Can I ask a tech question on a heating-A/C unit here?

[rod...@rodneydickman.com]

LG:  LA120HSV2

My plan was never to use this LG mini split wall unit for heat but in looking for a way to A/C the sun room I am building I found they are also heat pumps so I want to use the heat feature. I have a 24 volt DC controlled hot water heated floor (in the concrete poured floor) in my sun room (uses a heat exchanger and my house water heater - simple and neat). The heated floor is in now.

  LG offers an add on circuit board (PQDSBC) (I can email a copy of the booklet if need be) for this LG unit - is there anyway to control an external relay so when the LG unit is making heat the LG unit provides a DC current to close a relay? Or a way to get a signal off that board to somehow power another circuit board (which I can make if need be) to then close a relay? Or a way to get a signal off the LG unit (LA120HSV2) so when it is providing heat I can control the floor heat with a relay or? This would require 2 thermostats and that would be OK with me. The heated floor would be set at maybe 65 degrees on a 24 volt Honeywell mercury type thermostat. The LG unit would be set lower than 65 degrees on its digital LG direct wired wall thermostat so it does not run on cold days. The in floor heating would keep the room at 65 degrees but it is very slow to bring the room warmer. To heat up the room quickly just raise the LG thermostat and every time the LG provides heat the pump for the heated floor would also run keeping the floor warm. You would have 2 heat sources running simultaneously when you raise the temp over 65 degrees. You would run wires in parallel to the Honeywell thermostat. When you turn the LG unit down the in floor system maintains the room at 65 degrees and the LG unit does not run.If I can not do this every time I raise the LG unit for heat the in floor heat would shut off as it would be set at 65 degrees. Had a known this earlier I would have put a PVC tube in the floor so I could put a probe in the cement in the heated floor. I have not yet tiled the floor so I could still install a probe under the tile.

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[rod...@rodneydickman.com]

On Tuesday, October 2, 2012 6:55:42 AM UTC-5, rod...@rodneydickman.com wrote:

PS: Looking at the minutes of a previous meeting someone mentioned that the majority of the posts here are from only a small handful of regulars. I'm guessing you may have discussed this but have you considered starting a on line forum?

[Kevin Crowley]

https://groups.google.com/forum/?hl=en&fromgroups#!forum/milwaukeemakerspace

On Tue, Oct 2, 2012 at 6:59 AM, rod...@rodneydickman.com <rod...@rodneydickman.com> wrote:

On Tuesday, October 2, 2012 6:55:42 AM UTC-5, rod...@rodneydickman.com wrote:

PS: Looking at the minutes of a previous meeting someone mentioned that the majority of the posts here are from only a small handful of regulars. I'm guessing you may have discussed this but have you considered starting a on line forum?

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[Mrspeed]

Yes,

Rich

Sent from my MOTOROLA ATRIX™ HD on AT&T

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[Brant]

Floor temp sensors are pretty common and that would be the easiest way to do it.  You could also install a timer relay so that if the LG unit doesn't get the room up to temperature within say... 30 minutes, the floor kicks on.  Adjusting the temperatures to get a desired result is a bit tricky and your best bet is to determine what temp you want the room at, and then decide how to control the equipment to achieve that.  It should be possible to wire in a relay to do this.

On Tuesday, October 2, 2012 6:55:42 AM UTC-5, rod...@rodneydickman.com wrote:

[rod...@rodneydickman.com]

 I've been pondering this and I think I'll do the floor sensing type thermostat with a probe. We did not put in a tube to insert a probe into the cement floor but the tubing for the system is around 2 inches below the top of the cement slab. So I will grind out a valley maybe 3/8" to 1/2" deep part way into the room and set a tube so a probe can be inserted (and removed if it needs replacing). I've found it a bit hard to find a simple wall mount non programmable 24 volt thermostat. Just a simple on of and degrees setting is all I want. Many have multiple settings, set back times etc. But I found a couple.

Thanks
Rodney

[Mrspeed700]

I may still have some mobile home ones let me look.
Rich

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[ironmonger]

Menards had them last year. About $20. Just a simple heat and cool and cool stat.

Paul
WB9HCO
No trees were killed sending this message, but a tremendous number of electrons were terribly inconvienced...

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[rod...@rodneydickman.com]

The thermostat I want will need to have a hard wired probe to insert into the floor. I want to control the temp of the cement floor with the probe thermostat. I can't use a standard wall thermostat. It would fight with the wall thermostat for the heat pump-A/C unit.

Thanks
Rodney

[Mrspeed]

I have several t stats 12-30 volt

Rich

Sent from my MOTOROLA ATRIX™ HD on AT&T

ironmonger <pspe...@gmail.com> wrote:

Menards had them last year. About $20. Just a simple heat and cool and cool stat.

Paul
WB9HCO

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[Mrspeed700]

I am trying to assemble all the parts for a duo therm climate control system. It will have several temp sensors , 5 separate heat and cool zones, This should meet your needs?
Rich

-----Original Message-----
From: Mrspeed <mrspe...@aol.com>
To: milwaukeemakerspace <milwaukee...@googlegroups.com>

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