Need help on low voltage heatpump wiring
robteed
| Posted in Energy, Heating & Insulation on
We installed a new Geothermo heatpump in our house. I have it working but it needed a Electric heat strip added because of frost buildup on the unit. I guess the heat strip is suppose to take some of the heating load off the HP to give it time to defrost the pex tubing lines.
The guy that sold us the heat pump isnt much help, it was sold as a DIY
kit. The pump has these connections :C:S:L:G:O:Y:R
The Electric heat strip has these connections :W1:G:W2:C:G1:R:W3 The wiring diagram shows W1:W2 are jumpered together, they can be disconnected.
The Thermostat is
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Geothermo heatpump in our house. I have it working but it needed a Electric heat strip added because of frost buildup on the unit
Some oxymorons in that phrase - you may have bigger troubles than you think. Frost buildup is common and expected on air-air units, but not on well installed ground source heat pumps (BTW, it is NOT geothermal unless ground temp is over 100F, the marketing people have corrupted the technical language, it is correctely called a ground source heat pump -- GSHP).
1st, the electric strip should never be needed on GSHP unless it is sub zeroF. (Hookup W1 as a minimum, different brands have different hookups, such as Rheem having the HP valve energized for heating, most everybody else energized for cooling, air-air defrost cycles differetc, etc.), so something further is (grossly?) amiss. Need more info for diagnosis, incl. details of setup, loops, trench size and depth or well configurations, TXV size/paralleling (probable from description?), etc.
For laughs, try posting your query over at HVAC-talk.com. Those guys over there really like to trash DIY HVAC. If you like abuse, that is <G> (typical response ---- bet you bought it on e-bay, serves your right, you took food out of my kid's mouths, etc. etc<G?>)
You need to trace thru all the schematics of the thermostat and your air handler and go from there, no simple answer that covers all cases.
To figure out why you have frost in the fist place that would require a strip heater, go checkout a good thermodynamics text or an AC manual from your library and get educated. The ARI "air conditioning and refrigeration manual" would be a good place to start.
Ok, but the wiring should be simple enough to hook up. I just need to know which wires need to be hooked up. What is the common way to do this. Im sure the wiring leters/numbers are an industry standard.
Do I just run a wire from the R and E from the thermostat? to the duct heater,
G Y R O to the heat pump.
I worried that if I wire this wrong the electric duct heater will be running at
the wrong times, creating a larger electric bill.
Will this wiring work correctly.
ya gotta have the "C" terminals connected, that is the 24 Vac return, usually the blue wire is used for that