constant problems with new installation of Climate master digitial 30

1) Where you live - Washinton DC area
2) Heat loss/gain calculations for your home - not sure
3) Brand, size (model) and type of heat pump - Claimate Master TEV049 Digital 30 4 ton
4) Type of loop field (open/closed/vertical/horizontal) size and design parameters - horizontal closed loop around 600 ft
5) Average cost/Kwh of electricity and consumption - not sure
6) Entering and leaving air temperatures (EAT, LAT) measured immediately upstream and downstream of the heat pump - leaving air temp 75.5
7) Entering and leaving water temperatures (EWT, LWT) measured at the heat pump(s) EWT: 29.9 LWT:44.8
8) Percent of load to be covered by geo and balance point: installer yet to give
9) Installers assessment of your systems operation. - installer not clear
10) Projected operating costs, actual operating cost and previous heating and cooling costs - installer yet to give

Hi,
We have 2500 sq. ft 1959 built brick house 2 storey (new roof and new attic insulation to ~R35). My installer took about 4 months to install new geo system from July - oct 2012. Once it is installed we had constant problems with heat pump stopping with thermostat reporting error code E4 (low water temp). In Jan/Feb 2013 installer replaced the circuit on the heat pump. That also did not solve the issue. Also we have 85 gal. buffer tank hooked up to collect hot water from de superheater that feeds into the main gas water heater.

Installer is blaming the heat pump.

Desperately looking for some advice.

Thanks,

 

Is the machine in cooling or did you get your water temperatures backwards?

Mark

 

One of the things we look for in the temps you provide, is Delta T's (D/T) or temperature differentials. The Delta T on your water side if accurate suggest that you may not be circulating water quickly enough (installer needs to raise GPM/reduce D/T). That could easily spiral down to low water temp in times of high demand.
-However-
Your air side D/T would be interesting to know but you provided only leaving temp. The leaving temp is awfully low suggesting either low house temperature (55ish)- or unit not extracting much heat (which is contrary to a 15 degree water D/T)- or poor measuring device
-and if it is a poor measuring device (laser for instance), GIGO. I take back what I said about changing GPM.
......make sure data is accurate, provide EAT as well, then I think we might have more useful ideas.

 

The machine is in HEAT mode. Sorry when I gave the readings it was in aux. heat mode, that is the reason LWT was high. because the water flow rate is very low.
Also I have seen the D/T settings with the installer. initially heating D/T was 5 deg and cooling was 10 deg. Last week installer changed the D/T for heat to 8 deg.
That seemed to do some help. But no matter what we set the inside temp. to, in 30 mins. time thermostat complains low water temp. (E4 error code) and switches to aux. heat.

just took another reading from thermostat (thermostat is set to heat 70deg. with inside temp 69 deg.) and outside temp 38 deg.:
LT1 temp 28.0
LT2 temp 96.0
comp. discharge 168.4
hot water ewt 66.0
leaving air 96.4
leaving water 26.8
entering water 32.7
ecm blower rpm 865
ecm target cfm 1400
pump watts 39
flow rate gpm 4.1
pump speed 58%

 

A 4 ton system with 600' of horizontal pipe? Is that 600'/ton or total?

Bergy

 

It is the entire loop for 4 ton.

 

Also since last night the outside temp. was more than 45 deg. and the system has been running without any hiccups at 69 deg. thermostat settings. I took another reading. Today evening around 7pm EST when the temperature was aroumd 51 deg. outside I increased the thermostat setting from 69 deg to 74 deg. Below are the thermostat readings before the system locked out:
LT1 temp -5.4
LT2 temp 88.2
comp. discharge 168.7
hot water ewt 93.9
leaving air 85.6
leaving water 44.2
entering water 31.4
ecm blower rpm 859
ecm target cfm 1400
pump watts 31
flow rate gpm 1.3
pump speed 60%

My installer is telling me there could be some communication error on the thermostat itself and offering me to change it with a regular honeywell make. If he does that I cannot read these data anymore coming from the climatemaster igate thermostat.

 

600' feet of pipe is woefully short for a four ton heat pump as is a flow rate of 1.3 gpm..

