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Bob45
20-02-2005, 08:14 PM
My problem is my personnal HP

I normally leave the air handler fan on all the time. If the fan is off the problem is not present.

Every time the Hp stop is start knocking like pressure trying to equalize and instant pressure drop.

I had 3 techs and York specialist on site they could not settle the problem.

Any good idea

It's a York 2 tons 14 Seer hp with a 5 tons evap coil as recommanded by York.

It doesn't do it either when it is warm outside or in AC mode.

Thanks for the help.

chemi-cool
20-02-2005, 08:36 PM
Hi Bob,

I don't understand completely what you are trying to say but doe's it have a 4 way valve ?

If it doe's then it looks like a problem there. It should be energized at all times when in heating mode.

Will you please try to explain it better.

Chemi :)

Bob45
20-02-2005, 08:58 PM
Hi chemi,

Yes it as a 3 ways reversing valve on it. and yes it is energized in heating all the time. That is not the problem i'm sure of it. The knocking come from the evaporator and the lines.

I don't know what more I can tell you.

It seem to be because of the size of the evap (5 tons on a 2 tons unit) and the fan on (running 850 cfm) that create the problem. To me look more like flashing gas in the evap that would make an instant pressure drop on the hot gas line or pull back the liquid from the liquid line I have no idea. But why it does that I can't figure it out.

chemi-cool
20-02-2005, 09:06 PM
Hi bob,

In first instance, it looks to me that 5 ton evaporator on a 3 ton condensing unit is way too big.

When the out door unit stops and 4 way valve energized, pressure suold equalize slowly unless ther is a problem with the 4 way valve or compressor discharge valves.
Does it use TEV,s or cap tube?

Chemi :)

Bob45
20-02-2005, 09:10 PM
The unit as a TEV valve and York do recommand a 5 tons evap on a 2 tons condenser for these models that are very high efficency.

I really want to settle this problem thanks for your help

chemi-cool
20-02-2005, 09:18 PM
Hi Bob,
Can you give me the model of the condensing unit please.

I've got an idea I want to check with york people over here.

Chemi :)

Bob45
20-02-2005, 09:42 PM
Hi Chemi,

The model of the condenser is E1RE024S06
The evap is my mistake a G1UA048S21 a 4 tons not 5 tons
The TEV is a 1TV0701A with internal check valve

Thanks

By the way do you have any problem with the site. I do. It's always very long and 1 out of 2 I get a blank page cannot load the page or connect to server. But I use high speed internet that normally works properly.

chemi-cool
20-02-2005, 09:47 PM
Hi Bob.

Thanks I will check it out.

Never have any problems. Here?
This is my second home!

Chemi :)

Peter_1
21-02-2005, 08:16 AM
Same for me Chemi.
The explanation of the problem is also for me not very clear, so finding a solution will not be that easy.
We mostly install a bigger size indoor unit then the outdoor unit, this only increases evaporating pressure, dehumifies less but the 'cold feeling' problems are gone then.

What do you mean with 'personal' HP?
Every time the Hp is stop is start knocking...? What do you mean with this?
.. a pressure drop? a HP or a LP drop or both?
3 way or 4 way? I think it must be 4-way.

Cut-in/cut-out pressures of the HP and LP readings?

Bob45
21-02-2005, 03:21 PM
Hi Peter,

Sorry if I'm not very clear.

By personnal HP = my heat pump in my house....

By the HP knocking = banging like bang bang bang in repetition just after it goes off.

I don't know what you exactly mean by the 4-way valve. Over here on heat pump we call the 3-way valve the reversing valve but sure it as 4 pipes going to it.

The problem is exactly this. When the heat pump stop and the air handler fan is still on, it start banging in repetition for approximately a minute or so. I can't really determine were the banging come from because it goes true the lines. Only does that in heating and when the temperature outside is less then 0 C.

The heat pump is a York Model ERE024, 14 SEER, 2 tons condenser with a 4 tons evaporator as per manufacturer recommendation. Run with approximateley 850 cfm of air thru the air handler.
As a TEV valve with an internal check valve so no bypass for reversing action.

