UPDATED: Issues with newly installed Spacepak

lukenurn

(This is my initial post. Update is in my next post)

Hi,

My friend and I just replaced our residential AC system (friend is experienced in HVAC, however not familiar with high velocity or Spacepak). Upon powering up, the Spacepak air handler wasn't blowing air. The LCD said "Fan G" - no faults or codes. We left the fan "on" and the cooling "off" with the coil door and electronics door open, came back to the house a few hours later and the Spacepak had kicked on and was circulating. We assumed it was just going through some kind of first start up configuration. It has worked great cooling the home kicking on and off this entire past week.

Today, I was up there adjusting the level so it would drain better and had to turn off the power to the unit. When I turned the power back on, the fan wouldn't kick on again. Same issue as before. LCD screen says "Fan G" when the system fan is "on", and "Standby" when the system fan is "off". I've left it "on" this whole time and it still isn't blowing even though hours have gone by. What's going on?

Details below:

High velocity attic system with an outdoor unit. Both were replaced. Duct work remained.
Spacepak ESP2430J Fan Coil R410A 2-2.5T - Horizontal

I appreciate anyone's advice and help. Thanks!

109A_5

Hello @lukenurn,
Check all fan related electrical connections.
https://skipthewarehouse.com/spacepak-esp2430j-fan-coil-r410a-2-25t-horizontal

lukenurn

Hi @109A_5 . I appreciate your input. I haven't tried your recommendations yet but wanted to share more updates and see if this changes things for you or anyone else.

Oddly enough, the spacepak kicked on just like it did that first day around the same time of day (5:30-6p) then ran smooth thereafter. I didn't change anything.

Now I'm noticing more issues. It ran smooth all day/night but was giving me a "low pressure" signal on the LCD. It's been doing this a few days (see video)

Early in the morning, maybe 2-3:30 a.m. it woke me up because I could hear it almost throbbing high and low, then after a few minutes it became steady and strong like it usually does and ran fine the entire day again. However, it did that throbbing again around the same time last night and woke me up at 3am. This time, I ran up there and took a video of it (see here). I made it call for cooling while up there and you can hear the throbbing and after a few seconds, the LCD flashes "low pressure". This low pressure flashes even when it runs smooth during the day, so I'm not sure if it's linked to the throbbing.

Here are my observations and questions:

• I live in Eastern Wisconsin. Currently upper 70's/low 80's during day and humid, night is in 60's. Refrigerant is full. I have a MERV 13 filter installed due to wildfire smoke.
  
• Why did the fan kick on around the same time in the evening each day after the power was restored (like in my first post)?
  
• Why around the same time early in the morning (2:30-3:30am) does the fan begin throbbing but runs smooth all day?
  
• Is this an electrical issue? It is factory configured to operate on 230V but comes with a line voltage conversion harness to convert to 115V. It's on a double 30A breaker (60A total) and photos of the manual and unit sticker are attached
  

109A_5

Hello @lukenurn,



Wow !!! So was it actually converted to 115 ? I see no date. Hopefully not, I'd verify that very carefully that none of those things in the list were done. The jumper is not installed ? J10 and J12, documentation, and board designation don't seem to correlate correctly, confusing. Also for 230 VAC operation the Breaker should be no bigger than 15 Amp. But that would probably not cause the other issues. Just an overload safety thing.

And you do have 230 VAC going to it ?

I'd check that hose to the pressure transducer (above the LCD display) is connected correctly at both ends and not pinched anywhere.
Does the system know the time of day ?
Fan start temp setting incorrect for your use ? So it stays off until the temperature is in the proper range ?

ratio

It doesn't appear to have been converted to 120, as the white wire from the transformer is still capped off. Also, it's landed on a two-pole breaker ("double 30A breaker"—which is not 60A, BTW). A white feeder wire isn't a clincher, since 240 volts doesn't (very often) need a neutral Sparky just uses plain ol' Romex to feed it. (Should've phased the white wire then, however.)

I think I'd be keeping an eye on the incoming voltage. Maybe it's getting a little out of spec at certain times & confusing the CPU.

Also, double check the low voltage wiring, including the factory wiring. Reading between the lines of manual, I don't think the system is expected to ever see less than 0.1" downstream of the fan. That sensor might be flaking out; or, if it's accurate, you've got a severe air leakage. Either one might explain the hunting (throbbing) you're experiencing, but I can't think of why it would only happen at certain times of the day.

lukenurn

109A_5 said:

Hello @lukenurn,



Wow !!! So was it actually converted to 115 ? I see no date. Hopefully not, I'd verify that very carefully that none of those things in the list were done. The jumper is not installed ? No, I did not convert it to 115. J10 and J12, documentation, and board designation don't seem to correlate correctly, confusing. I think the "line voltage conversion" page I pictured has "J10" mislabeled when it should say "J12". Nice catch. The actual board seems to have it labeled correctly as the lower of the two is for the jump and is empty Also for 230 VAC operation the Breaker should be no bigger than 15 Amp. But that would probably not cause the other issues. Just an overload safety thing.