 

"The machine is in HEAT mode. Sorry when I gave the readings it was in aux. heat mode, that is the reason LWT was high. because the water flow rate is very low."
Oops I missed that the EWT was the lower number. That said you should not have a 15 degree delta in aux.
The new numbers are incomplete as I said before we look for D/Ts but can't determine them if you only give one temp. (leaving air 96.4.......).
Your water side D/T looks about right now.
was your loop system perhaps 600' of trench with 6 pipes in it?
Your newest numbers show a backward water side D/T again (doesn't make sense in heating) it also shows 60% pump speed with only 1+gpm which doesn't make sense without an obstruction. Makes me wonder about ice. What is the level of antifreeze in your brine.
I would also get an electronic tire pressure gauge to verify low flow on the pressure ports provided.

 

I'm not sure how to measure entering air temp. I will get a thermometer and try to place it on the return duct and check. Driller used trenchless horizontal driller and looking at loop diagram he provided about two weeks ago there are 3 drills. around 100' long each. He told one time the antifreeze he put can protect it to 20 deg.
He took around 3 months to drill and install the loop.

 

Can you please tell me a ballpark (very rough) figure for the loop size?

 

I have a 4.5 ton heatpump with 6000' of pipe.in a slinky loop. I would think you should have 1200' at least maybe twice that much in horizontal drill.

 

If the data you are reporting is accurate, you have way to much load for the amount of pipe you have in the ground. You are also only circulating enough fluid to support 1 ton of load.

Rules of thumb are very bad when delivered via the internet, but here goes. The minimum amount of pipe per ton of load is 300'. The flow rate should be 3 gpm per ton of load, so you need on the order of 12 gpm to handle your 4 ton load, and 1200' of pipe in the ground to handle 4 tons.

I think I speak for everyone here when I say " I hope the data you have provided is inaccurate ".
Eric

 

Does your installer have a track record of successful installations that would indicate competence where loop sizing is concerned? If not I'm with the others, you may need more loop. I think we are seeing a loss of GPM due to icing.

 

The TE30 needs to be programmed via a communicating thermostat or a service tool. I would bet yours is programmed incorrectly. Your EWT doesn't seem to match the loop lengths you provided. You can send me a PM if you want help with the programming.

 

Below is the response I got from my installer, so looks like I have around 825ft-900ft total loop.
"
As for design, we have made it clear that your house was designed per code, which is 68 degrees @ 17 degrees outside. We can only do an approximate analysis, as it is a retrofit application, changing a "size for size" with the existing system, within the range of output considering oversizing due to geothermal. In our region for heating, we design the difference to be supplemented by Auxiliary heat in almost all conditions, although in your case, we did upsize the geothermal for heating and design cooling for the single stage size for size.

Your house has been specified for a 4 ton heating geothermal system, with single stage supplying about 3 tons in cooling mode with your oversized loop. Your existing system was a 2.5 ton, or capable of producing somewhere in that figure. The remaining heat is supplemented by an additional 10kW heat strip, producing an additional 33,400 apprx BTU load. This should in all means satisfy your heating requirements.

You have 3 separate 1" loops grouted to .78 conductivity for your loop system. These three loops are each around 275'-300' each. This will satisfy your ground exchange.
"

Also he is telling the communicating thermostat is buggy and due to that heat pump is going off, so in a day or two he will be replacing it with a regular honeywell thermostat and program the pump to run @ a fixed speed using the service tool.

 

900 ft of horizontal bore pipe usually do not support 4 tons of heat. Are the 3 loops connected in series or in parallel?

Please do us all a favor and measure the temperature via the ports in the pipes going out into the loopfield and coming back, usually via a needle thermometer. You reading it off the thermostat might not be accurate. You also need a pressure gage to measure the pressure differential between incoming (EWT) and outgoing loop pipe (LWT), which will tell you the flowrate.

 

You know it's so much easier to help when you don't have to ask questions twice. What is your installers track record?
I have had a bad thermistor cause the same problem on a TZ22. It is easy to do an ohm test on it.

 

Sorry, I'm not sure about the track record of the installer. Few weeks ago he changed the main circuit board of the heat pump (which did not fix the main issue of heatpump going off).

Can you please give me a link to amazon.com or other site where I can buy thermometer and pressure gauge and any other accessories I need?

 

Cooper Atkins DFP450W-0-8 or similar reduced tip diameter thermometer works well for temperatures.

A sports ball needle inflator plumbed to a reasonably accurate pressure guage works well for pressures.