air blows into the house thus the more efficient the hp will be, and the less undersized it will be.
  14. weedy64

    weedy64 New Member

    which grundfos? did you crack the front plug to burp the air from it while running?
  15. weedy64

    weedy64 New Member

    my mistake

    the few hotubs ive seen had a two stage pump so that the water circulates 100% of the time. slowly to save $$ but some so the heater can cycle on and off and then into high speed to get the back beating jet power.

    a pic might help, why do you have a filter on loop? a mesh screen to take care of big chunks is all thats needed, maybe the circ pump doesnt have the head to overcome the filter or worse if its on the suction line. Pumps like to push not pull so a suction line filter is to be avoided. I read much about this on a recent online search, but it wasnt at home so ive got no links on this ipad, and its a turtle.
  16. The filter is just a screen sorry. And yeah ill load some pics. Its an older tub and one pump comes on for the heater when called and another for jets. But the heater is never used yet. But i warn you it looks a little getto. We plan on moving the tub and the hp so some stuff is just slaped together real redneck style lol. :)
  17. weedy64

    weedy64 New Member

    Nice and clean, unlike Rio's 2 pools
  18. The screens always dirty though. I ought to keep the pump clean until its in a closed loop.
  19. Ive taken out the screen and used 3/4 pe pipe from a pvc manifold to the hot tub shortening the pipe distance by about 60feet and installed the pump down in the basment. And my flow has more than doubled. Its coming through two jets now fast enoutgh to pull bubbles. :) that 26-99 has some spunk now. Two 1 ton units can heat the tub about a degree every 8 minuts. Were starting last cutting of hey tuesday so we probably wout get the loops in until after that. But ill keep you guys posted.

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