Water cooled heat pump

Anthony Mobilio_3

Did a change out today for a friend, lives in a small condo.
1.5 ton packaged unit water cooled. The trouble IM having I that the unit isn't heating the house. Went there today and l looked at everything, looks OK the charge is fine but I noticed when I opened the purge valve on return side you can hear water running threw the lines. soon as I shut it off you don't hear the water going threw the line. The return line seems to be off some where. is there supposed to be constant water being circulated threw the system and with some temp. so the expansion valve can take on some heat.

don_9

need to check

More,what is your delta t on the water side you should have about 7 degree diff from water in to water out.That is assuming that you have 4to 5 gpm thru coil,On the airside
around 30 degree delta t again assuming the proper airflow across coil.What is the super heat and subcooling temp?
By checking this will tell you how well your refrigerant is in the system and how well you're are using the coils.Most
likely you my be hearing a vaccum thru the return when cracking the valve.Is there a 24 volt water valve or a
pressure switch controlling the pump? If you have no water going thru the coil' the coil will began to freeze and kick out on safety.Hope this helps

Anthony Mobilio_3

There is no valve controlling the water. It has a continuos circulation of water. There are 2 lines going into the unit. There is water going to the unit. I removed the lines. The supply line is pumping cool water threw it. (into the in on the unit) the return side it seems like there is a valve shut off. Its not going back to the basement were the pumps are. Should there be some temp. to the water because it seems to be 40-50 deg. I used a pump to push air into the return line and it rejects it. It seems to me that something is shut off.

don_9

I am assuming you have a ground system and not a close loop.
If that's the case the return goes back into the ground,that
can be any where.Do you have a hose bib setup? where you can isolate the return and pump out threw a garden hose in
the driveway,if so try that system should run properly.If so you have a bad return well,or you a have water solenoid that not being energize.

Anthony Mobilio_3

There is a hose hooked up to a perge valve on the return side going into floor drain, I assumed it was a drain to flush it out. Then the return is off. So it doesn't need any temp other the water temp feeding the unit, say 40-60 Deg is this OK. Do water cooled units work on that range. I know there is heat down to absolute 0, but this is the first water cooled one I installed. Thanks

Paul_6

They work if

they are purchased as an extended range geothermal heat pump. you may have to check the model number with the rep for your application. a regular water cooled unit won't work with ground water temps. because you are putting the water directly down the drain are you sure the old unit didn't have a pressure regulating valve that would have opened based on the actual load on the evap or condensor coil?

Paul

Anthony Mobilio_3

Paul, the one we took out was the same, it has a coaxial heat exchanger, just a in an out. There is no valves. even when we run the cooling it goes off on hi head pressure, the water isn't returning back. Its stopping the flow of water from the return line. when i open the perge and allow it to drain to the floor drain it stays running(cooling mode)In the heating mode its only putting out 85 deg air. Is there enough heat in 50-60 deg water to heat this. What is a range for the water temp.

don_9

Anthony,You narrow it down to a bad return,good job.I take
it they had a bad return before you got there and did not mention it.That stinks

As paul said you have to beware what equipment you are using,the builder grade water to airs only work on a
50 to 80 degree eft heating and 50 to 100degree eft cooling.
Water temp above and below range and you will have high and low load cond,with safety tripping.

Next time around try going with a low temp system they are
more forgiving with high and low water temps,and low gpm
If you got 55 degree entering air and you are getting 85
out then you are ok,If your temp rise is to low you made try slowing down the fan speed to increase temp rise across
air coil. What are they going to do about the well? around
my neck of the woods you no longer can dump overboard.
Good Luck

Anthony Mobilio_3

Thanks for the help.

Today we removed a section of the wall. Installed a new ball valve. The one i took out was pluged (big time)
Started up the unit, the room temp. went from 50 deg. to 70 in 10-15 min.

Thanks again guys for the help.
Anthony

Anthony Mobilio_3

Thanks for the help.

One too many..