Ohio How can you tell it is running in stage 2?

Ok, title might be misleading but I am looking to see if I should be able to hear a difference in the compressor from stage 1 to stage 2. I have a Climatemaster TZ22 installed in the new house in 2014 and when it kicks in to stage 2, the only difference I can tell is that the blower speeds up by 300 CFM.

The LAT in stage 1 is usually in the 97-100* range but when stage 2 kicks in it drops to about 88-91*. To me it seems like it is not generating any more heat, it is just blowing harder. The compressor doesn't change audibly but I am not sure is should....

What should be noticeable when it kicks into stage 2 besides blowing harder? Honestly, it is awesome in stage 1 and then as stage 2 kicks in, it causes more air movement with cooler air and doesn't ever get it up to temp, making it less comfortable. This morning is a good example, stage 1 held on for quite a while but then dropped to the threshold where stage 2 kicked in before I left for work (7am). I stopped home at noon and it had only come up 1 degree despite outside air coming up 15 degrees and the LAT was 86.7 according to the thermostat.

Any insight would be appreciated. Thanks!

-E

 

Eric:

The way to "see" or "hear" a motor working is with an amp meter.

Mark

 

97-100F are some high temps for stage 1 is your blower at the lower spectrum for stage 1 CFM? Best test is an amp meter. Almost sounds like the thermostat is wired backwards runs in stage 2 but its actually in stage 1 according to the thermostat. Dont know if that is even possible though.

 

moey, what would the optimal LAT temp be for stage 1?

Yes, it is set to the lowest CFM (1200 for stage 1) so I know I can decrease that LAT by increasing the CFM for stage 1 as long as I know what we want that to be. I know Mark and I worked on it last year but being a new system at the time, it is probably working more efficiently now that it has settled in (ground loops), plus, to be fair to Mark, we made the configuration changes when it was -10 degrees in the middle of Feb after it had been -10 to -20 degrees all week. With us having a more normal winter this year, the system is operating really well but the heating settings we made last year may not hold true now in year 2 of it being in place.

Mark,
I vaguely remember you saying maybe +25 degrees or so from the EAT, is that a more accurate number? I checked it the other day and my air temp at the filter was somewhere bouncing between 67-68 degrees telling me I can speed up the blower to drop that temp down a couple degrees. That sound like a true statement or leave it where it is?

 

Oh, by the way, I "reset" the system the other day when it was blowing 86* on stage 2 by turning it off at the t-stat and then powering off the breakers for a minute or two. When I brought it all back up and after a little time, it was up to 91.6* on stage 2.

I have had that happen in the past where I needed to power it down and bring it back up, usually after a power outage where it basically crashes the system. Being an IT professional, I usually try that proper power up method on everything before I start troubleshooting for other problems..... It might not be necessary but it seems to work!

 

I have eaten a life time supply of pain killers since we went over your machine, so if I did not write it down the data is lost.

I would still have you find a cheap clamp on amp meter. It will give you a look at how much work the compressor motor is really doing.

Mark

 

Copeland two stage compressors exhibit very little noise change between Y1 and Y2. At the transition there is a click as a solenoid triggers a bypass in the refrigerant circuit.

I echo the recommendation for a cheap clamp amp meter. You'll know right away - 40-50% change in current between y1 and y2. LAT should drop in Y2 only if the CFM / ton ratio is higher. Another possibility is a return air leak that gets worse at higher blower speeds. Check EAT in both stages.

 

Thanks Mark and engineer! Here is what I have seen the last two days with the temp dropping close to zero:

5 ton unit
Stage 1: 1300 CFM producing LAT of 93.5*

Stage 2: 1550 CFM producing LAT of 87.5*. I have to keep it that low in stage 2 or else it just keeps dropping the LAT to where it is not blowing warm air anymore.

When it goes to stage two the EAT doesn't really change so no cold air leaking in. My pump speed remains the same only after jumping up for about 30 seconds and dropping back. Despite my water temp delta T being set at 7, it is only getting 4.5-5 delta T on EWT and LWT in both stage 1 and stage 2. The 87* air on stage 2 is causing it to feel cooler since it is moving the air more at a much lower temp. I have always suspected stage 2 of not working very well because it seems to either maintain set point with stage 1 or stage 2 is short lived and it goes to aux heat not long after stage 2 kicks in. Stage 2 rarely if ever does anything more than maintain the temp at which it kicks on, it never increases the temp back to the t-stat set point unless the outside temp rises to where stage 1 is capable of maintaining it.

Could this be an indication of low refrigerant, just not being able to extract enough heat? I wouldn't put it past my installer to have never even looked at or checked the refrigerant when it was installed.

 

I know what you do and where you live.

Do I need to stop by? I have moved to just north of Celeryville, in Willard. Before all you all's laugh, Google Celeryville, Ohio.

I have had my hands on that machine and did not notice any faults when we changed the DHW piping.

I am not under warranty, but I am fair.

Warm regards,

Mark

 

Based on the fact that there is no increase in water delta T I'm betting the compressor isn't going into stage 2 but that the blower is speeding up, with predictable drop in airside delta-T.

Beg, borrow or steal a clamp ammeter.

 

I am wondering what all issues I am having with this system..... Here is what I have experienced recently:

I have heard the compressor shut down mid cycle while the blower continues to run and it is NOT to temp. The t-stat does not indicate any faults which I would think it would if the compressor is shutting down in stage 1, why else would it kick off?

My Delta-T on EWT and LWT is dropping despite the programming telling it to run at a Delta-T of 7*. I noticed this as it approached 32* LWT even though the JW3 is clipped on the board (running antifreeze solution which allows 10*, not 30*+). It will run the set Delta-T if the EWT is 39* or above.

