Well, if I do some napkin math, based on what I know about the unit, here's what I get:

Running in 1st stage, the compressor consumes 3 kw. Running continuously, that is 3 kwh x 24 hours = 72 kwh per day.

72 kwh/day x 30 days = 2160 kwh per month

2160 x.16 per kwh = $345.60

So does that seem reasonable for a system running 24/7 for a month, not including any other power requirement or aux heat?

You said you previously had oil. Is your HWH electric now?

Posted By stickman on 04 Mar 2015 08:28 PM
You said you previously had oil. Is your HWH electric now?

It is still electric. Was electric before. The new tank was installed with the geo and is still electric

Looks pretty good for consumption, roughly $12/day, in bad winter weather, $360/month, due to relatively high electricity costs.

Again, your problem might be solved.....Don't let them touch the TXV valve ... yet.

I am on Long Island, NY and have a 4 ton unit. My electric rate was 17.7 cents for the period from 1/20 - 2/20. It cost me approx $320 for heat and HW. Tstat was usually set to 70-72 all day long, and this was a very cold stretch, so I used some aux too.

Posted By docjenser on 04 Mar 2015 09:06 PM
Looks pretty good for consumption, roughly $12/day, in bad winter weather, $360/month, due to relatively high electricity costs.

Again, your problem might be solved.....Don't let them touch the TXV valve ... yet.

Thanks, Doc. So my usage/costs seem to be what might be expected? Is there anything else left to troubleshooting the TXV? If I'm not getting lockouts any more, should I just forget the TXV replacement until/if another fault shows up?

I've added a Climatemaster communicating thermostat to my system. Picked one up cheap on Ebay and I now have it wired directly into the DXM2 board. I plan on mounting it to the side of the unit and just using it to monitor the system data. It was cheaper than buying a service tool. I wish there was a way to log all that data.

"So does that seem reasonable for a system running 24/7 for a month, not including any other power requirement or aux heat?"

No. Why would you only use first stage continuously all month? That is not a real scenario.

Posted By joe.ami on 06 Mar 2015 09:48 AM
"So does that seem reasonable for a system running 24/7 for a month, not including any other power requirement or aux heat?"

No. Why would you only use first stage continuously all month? That is not a real scenario.

Like i said...napkin math. I know that it has run in stage 2 and with AUX heat quite a bit. That's why my electric bill is $900 last month and not $345

First you must seperate the regular consumption which you suggested was $250-$300. We'll assume it would be $300 with the fan running on the old heat pump making your heating electric about $600.
Ditching the "napkin math" which does not use real factors, let's go real math.

$600 in heating electric= high
Without over active auxiliary subtract $200-$250 = remaining bill not bad for heating your house in an unusually cold month.

Yes, forget the TXV replacement for now. Your problem appears to be solely caused by low methanol levels in the loop.

Posted By docjenser on 07 Mar 2015 07:43 PM


Yes, forget the TXV replacement for now. Your problem appears to be solely caused by low methanol levels in the loop.

Well, as it turns out, we had another LT1 lockout last night around 11:30PM. Really odd considering the weather is getting warmer. We didn't even realize it until after the lockout had cleared itself and the system was running again, about 2 hours ago. Here's the lockout data:

LT1 Temp: 9.9
LT2 Temp: 75.6
Hot Water EWT: 116.2
Comp Discharge: 190.9
Leaving Air: 87.4
Leaving Water: 26.2
Entering Water: 31.8
Flow Rate GPM: 9.5
Pump Speed: 90%


Any thoughts now? Is the TXV the next likely culprit or something else?

Aaaaaaannnd...Another lockout again last night, 12:39 AM. So that makes two lockouts, on two different nights, what were definitely the warmest nights we have had in quite a while.

LT1 Temp: 9.9
LT2 Temp: 75.5
Hot Water EWT: 110.6
Comp Discharge: 187.2
Leaving Air: 87.8
Leaving Water: 26.2
Entering Water: 31.2
Flow Rate GPM: n/a
Pump Speed: 90%

And as I type this and look remotely at the system data, the system appears locked out again and in aux heat. I reset it this morning (it was locked out) before I left for the office, it ran for probably 25-30 minutes and then shut down. Now I see my loop temps rising and the aux heat is on. Damn, this is frustrating.

Well, I got home and reset the system to clear the lockout. It ran for about an hour and locked out again. That's three times today alone. I'll be putting a call into the installer in the morning but can anyone give me any ideas here? From the data I see, things don't look much different than they did before except now the lockouts are really frequent. I did check pressure on the loop and it's at 25PSI when not running. Delta P was 6PSI but pressure never got higher than 32. I thought I read that loop pressure should be around 50+. Not sure if that has anything to do with it.

Low loop pressure will not cause your unit to lock out. The system will work fine any where between 15# and 50#.

Posted By Palace Geothermal on 10 Mar 2015 08:53 PM
Low loop pressure will not cause your unit to lock out. The system will work fine any where between 15# and 50#.

Good to know, thanks.

Could try a brief cycle in cooling again.

Posted By joe.ami on 11 Mar 2015 09:00 AM
Could try a brief cycle in cooling again.

Thanks. I will look to try that again later today. In the mean time, I have turned off the DSH and no lockouts yet. It has been about 4+ hours. The system has not run more than an hour continuously since the lockouts returned. We shall see what happens. Waiting on the installer to call me back. They have the replacement valve and are looking to schedule that.

ET, really? Back to the DSH? Understand in troubleshooting multiple changes muddy the water. So if it stops locking out after you reverse it to cooling is it the cooling or turning off the DSH that fixed it?
Or is it the warmer weather?

Posted By joe.ami on 12 Mar 2015 07:19 AM
ET, really? Back to the DSH? Understand in troubleshooting multiple changes muddy the water. So if it stops locking out after you reverse it to cooling is it the cooling or turning off the DSH that fixed it?
Or is it the warmer weather?

I get what you are saying. Really, I do. But as much as everyone keeps telling me the DSH has absolutely nothing to do with anything related to LT1 lockouts, all I can say is that when I am experiencing lockouts and I turn off the DSH, the lockouts stop. I can't explain it, but there it is. That is my experience. In the mean time, the system that would not run for more than 1 hour without locking out has now been running for over 24 hours without a lockout. Perhaps I will go home later today and turn the DSH back on to see what happens. If you have any suggestions for troubleshooting, I'd be happy to try something else. I don't have refrigeration gauges, so I can't test that part of the system, but I can try a lot of other things.

ET,
The Desuperheater will not cause a LT1 lock-out. Something in the system must be very marginal so when you "steal" a little heat from the compressor discharge line it tips the balance and locks out. It could be low refrigerant, A bad TXV or the antifreeze levels. The ONLY way to know is to get a GOOD tech out to perform a Heat of Extraction/Rejection (HE/HR). That will tell the tech if the unit is working within specs. Have the antifreeze levels checked. Lastly, superheat/subcool levels should be checked. This will tell the tech if the system's charge is correct or if the TXV is the cause.
Bergy