Geoman (and others),
Consider this a blanket reply to some of the posts already.
1. Yes, standard for this zone (central pennsylvania) call R-25 a
minimum in the attic and R-49 the recommended value. While increasing
the amount of insulation does help, it also reaches a point of
diminishing returns. I've installed an additional R-25 over the
bedrooms where the thermostat is present and it has show no difference.
2. Actually, the contractor working on it is taking it at the pace I
originally requested. He first checked the charge and settings on the
system, fixed some horrendous duct work issues, did a basic system
check and moved the thermostat from the open hallway over the living
room (where it kicked off when the fireplace was on). I asked him to
check back after I had a week or so of cold weather to analyze whether
those fixes helped. He just hasn't had the chance to get back and
check out the air handler. When I called him last, he is the one that
asked me to check the inlet and exit air temperatures and indicated it
should be something closer to 20-25 degrees.
Geoman, comments below to yours. Thanks.
Geoman wrote:
Did they install the geo pipe into water wells? What antifreeze
solution did
they use?
The vertical wells are closed loop. They drilled through limestone,
but did hit water in some regions. I believe the solution in the pipes
is a methanol solution, don't know what concentration.
Do you mean the loop water line or an actual refrigerant line? If its
a
refrigerant line then you have a split unit? thats were the
compressor is
separate from the air handler? Is the air handler in the attic or
conditioned space?
Yes, it is a split unit. The refrigerant line runs crom the compressor
to the air handler. The air handler is in the attic - unconditioned
space. I also noticed they only used R-4 supply pipes in the attic,
but the temperature drop from the unit exit to the room supplies is
minimal.
Now, to the winter and the problems. The loop seems to be working
fine
- loop temperatures and pressures are reasonable. The 1st floor
unit
works like a dream. We have a set temp of 72 deg and even on the
recent days when it's been near zero, the unit does not run
full-time
and maintains temperature. The inlet air temp at a return on the
floor
is about 70-71 and the exit air temp at the supplies are about 95
degrees. All of this is great, except for the fact that it must be
working harder to help the second floor.
This is NOT an indication that everything is fine!!! All this tells
me is
the back up heat is working and your paying about four times the
amount of
electric than if your unit was running by itself.
My fault for not providing all the information. Up until last week
when it dipped below zero, I have had the breaker for the electric
backup on the first floor unit turned off. I haven't needed it. On a
standard 10 degree day the unit runs about 1/2 time to sustain the set
temp without the use of the backup. Only during the cold nights when
the 2nd floor temp has been dropping to 65 has the first floor unit
kicked the back-up on. I've been monitoring it and it has not been on
much.
My second floor air handler is running 24 hours a day and is still
failing to meet the set temperature.
Geo's will run all the time when its cold outside.
Again, just not what I'm seeing with the first floor unit. That's the
primary thing that confuses my new contractor. He said he would have
expected to see the first floor unit running full-time to try to
supplement the 2nd floor, but it's not working that way. It still
cycles on and off without calling the electric. The entire first floor
is comfortable.
I've checked and sealed any
ductwork leaks and added additional insulation to the attic. I've
got
R30 in the attic and R19 in all the walls. I don't think I'm
losing
R-44 to 48 is the standard.
heat to the attic because on a recent 18 degree morning it was
about 19
degrees up there. If I do a heat transfer balance based on the
R-values I should have and the 2nd floor temp, that was the correct
equilibrium temperature.
I'm also not losing it in the ductwork. The new contractor I have
looking at it put his gages on the lineset and said everything
looks
fine.
What else did he do? I need exact information here.
I'm not sure, I was not home at the time.
If I take the temperature at the inlet and exit of the air handler,
I
get a delta T of only 10 degrees.
All this tells me is the back up heat isn't working and the
geothermal unit
is. But it doesn't tell me what the geothermal system is actually
moving in
BTU's.
That is the one thing I am trying to rectify. The second floor air
handler was installed without the heater because the original
contractor (now out of business) indicated it wouldn't be needed. I
need to add the breaker and run the additional line up to the attic in
order to add the heater. That said, while some of this might be offset
by the heater, I still think there is an issue. Even on a moderate day
in the 30's, the unit runs non-stop and the exit air temperature is
low.
I'm pretty sure this is where the
problem is, but my HVAC guy has not been able to get out the last
couple days to diagnose it further.
Any thoughts? (and yes, I've changed the filter.)
Yep, I think your HVAC guy needs to be fired, there are tests that
will
prove what is wrong with your system. One thing I notice is the
upstairs
units back up reistance heat or what ever type you have isn't
installed,
hooked up or isn't working or being called to work.
The downstairs unit temperatures tell me that the resistance heat is
working
but maybe not the Geo. The HVAC guy could have done all the necessary
tests
without puting his gauges on the refrigerant lines. As a matter of
fact, if
this is the only thing he did you got ripped off big time.
Again, this is the third contractor - original one out of business,
second one just to charge the lineset for 2nd floor unit, and this one
recommended by other builders and the ClimateMaster distributor. He is
aware the 2nd floor unit does not have the electric backup and is
ordering one for me. However, his other houses in the area with Geo
are not having problems. My neighbor has the same ClimateMaster Split
system and has not even turned on the breaker for the electric backup.
They keep a slightly lower set temp, about 69.
I have a stick thermometer at home and will get the inlet and exit geo
loop temps tonight. If you have any other thought on simple things I
can check, I would appreciate it. What would help? Pressure reading
from the gage on the primary unit? Loop temps? Is there a way I can
get flow rate based on jumpers/dip switches and line diameters. I've
found the ClimateMaster manual to be mostly useless for troubleshooting
unless I get a fault code (which I'm not). The Trane air handler
manual has no technical specs whatsoever, so I'm not sure what kind of
delta T I should get across the air handler.
Thanks.
Jon
Thanks.
Jon
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