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  1. #27
    Join Date
    Aug 2009
    Location
    Prattville, Alabama
    Posts
    1,989
    "Blower unit" indicates BaldLoonie is correct, but that is using the suspect assumption that correct terminology is being used by property manager. If so, must be a chiller somewhere, maybe the basement. Maybe some things are being lost in translation from the property manager to kevk773 to here, but the property manager doesn't seem to be too forthcoming with information. Someone who understands their own system should be able to give a clear, concise one or two sentence description of it.
    Last edited by Nuclrchiller; 01-27-2012 at 09:44 AM. Reason: grammar

  2. #28
    Join Date
    Aug 2003
    Location
    Fort Worth, TX
    Posts
    11,289
    Quote Originally Posted by kevk773 View Post
    Actually I did flip the thermostat cover because I wanted to see if there was anything different function-wise from the one at my rental. I didn't see an "emergency heat" function. That being said I'm guessing from whats been said in this thread that this building has water cooled AC with coils for winter?

    The Realtor confirmed that the heat IS included in the assessments and that I would just be paying to operate the blower unit. The condo is a concrete loft. approx 1250 sq ft with 12ft ceilings, SW corner with a unit above and below. The current owners average about fifty dollars a month for electricity.
    Paying to operate the blower unit, if what I've read in your thread so far pans out, means you would also be paying to operate the heat strips in that blower unit. In summer, your assessment covers the chiller operating costs, I gather.

    Fifty bucks a month ain't bad, but of course that's based on the existing occupant's living habits, not yours. That said, a condo for the same square footage and footprint as a single family house will generally be easier to heat and cool due to several of its walls being common to other units and interior hallways. Individual unit behavior can vary, of course, and also would depend on how the building is put together.

    What you will be faced with, however, is those few days every spring when the management hasn't turned on the chiller yet, but you wish they would go ahead and do so. Many properties drain their cooling towers during the winter to prevent fouling and freezing problems from setting in. So the tower and condenser water loop must be refilled and treated before the chiller and tower can be started for the cooling season.
    • Electricity makes refrigeration happen.
    • Refrigeration makes the HVAC psychrometric process happen.
    • HVAC pyschrometrics is what makes indoor human comfort happen...IF the ducts AND the building envelope cooperate.


    A building is NOT beautiful unless it is also comfortable.

  3. #29
    Join Date
    Jan 2012
    Posts
    11
    Quote Originally Posted by Shophound View Post
    Paying to operate the blower unit, if what I've read in your thread so far pans out, means you would also be paying to operate the heat strips in that blower unit. In summer, your assessment covers the chiller operating costs, I gather.
    Thank you for the feedback. So it wouldn't be the case where the heat strips are on a different circuit powered by the building and the blower on the unit's power? I imagine then that in the winter I could expect a large electricity bill if I am powering both the strips and the blower.

  4. #30
    Join Date
    Jan 2012
    Posts
    11
    OK I got a lot more details in the HVAC system. I've pasted the details below. So I'm assuming because this is not just a blower system, it will cost much more to power the heat pump vs a standard blower? Feedback appreciated from all the Professionals in here.

