Heat Pump? What the heck is that?

Specific Inspection Topics Inspecting HVAC Systems
1

Here in Chicago that is a foreign word and all I know is they do not get very hot and work kinda like an A/C unit in reverse.

I did a multi unit hi-rise 100 years old with this systen in place.

Here is a picture of what was on the roof.

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Here is what is inside the 100 plus Living Units.

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I know the boilers on the roof are Ajax 25 years old and I know the smaller units with the blowers are Snyder General with serial number J2671502 and Model number V024aegl on this one.

20 amps double breaker to it.

Top sheet metal is to ceiling vents (ducts)

It has freon so where does the hot exhaust go to?

I am used to a main hot water boiler and chiller unit (central) running H20 through an exchanger with blower in individual living units but this has me stumped.

Can someone give me a crash course here on the basics?

2

I don’t see a heat pump, you have a hydronic system, google it, I don’t have time right now to post more.

edit: water source “heat pump” but not typical air source heat pump as we have around here.

3

I am told this is a heat pump system and temp does not go above 85 degrees.
The Head Engineer explained that’s what it is.
Anyone?

The plate shows it holds R 22 .

4

The first pics are of course boilers
The second pic appears to be an air handler for the hydronic heat (think heater core like an automobile - common in some condo construction even today - some manufactures utilize the hot water from a water heater). Perhaps it had an evaporator installed (hence the R22 tag)… but there would need to be a compressor somewhere and refrigerant lines running to the handler. I don’t see any refrigerant lines in the pictures. There may be a heat pump installed somewhere at the property, but your pictures do not depict one.

5

Yeah I do not see a compressor or lines so that is whats killing me.

I do not usually miss much.The Building Engineer comments and being unfamiliar threw my game off.

I know those boilers are heating the water so I just do not see where the heat pump part of it comes in.

Both seller and engineer stated the same thing separately.
There was a schematic that used the term also.

Interesting is that I did not notice a site glass on the boilers.

6

I look at hydronic systems in condos all the time. The a/c is split, so the compressor should be outside somewhere. If you open the panel on the inside unit, you should see 2 coils. One should be triangular for the a/c part, and the other should be flat and look like a car radiator. The two water lines should be going to the flat coil. When I test the condo units, I just turn on the heat and put my hand on the line. When the water pump starts moving the water, the line will heat up in my hand. That is how I know they are working. These units are great for small areas, but anything over 1200 sf, and the water heater has to be turned up too much to handle it.

7

Possibly engineer pulling your leg?

8

Bob, also a heat pump is nothing more than an air condition that can run in reverse. They work good until it gets below 40 and the the electical heating strips kick in to aid in heating. That is all a heat pump is. it is designed to work in reverse and has a reversing valve in the system. This is the basics of one anyway.

9

Bob, one last thing. If it truly is a heat pump. You will have both a heat and emergency heat selections on the thermostat. The em heat is for just turning on the heating strips. If there is no em heat selection then it will not be a heat pump, just a conventional heater.

10

Not a heat pump.

You have a boiler and the two lines are for hot/chilled water supply and return.

R-22 Refrigerant (Not FREON, you need to quit using that word) makes chilled water for a/c cooling.

11

Yep it looks like a chiller bob.

12

I did not see a big chiller unit on the roof.
But thanks since everyone is in agreement.
Call it a brain freeze .

First time since my very first inspection I got stumped like this.
I will post here if something new is found out.

Guess I will start reading about Heat pumps, just in case so this never occurs again as it made me feel like a rookie all over again.

13

that is a water source heatpump, with a circulating water loop, there will also be a cooling tower on the roof. the boilers heat the loop water to maintain say 85deg water in the winter time. sorry for tha caps and limited info I can’t get the cat out of my lap.
most of what I worked on and installed for 14 years, was this type of system.
pm me if you would like more info

14

Ah Hardware
So it is a heat pump type system.
I do not feel dumb anymore,just ignorant.
Bruce I just emailed the report but if you can tell me more about this system and how these boilers interact with the apt Unit it would be great.
email me at bob@homeinspectorpro.com.

I really hate not knowing something.

15

Bruce, where do you see a Heat Pump device in the pics?
I missed it.

Bob posted nothing that indicates a heat pump.

Please post what you have here as well.
Your terms are a bit confusing.
“Water source” (vs. air source) is where the heating and cooling medium is derived.
Water coil (vs. DX coil) is the heat transfer device.
“Forced air” is the distribution type.

I could see that boilers are needed in Chicago to supplement a heat pump because of the region and heat loads.

Not if it is a water source heat pump in a climate zone where supplemental heat is not required. Don’t confuse anyone.

16

Perhaps he found info from the serial number.

17
18

Bob,
Here is a simple version, they can be more complex in design but it all goes back to the basics. In the summer time in ac mode the heat pumps will heat the loop so it goes up to the cooling tower for some evaporative cooling and in the winter the heat pumps will chill the loop hence the boilers to bring the loop back up to operating temp, about 85 deg. The biggest problem was generally when the inlet strainers on the heat pump would get stopped up.

19

Not all heat pumps have the supplemental heat strips installed. In your area it is a necessity due to your low temps though.

20

Thanks Bruce
Now send me the other two pages darnit.

I do not recall seeing a big chiller unit on the roof however.

Brian thanks for the link as I will check that out too.

Glad it may be awhile before I see another of this type system, but want to be better prepared to know what I am looking at.