Stage 2 is pretty useless unless I want to just maintain 69*, it just blows harder and cooler.....

I have a different Climatemaster installer coming out tomorrow, he is the only Climatemaster Elite installer that is close and want the warranty to cover it if it is a problem with the circuit board. Or, if it is the t-stat then that needs to be warrantied too! I just don't want to pay for the service call but sounds like I have to....I need to find our for sure since it is a problem with my system (I think).

 

Compressor shutdown (despite demand) could be normal. See below from DXM2 manual. It should cycle off every 4 hours.

Extended Compressor Operation Monitoring - If the compressor relay has been on for 4 continuous hours, then the control will automatically turn off the compressor relay and wait the short cycle protection time. All appropriate safeties will be monitored during the off time. If all operation is normal, and if the compressor demand is still present, the control will turn the compressor back on

 

Trent is correct. It will make you crazy. We are headed South for a few days I'll be driving by, but forget where you live. Pulling the travel trailer with the service truck from Willard to Lebanon.

Mark

 

Thanks Trent, I thought I had been through the manual completely but I guess I missed this, that makes me feel better! That does seem to be what is happening as it stays off for the 5 min or do safety shutoff period (although I have not timed it).

Now if I can just figure out why the Delta T is dropping and the LWT wont go below 32, I would be much better off! Ideally I don't want it going that low but being a horizontal loop in NE Ohio, I don't have a choice! Its strange, it went below last year and it always maintained the 7* Delta T, just not happening this year! I need to keep an eye on the electrical usage, if it isn't using more than last month then maybe it is OK, but if it is, then I have a real problem!

Mark, maybe when you get back we can take a look? I did call the installer, I want them to fix their stuff if at all possible so I can take advantage of warranty parts if I need it. But, you may see something they don't (I don't have full confidence in them anymore).

 

Actually, I have another question.... If it is running in stage 1, is the delta T that I am seeing (approximately 4*) what it should for stage 1 and if it goes to stage 2 it would climb to 7* with the compressor running harder?

 

Our stage 2 blows in the 94-97F range at 1600CFM. This is for a 5 ton TZ22 same as yours I think. Our thermostat is usually at 70F so return air probably is in the 65ish range I would guess. Just to give you a idea.

 

Moey, I am only getting about 22000 BTU out of it in stage 1, that is about 12000 BTU too low.

Delta T (4) x 11 GPM x 500 = 22000

When it goes to stage 2, it is set for 1500 CFM and at best I get about 88* LAT. I would like to increase it to 1600 but don't want to drop to 84-85 LAT. I am getting 94-97 on stage 1 at 1200 CFM but when it gets cold, like below 10-15 degrees outside and it needs stage 2 help, it doesn't help at all! It really does act like it is not running the compressor any harder for stage 2. I need to check draw on the compressor to see if ti picks up when it hits stage 2....or maybe my compressor needs charged?

 

FYI, here is a picture of the stats on the t-stat a few min after it was in stage 2 (from about noon today). This was forced by upping the set point, not because it needed to go to stage 2. Stage 2 kicks in , Delta T is set to 6*, not even achieving 4*...... The LAT is actually dropping slowly and if I let it run for a while would be in the 86-88* range, it was still warmer from running in stage 1. Stage 1 GPM is about the same as is the actual delta-T but the LAT was around 95 degrees before stage 2 came on. Basically, all of the numbers stay the same between stage 1 and 2 except the CFM and LAT. Sorry for the hard to read picture, it was the best the iPad would do and my iPhone doesn't have a camera.

 

Ok, got a hold of my installer and they are coming tomorrow. When I explained everything I have seen with the system, he is going to try changing the t-stat even though he doesn't think it is a problem. With it calling for stage 2 and aux heat and everything works except for heat production in stage 2, he has a concern that there is a problem with the DXM board or with the compressor itself. Hopefully they figure it out! Even though it is keeping the house comfortable in stage 1, I would like to at least get what I paid for when it gets COLD!

 

Ok, update to my problem.....well, all is right in MY geothermal world now!

I talked with my installer over the phone and he seemed stumped and was set on bad compressor or bad DXM board. He asked about all of the connectors being seated on the board and they were, I had checked all of that already. I verified the thermostat was wired correctly too, all looked good. When asking about the connectors on the board he mentioned the connectors with blue wires for the stage 2 compressor, I knew they were seated. Fast forward to this evening, I came home from work and decided to remove the other access panels just to take a look. When I removed the panel on the left, I could see the two blue wires and plug as well as the the plug port on the compressor where stage 2 power plugs in.....and they were about a foot from each other. The plug and wires were wrapped around the pipes at the bottom of the unit and it had never been plugged in, ever! The year and and a half and all of the eyeballs that have looked at it and you could not see that it wasn't plugged in, not until I took off the panel that is removed to replace or do maintenance on the compressor. I would like to point fingers at someone but the fact is, unless you removed all of those panels and could see the back side of the compressor, you could not tell it was not plugged in.

This whole time it ran on partial power and never kicked the compressor over to stage two, even though it ran in stage two for every thing else. It never faulted and never complained, just never came to temp once stage two kicked in. Also, the air turbulence noise I had has now gone away. Not sure why but it caused the blower to run erratically which Mark and his wife can verify if they remember from a year ago. I am now able to bump up stage 1 CFM to 1300 and stage 2 is at 1650 CFM with no turbulence in the duct work. Stage 1 is blowing 96-97* at 1300 CFM and stage 2 is coming out at 97.5* @ 1650 CFM while still being comfortably quiet.

Needless to say, I am one happy camper at this point. Ridiculously happy! I think I am happier that I am not going to stare at the damn thing wondering why it just doesn't seem right, more than I am happy with its performance now!