This is the first of its kind that I have seen and cannot find much info on this particular model. I am basically referring it to an HVAC professional due to age and condition… but can anyone help me with any particulars on this… there are two condensers… 
M/N: 3012 AC
s/n: 301-36948-c90
thanks a lot…
Jeff
Hi. Jeff, hopefully someone will help and maybe answer a question of mine concerning your photo.
Very strange piggy-back set up and I thought there was a standard that said a condensor unit shall have a minimum of 4 feet of unobstructed space above it.
So who helps Jeff out with his question, could you verify mine also.
Thank you
Marcel :)
Here is a web link
You might give them a call to help answer your questions.
This set up is all wrong. The air flow from the bottom condenser is restricited. It may cause the high pressure to rise on hot days and cause either the internal or external relief valve to open causing a charge problem if external.
Hope this helps
I’ve got a call in as well as an email to them… nothing so far… :twisted:
A/C units don’t have relief valves internal or external???
Jeff I don’t understand why you are defering to a tech did you see something that indicated the unit was not performing as intended give me something to work with.
As for the stacking on top of each other totally wrong the discharge air from the bottom unit is discharging into the air intake on the top unit and will create excessive head pressure and can result in premature unit failure.
If the unit was performing as intended on the day of inspection I would simply state the unit needs to be relocated due to excessive temps and be done with it. Make the call your self no one but a moron would dispute your call.
Thanks Charley,
Basically due to the overall condition, no evidence the system has been serviced in years… the building has been vacant for a while, significant debris in the condensor, corrosion, damaged insulation, loose ductwork… etc… plus my unfamiliarity of the system… I don’t see a lot of A/C systems to begin with, much less this being the first one of this type, brand model…
[quote=“jcampbell, post:7, topic:31962”]
Thanks Charley,
Basically due to the overall condition, no evidence the system has been serviced in years… the building has been vacant for a while, significant debris in the condensor, corrosion, damaged insulation, loose ductwork… etc… plus my unfamiliarity of the system… I don’t see a lot of A/C systems to begin with, much less this being the first one of this **type, brand model…/**quote]
Type brand or model does not make a squat they are basically all the same just the name is different. Make the calls as you see them if it needs service say so if the duct work is loose say so if the insulation is bad say so put it in the report. If the condenser needs cleaned put it in the report the more you do this the more confident you will feel about A/C systems. Just remember this BB always has your back
right… thanks Charley…
my point was about this model was if anyone has any history with them,experience… I cannot find out squat about them… I know the thermo pride furnaces are nice little units but have had no experience “history” with the a/c
always a learning process…
I understand your point but my point was there are two big compressor MFG’s Copeland and Tecumseh and your brand name unit will have one of those compressors in it. That is why I don’t get hung up on brand names or history
i see thanks
Charlie,
I can see where you are going as far as conducting an inspection. Check that it comes on. Check filter. and so on. However I install HVAC systems and yes there is pressure relief valves some internal and some external (old systems) before the feds steped in with CFC’s and HCFC’s. When the high pressure on r-22 reaches 500 psi or r-410a reaches 600psi where will that pressure go. The manufacture doesn’t want the system blow up - do they.
The condenser on top has a solid surface bottom which will not allow air flow from the bottom unit. The bottom will not be able to circulate air flow properly and yes it may take some time but there will be a system failure.
This is no different than placing a condenser under a deck without properly above clearance.
I feel that since I have this knowledge that it is good info for the buyer or pre-inspect for a seller.
Not trying to be argumentive but could you post me a pic of a relief valve on a residential unit and we are talking residential here not commercial/industrial. I have observed the weakest point on a compressor which is the terminals blow out from excessive pressure its just bakealite pressed in as a seal.
As for the stacked units yes the bottom of the top unit is solid metal and diverts the air flow from the discharge of the bottom unit straight into the condenser of the top one provided both are operating at the same time.
A compresor only has the given ability to pump a given pressure and when the discharge exceeds that pressure it does not blow the system up it creates excessive heat and the unit shuts down on internal overload or perhaps can blow the valves out of the compressor provided it is not a scroll compressor
Please open this link and read the ad. Clearly states internal relief valve
http://www.auraheating.com/airconditioners.html
Hook up a set of gages and close the low side condenser valve and both gage valves. Turn on the condenser and watch the pressures. Let me know wht happens when the high pressure reaches 500psi
A compresor only has the given ability to pump a given pressure and when the discharge exceeds that pressure it does not blow the system up it creates excessive heat and the unit shuts down on internal overload or perhaps can blow the valves out of the compressor provided it is not a scroll compressor
So what happens with a scroll compressor when it reaches a high head pressure?
Open this link
Page 2 Look at clearances. Min 48" above for proper vent
http://icpindexing.mqgroup.com/documents/086477/42101500101.pdf
As a Master Tech (Retired) you should know this.
Jeff I admit when wrong never to old to learn something have been retired for 6 years and have not kept up with the service updates. I see from your link some MFG are now installing internal relief but will have a hard time swallowing as you mentioned an external relief as that would be in violation of EPA rules in 40 years of service I have never observed an external relief on a residential unit. Commercial industrial yes.
The way I see it a internal releif would have to dump from the high side back into the low side not to the atomphere.
finally got a response from Thermopride… they are going to send me some more information that I will pass along to client… turns out the systems are 1990…