New York Tranquility 27 fine tuning

Rgausman - very interesting (in its simplicity) flow meter. Thanks for the pix and sharing. We're your WEL numbers from stage 1 or 2 operation?

Sean5545 - I've got the TS (split) 049, but your data points are helpful for pointing me towards where to look for mine. I don't have refrigerant gauges, but considering my unit is only 14 months old and advice given is to check pressures only if necessary I may have to assume all is ok there. Thanks!

Curt - I really want that job! Potentially 2 feet of snow hitting NY tomorrow night. When can I start? Palm trees and geo... Aahhhh... But seriously, I took voltage, current, and air temps today, but all in stage 1. Should my calcs be done in stage 2? Regarding total airflow, my tstat does not allow adjustment of CFMs for stages, so would I use the default values published in the manual?

 

Stick,

The numbers were in stage 1 which my HP runs about 98% of time until we get into the teens here in Virginia. Attached snapshot of the system running in stage 2. My Fluke 337 clamp meter was reading a 0.5 amp (20.6 A) more that the WattNode that is permanent installed.

To answer Pfer question, took the following measurements with a Fluke 337 without doing PF correction...

Stage-1. Stage-2
Compressor: 10.8 A. 14.3 A
Pump, 2x 26-99 2.0 A. 2.0 A
Pump, DSH. 0.4 A. 0.5 A
Fan etc. 1.2 A. 3.8 A. (S2 Believe higher duct static pressure were returns are panned)
------------ -------- --------
Total Amps. 14.4 A. 20.6 A

Measured volt. 248 VAC. 248 VAC. (Recheck VAC with Fluke 87 and it was 246 VAC)

Bob G.

 

It's perfectly OK to collect and analyze data / perform an energy balance in stage 1 vs stage 2. Just be sure the system doesn't upstage or downstage while you are taking measurements.

I don't know CM equipment, but somewhere (not at the thermostat) there is a a setup for airflow - CFM per ton or variations on that - jumpers or dip switches. Install manual probably available at CM site.

 

I've got my air temp sensors in place, and have been making some observations. My performance still seemed to be a little sub-par, then it hit me... Manufacturer's performance chart that I'm looking at is for when DSH is NOT active. Mine has been on the whole time! Can I just toggle the switch off for testing and turn back on when done? Also, I am not seeing much of any increase in LAT when compressor is in stage 2 vs. stage 1. Should I be noticing a difference there?

Thank you!

 

Power down the unit before moving dip switches. Turn off the DHW pump and do your tests.

 

Stage 2 increases CFM so leaving air temp will be relatively constant.

 

Sorry for the delay in following up. Life just keeps getting in the way...

Regarding my airflow, I checked with ClimateMaster on how to determine what my CFM settings are, as I don't have a communicating system (where I could set CFMs through the tstat). They said it's addressed with a service tool, which is $400+, and it's not something I feel comfortable about hooking into my air handler board. I don't remember the installers ever hooking in this tool or spending hardly any time measuring airflow anywhere. Would you suggest that it's OK for me to use the default CFM values from the manual, or should I try to do a little better with something like this http://www.amazon.com/Pyle-PMA90-An...1423675304&sr=8-1&keywords=air+velocity+meter?

Regarding my LAT, I positioned the temp sensor after the coil but BEFORE the fan. Great idea (or so I thought) from an access point of view, but sure doesn't help sensing temp when aux comes on. DOH! Will move to proper location ASAP, and then hope to report back with some findings.

 

This would suite your purposes - http://www.amazon.com/AAB-ABM-100-Airflow-Anemometer-Android/dp/B00MWAGX2U

 

Sweet! With any device of this nature, am I correct in assuming I should take readings at all registers and add them up to give me my CFM value?

 

Yes, there is some math involved, but I believe this has a built in algorithm that will simplify it all for you. You will need to put in register dimensions and such though.

 

Nice toy. I use the same thing that hooks to my main electric meter. Does it do temps?

If you buy it be prepared to do the math. The only thing that helicopter point spinning measures is the flow through the blades. Maybe a 2" circle?

Mark

 

I'm back to concentrating on the source side, now that I have a working speed selector switch for my 2699/3 pump. Strange observation - at any of the 3 speeds I get different pressure readings but I always get the same pressure drop, 2 psi. This would suggest that the flow rate is the same. Am I missing something here? I am working with an analog gauge, (the one referenced on this forum) but am reading it as accurately as possible.

 

If your pressure delta and your loop temp delta remains the same, set it at the lowest speed

 

Loop temp delta decreases (6F on high, 10F on low) at higher speeds, and incurs higher power draw. Which way would you go? I'm focused on this because according to ClimateMaster, for my 4 ton split I should have either 2.25 gpm per ton or 3 gpm per ton flow. I'm calculating 8 gpm total flow. Cause for concern?

 

If I had a 10*F delta with the compressor in second stage I would not be concerned a bit. But since you have a cool monitoring system you may want to note the increased amp draw of the compressor when the pump is on low speed, then compare it to the the amp draw of the compressor when the pump is in the other speeds.

GPM is best measured with a flow meter on B&D flowcenters, Your installer can't come by and note each speeds GPM for you?

 

My installer is out of business. I do have WEL, but not with power metering. I'll work with my clamp meter. Out of curiosity, why is amp draw greater at slow pump speed and, presumably, vice versa?

 

Clamp meter should get the job done. Your compressor will draw more based on the LWT being 5 degrees colder. It has to pump the heat a greater distance up the scale( from your LWT to your EAT) this will require more energy.

 

"Your compressor will draw more based on the LWT being 5 degrees colder."

Nope - Compressor will actually draw less current because it is moving less refrigerant mass. (Decreased suction inlet density) Check extended capacity tables to verify this...power draw falls with decreasing EWT / LWT. Reduced loop fluid flow rates at same EWT reduce compressor power. COP drops, runtime increases. The reduction in power draw is more than eclipsed by increased runtime to maintain a given average rate of heat transfer.

"It has to pump the heat a greater distance up the scale( from your LWT to your EAT) this will require more energy."

Yes and no...greater lift decreases COP so requires more energy to move a given amount of heat. Adding lift by decreasing low side temperature decreases power, COP and rate of heat transfer. Adding lift by increasing high side temperature (for example by reducing CFM / ton or increasing temperature setpoint) increases power, decreases COP and decreases rate of heat transfer.

The differences are subtle but worth understanding, IMO.

 

Thank you gentlemen. I'm trying to keep up with you! At this point, I would like to make a decision on pump speed. I have low/med/high to choose from. Given the above from Curt and Mark's feeling that my single 2699 is borderline for my 4 ton system, is it safe to say running on high is my best option?

"The differences are subtle but worth understanding, IMO."

I wholeheartedly agree. It's still mid-thread, but thank you all for your contributions! The education I'm gaining here is appreciated, valuable, and I firmly believe it will help me maximize the benefits of my investment.

 

And these fixed 3-speed pumps are not as useful as one would think.

Last I had looked, the high speed is just the same as a fixed speed circulator of the same model. The other numbers just being lower %'s.

When you size a pump, you generally are not sizing for the medium speed of a fixed speed circulator. Not on one that has to be manually adjusted anyway. So 99% of the time, you're looking at high speed as the setting.