Best Of
Re: Trying To Estimate Heat Pump kWh Usage
@Jamie Hall : "The COP of a heat pump varies with source air (or water) temperature. Therefore any calculation of power usage by the heat pump must take into account that variation. The relationship of COP to source temperature varies for different types of heat pump, so you need to be looking at specific makes and models for the calculations to make any sense at all."
If you look at the spreadsheet he linked to, that's exactly what he's doing. There's a row for each degree with estimates for heating load at that temperature, annual hours at that temperature, and heat pump COP at that temperature.
The COP is going to depend upon both temperature and percent of capacity, variable speed heat pumps have higher COP at lower utilization, at least until they start short-cycling. So it also depends upon how the system is sized to the house.
Re: Trying To Estimate Heat Pump kWh Usage
It's epidemic in the industry that installers don't trust the Manual J process and put their thumb on the scale to drive the result they want. With combustion appliances it wasn't a big deal, oversizing doesn't really impact efficiency and undersizing is a big problem. With a heat pump you want to size accurately.
Are your ceilings really only R19?
Re: Help with Goodman GSXC16 Error code 04
As was explained to me, apparently the larger the capacitor the more current it can pass but the less phase shift you get. A hard start just adds another capacitor to give the start winding more current. Apparently it needs to be pulled out because you end up with less phase shift so the motor runs worse. I guess it's a balancing act to get enough current with the right, or as close as you can to the right amount of phase shift.
It's not going to pull any more current starting than it wants just because you add capacitance regardless of it's name. It should probably be called an easy start, but I guess it's name comes from being used on motors that have a hard time starting.
This info was given to me by an engineer with a PhD in electrical engineering about 8 years ago, so I might remember slightly off.
ChrisJ
Re: OT: Underground Wiring Options
" So I'll assume that even though a low voltage and/or ethernet cable PLUS a pex could fit in the 3/4" pvc, it probably wouldn't be legal. But another 3/4" PVC line now would be a very wise choice. "
Even if you intend to put 1/2" PEX through 3/4" PVC you may be severely disappointed. 1/2" PEX has an outer diameter of about 5/8". Between the bend radius and any excessive glue that oozed into the conduit you may never get it through.
With electrical conduit work they only allow 40% (3 or more conductors), 53% (1 conductor) fill of the conduits available cross-sectional area.
As @mattmia2 stated you need to think much bigger. And use electrical conduit type radius not water pipe type radius.
109A_5
Re: Discolored hot water / HTP PH 76-60 hot water heater installed 5 months ago
how did you test the chloride level, what is that number? What is the HTP limit?
Chlorine level tested with color strips?
hot_rod
Re: OT: Underground Wiring Options
I'd probably do like 2". You can use 4" black plastic drain tile too, can pull things that don't have much of a code requirement in that like direct bury low energy wiring and maybe water. There seem to be few rules about buried water piping. If you do conduit, bury it and put some plumbing caps on the ends, digging up the ends and connecting is much easier than digging another trench.
mattmia2