And you do have 230 VAC going to it ? I believe so. It was an exact swap from the unit 19 years ago that had seen little change. The existing electric and junction box attached to the old unit had those old screw-in round glass fuses: 2 x 15 amp (120 VAC each) so that would be 30 amp (240VAC) total right? We replaced the fuses and junction box assuming those are dated and redundant with the breaker box anyway

I'd check that hose to the pressure transducer (above the LCD display) is connected correctly at both ends and not pinched anywhere.Hose looked good last time I was up there even though I didn't mess with it. Can I just pull it off? I can check it next time.
Does the system know the time of day ?Not sure on this one. I have a honeywell smart thermostat, but not sure if the spacepak can be configured to this. I've included pictures below.
Fan start temp setting incorrect for your use ? So it stays off until the temperature is in the proper range ?Good point. I wonder if the fan stays off until the temp of the coil is correct as indicated by the table below. That's probably why it would kick on automatically in the evening around the same time. The first time we tested it, it was hot in the attic and we had not fully charged the line yet, so the ciol probably wasn't able to get to the desired temp before kicking the fan on. Would that also stop us from running the fan on circulate even if the "cool" is off on the thermostat? Because that is what was happening too. UPDATE I just tried to turn on the system in the middle of the day and received an "antifrost fault" and the fan didn't kick on at all, but the outdoor unit did. My hope is that the fan waited too long to turn on. Any ideas there?

My comments above are in bold.

Do you know what could be causing the pulsing or ebbing of the fan like what has been happening at 2-4am the past few mornings?

Thanks,

Luke

lukenurn

ratio said:

A white feeder wire isn't a clincher, since 240 volts doesn't (very often) need a neutral Sparky just uses plain ol' Romex to feed it. (Should've phased the white wire then, however.)

I think I'd be keeping an eye on the incoming voltage. Maybe it's getting a little out of spec at certain times & confusing the CPU.

Also, double check the low voltage wiring, including the factory wiring. Reading between the lines of manual, I don't think the system is expected to ever see less than 0.1" downstream of the fan. That sensor might be flaking out; or, if it's accurate, you've got a severe air leakage. Either one might explain the hunting (throbbing) you're experiencing, but I can't think of why it would only happen at certain times of the day.

@ratio I appreciate your input. Good point on the double-pole breaker. I forgot about those, and that makes sense because the fuses we removed with the old junction box totaled 30 amps (see my post above I was probably drafting when you submitted your response because I didn't see yours until later).
I did notice that I misread the breaker. Apparently the air handler breaker is a double pole 20 AMP, not double pole 30 AMP as I had originally thought. I'm not sure if this makes a difference

I have a few questions based on what you said:

• What do you mean about "the white wire isn't a clincher - should've phased the white wire then". Is there anything to be fixed here?
  
• If the incoming voltage is off, how do I fix that?
  
• By severe air leakage, do you mean in the vents or main supply downstream of the fan?
  There WAS significant leakage due to small holes and tape coming undone at some of the old joints, but I fixed most of that a few days ago and I'm still getting the low pressure on the LCD. I posted a photo of the troubleshooting in the manual that references low pressure being something related to the board or the little air tube on the board. Just making sure you saw that.
  

Thanks so much!

PC7060

Have you checked the static pressure of the main duct ? Should be in the range of 1.2 - 1.5” WC, preferably right in the middle.  The manual provides details on location of measurement point.  

lukenurn

PC7060 said:

Have you checked the static pressure of the main duct ? Should be in the range of 1.2 - 1.5 ATM, preferably right in the middle.  The manual provides details on location of measurement point.  

Thanks @PC7060 . I haven't done that yet. Right now I can't because I can't even get the blower to turn on. It's doing the same thing as my original complaint. It's hot in the attic and the blower won't turn on, but the outdoor compressor does. After 1-2 minutes, the outdoor compressor shuts off due to an antifrost fault. Could it just be as simple as the blower waiting too long to kick on once the system turns on, so the coil freezes and causes the fault?

Can I just grab a cheap manometer somewhere to check pressure when it's operating?

P.S. I don't have any certified spacepak contractors that service my area. Not sure how to deal with that!

109A_5

When the fan is not running and you think it should be I would troubleshoot the fan wiring to make sure it is the control board that is not commanding it on when it should be on. I would think with the default control board settings it should work, but you never know.

As far as the fan speed hunting is the return side restricted or is there not enough restriction in the supply side ? Since the system can sense pressure, maybe that is how it reacts in certain situations.



BTW The correct over-current device should be used. Keeps the fingers from pointing at you if something bad happens.

A two circuit (ganged) circuit breaker (15 Amps for your application) is just 15 Amps. The two circuit breakers are effectively in series not Parallel since they're on different hot Bus Bars (or should be). The ganged function ensures both hot wires are disconnected if either circuit breaker senses a fault condition.
Also ensures that both hot wired are disconnected when manually shut off.

If a white wire is used for a Hot wire is should be labeled as such per the NEC.

109A_5

This is where you started correct ?

PC7060

I bought this unit on Amazon. Works fine. 

Manometer, RISEPRO® Digital Air Pressure Meter and Differential Pressure Gauge HVAC Gas Pressure Tester https://a.co/d/bP6cAtw

PC7060

The high velocity systems manuals provide critical details regarding main plenum size/configuration and supply line length placement.  Leaks are particularly detriment to keeping the plenum pressure within spec so be sure to seal all joints. I found that the foam seals on the takeoffs tends to loosen and leaks so I cap em with blue can window foam in a can.