    There are two separate systems providing heating and air-conditioning (cooling) for the building. All common area hallways from the second floor up get their temperature-regulated air from two traditional forced air units installed on the roof, whereas all residences and the 1st floor lobby get their cooling and some heating from the building wide closed water-loop system and associated heat pumps.
    The closed water-loop system circulates a glycol and water solution throughout the building and subsequently through the heat pumps located in each residence. In the case of the building, the cooling of this fluid is via an open, evaporative cooling tower located on the roof. There is no installed means to heat the fluid.
    Each residence has a heat-pump air-conditioner unit. Within the unit, cooling is accomplished using a high-pressure pump and the standard freon-based expansion/compression cycle. The heat extracted during this cycle is carried away by the water/glycol solution in the closed water-loop system. The heatwater/glycol is ultimately brought back down in temperature by the cooling tower. The resulting cooled
    air within the air-conditioner unit is then forced by a fan through ductwork and distributed about the residence.
    The primary benefit of any heat-pump system is the ability to exchange heat and cooling throughout various parts of a building. One part of a building may want cooling, in which case it would be heating the water/glycol solution, another area may want heat; it then would remove heat from the water/glycol solution. Heat is then “pumped” from one location to another.
    This is not a typical case in the building. Usually we all want heat or we all want cool air.
    Cooling is generally not a problem provided an individual unit’s compressor is working correctly, the system has an adequate Freon charge and the condenser coil is clear of debris. This is true because we have an external means with which to get rid of the heat (the cooling tower). On the other hand, if all residences decided to heat their places using the water closed-loop system then the water/glycol would very quickly get cold (the heat pumps would remove heat from the solution) and no further heating would
    result. Unless an outside source of heat is provided, heating will only occur to a limited extent and this is primarily due to an exchange of heat from one residence to another with only a little heat coming free from the outside. Unfortunately, the lower the outside temperature, the less “free heat” will be available.
    Should the outside temperature fall below a certain threshold temperature (between 40 and 50 degrees Fahrenheit), then your heat pump will need an added boost. This is achieved by turning on an internal electric resistive heating coil within the unit. Therefore, should your residence seem to be not quite as warm as you would like, i.e. the heat pump (in heating mode) is not pulling out a sufficient amount of heat then chances are there is no more heat to be pumped from the water closed-loop system and the internal electric heating must be turned on. This does not occur automatically.

  5. #31
    Join Date
    May 2000
    Location
    Indianapolis, IN, USA
    Posts
    33,898
    Boy, this is pretty rinky dink. Who ever heard of a loop heat pump system with no heat in the loop, especially a residence. So what do they do, wait for the condo units to go out on low pressure due to a cold loop then you manually turn on strips? Wonder how you do that with no em heat setting on the stat?

    Is this in a fairly mild climate where cold temps don't occur often?

  6. #32
    Join Date
    Aug 2003
    Location
    Fort Worth, TX
    Posts
    11,289
    Quote Originally Posted by BaldLoonie View Post
    Boy, this is pretty rinky dink. Who ever heard of a loop heat pump system with no heat in the loop, especially a residence. So what do they do, wait for the condo units to go out on low pressure due to a cold loop then you manually turn on strips? Wonder how you do that with no em heat setting on the stat?

    Is this in a fairly mild climate where cold temps don't occur often?
    I would think the stats are two stage...if the loop gets cold and the pump can't combat the heat loss from the condo by itself, the strips kick on. What I'd also want to know is if there's a low temp sensor on the loop at each heat pump that will lock out the comp if the loop gets too cold. This would serve two things...protect the compressor and allow the loop to warm up if enough condos lock out and go to heat strip heating only.

    Also appears there's a heat exchanger between the tower and the closed loop. And that there's glycol in the loop.
    • Electricity makes refrigeration happen.
    • Refrigeration makes the HVAC psychrometric process happen.
    • HVAC pyschrometrics is what makes indoor human comfort happen...IF the ducts AND the building envelope cooperate.


    A building is NOT beautiful unless it is also comfortable.

  7. #33
    Join Date
    Aug 2009
    Location
    Prattville, Alabama
    Posts
    1,989
    Yep, not impressed. Have to wonder if they do have a heat source - it's just broken and cost too much to repair, especially considering tenants have backup heat (which the tenants pay to operate)?

  8. #34
    Join Date
    Jan 2012
    Posts
    11
    Thanks guys for replying. Here is some other stuff explaining the switchover: @BaldLoonie - This is in Chicago, no mild temp here!

    Should the outside temperature fall below a certain threshold temperature (between 40 and 50 degrees Fahrenheit), then your heat pump will need an added boost. This is achieved by turning on an internal electric resistive heating coil within the unit. Therefore, should your residence seem to be not quite as warm as you would like, i.e. the heat pump (in heating mode) is not pulling out a sufficient amount of heat then chances are there is no more heat to be pumped from the water closed-loop system and the internal electric heating must be turned on. This does not occur automatically. Follow the procedures below before calling in the repairman.
    Winter Procedure (More heating capability)
    1. Lift the cover from the front of the unit (follow the procedure given below for the air filter replacement).
    2. Locate the “emergency” toggle switch (truly a misnomer in this context; unfortunately, they’re all marked this way) on the upper third of the unit and flip it to the on (up) position. This switch merely enables the electric heating coil.
    3. Replace the unit cover and set the thermostat to the desired temperature.
    4. Reset the breaker if necessary.
    Summer Procedure (Less heating capability)
    1. Lift the cover from the front of the unit (follow the procedure given below for the air filter replacement).
    15
    2. Locate the “emergency” toggle switch on the upper third of the unit and flip it to the off (down) position. This will disable the electric heating coil.
    3. Replace the unit cover and set the thermostat to the desired temperature.
    4. Reset the breaker if necessary.
    C. Cooling
    As with the heating, until an external source of cool water is supplied your heat pump unit will only furnish cooling to a limited extent. This cooling off capacity will drop dramatically as the outside temperature rises.
    City ordinance requires that any building in which all or most of the cooling is provided by a central system must have the system ready for use by May 31 of each year. The building has a contract with a company that will “start-up” the water closed-loop system for summer and “drain-down” and
    secure it for the winter months. Building management can, at its discretion, start up the system earlier than required. The contractor responsible for the start-up will be contacted and the system activated
    subject to company scheduling availability.

  9. #35
    Join Date
    May 2000
    Location
    Indianapolis, IN, USA
    Posts
    33,898
    I wouldn't have anything to do with this joint!

    I pictured this place on Florida or something where heating isn't needed. But Chicago to not have loop heat and have to tear into your unit to get on backup is NUTS. Same with cooling, there's lots of cooling needed in May. So if you want cooling and the loop gets too warm, what happens?

  10. #36
    Join Date
    Jan 2012
    Posts
    11
    Quote Originally Posted by BaldLoonie View Post
    I wouldn't have anything to do with this joint!

    I pictured this place on Florida or something where heating isn't needed. But Chicago to not have loop heat and have to tear into your unit to get on backup is NUTS. Same with cooling, there's lots of cooling needed in May. So if you want cooling and the loop gets too warm, what happens?
    According to the docs if I read them correctly, there is actual freon to supplement the cooling in the unit. In otherwords, I guess I'd be paying for most of the heating and cooling in this place since this is Chicago. I'm glad I found this forum! Thanks for the feedback. I will not be purchasing this place.

  11. #37
    Join Date
    May 2000
    Location
    Indianapolis, IN, USA
    Posts
    33,898
    Still can't fathom a residential building with no heat in the loop or insufficient capacity in the tower to cope with summer heat.

    This type of system is common around here in office buildings, old folks homes, etc. I can see steam from the towers in 10 weather in an office. My Dad's last old folks apartment heated with no backup on even to 0 out.

  12. #38
    Join Date
    Aug 2003
    Location
    Fort Worth, TX
    Posts
    11,289
    I guess whoever designed and installed this system for the condo building never heard of:

    a) a boiler, to keep the loop warm during very cold weather

    b) a sump heater for the cooling tower; would allow the tower to be filled and brought online much earlier than May 31st!

    c) building automation controls. Would automatically control the tower so it only runs when it needs to. Can also provide a reset schedule for the missing boiler.

    Yep, I'd pass on this place. Sounds like they're living with a half-butt engineered system.
    • Electricity makes refrigeration happen.
    • Refrigeration makes the HVAC psychrometric process happen.
    • HVAC pyschrometrics is what makes indoor human comfort happen...IF the ducts AND the building envelope cooperate.


    A building is NOT beautiful unless it is also comfortable.

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