Thanks for your concern.

chemi-cool
21-02-2005, 03:58 PM
Hi Bob

Can you get the model of this TEV? I'll bet its a sporlan.

Can you also try to stick your head in and try to locate the sound source. Try arround the TEV.

Chemi :)

Bob45
21-02-2005, 06:17 PM
hi Chemi,

It is as a matter of fact a Sporlan TEV model VGA 43.

But right now I can't stick my head in there because it is not working today because of the low temperature outside. As soon as I can I will do that and get back to you.

Thanks

chemi-cool
21-02-2005, 08:28 PM
Hi Bob.

I could not find the VGA 43 in the Sporlan site.
See if you can find there: www.sporlan.com and let me know.


As a TEV valve with an internal check valve so no bypass for reversing action.

You should have two of these, one at the condenser as well.

I dont like the absence of the check valves. We just might be on something here.

Chemi :)

Bob45
21-02-2005, 09:21 PM
Hi Chemi,

I looked at sporlan site and according to me would be in the litterature section under compact and adjustable TEV with internal check valve but mind you my TEV is not adjustable. ?????

And as far as I know the VGA V stand just for ***** 22 and GA I don't have a clue. This valve came OEM so maybe that is why I don't have any more specs on the valve.

Peter_1
21-02-2005, 09:33 PM
some thoughts, perhaps silly ones...
Isn't it possible that the NRV makes a strange noise when equalizing?
Can it be the 3 or 4 way-valve that makes noise when shutting of when it's de-energized at that moment?

Isn't it the noise of a backwards running scroll compressor?

See Chemi is also afraid of the TEV.

Place the tip of a screwdriver on the TEV when shutting off and hear on the plastic end with your ear (of course with your ear, with your eyes, it will give some troubles).This will work as some sort of stethoscope.

Isn't the 'banging' not going fast in the beginning and then still starving out with larger intervals?

There is not somewhere a shut off valve in the circuit? They can make the same noise when there is a flow backwards.

I don't think the fan unit has something to do with this noise.

Bob45
21-02-2005, 10:47 PM
Hi Peter,

First of all I don't believe in silly thought as my signature says. Hopefully everybody will learn something new with this.

(Isn't it possible that the NRV makes a strange noise when equalizing?
Can it be the 3 or 4 way-valve that makes noise when shutting of when it's de-energized at that moment?)

I don't think so because the reversing valve stays energized all the time when in heating mode whether there is a demand or not but mind you I never verified it. And the reversing valve noise when it switch over I know what it is with the defrost cycle you can't miss it.

(Isn't it the noise of a backwards running scroll compressor?)

Don't have a clue on that one don't know what kind of noise it would make if it's a wissing noise like reversing pressure no that is not the case.

(See Chemi is also afraid of the TEV.)

Yes I really think he is on the right track here. He is forcing my mind to work harder and think, that is the idea..... haha .

(Place the tip of a screwdriver on the TEV when shutting off and hear on the plastic end with your ear (of course with your ear, with your eyes, it will give some troubles).This will work as some sort of stethoscope.)

I knew that but like I said before I can't check it today it's to cold outside heat pump will not come on it is -15 C

(Isn't the 'banging' not going fast in the beginning and then still starving out with larger intervals? )

You are right on that one got and idea????

(There is not somewhere a shut off valve in the circuit? They can make the same noise when there is a flow backwards.)

No, no luck buddy.

But I do appreciate that you are trying with all of that thinking we will find the solution and probably help other people with it to.

Thanks guys

I don't think the fan unit has something to do with this noise.

stan1488
22-02-2005, 07:25 AM
Hello 2 Comments ,
1 Is Liquid Line Pulsating When This Occurs? If So The Problem Is In Accessories Txv Soleniod Check Valve Et C, Known As Liquid Hammer
2 If Not Sonds Like Coil Is Oversized For Compressor And Your Hearing Collapsing There , Basic Boiler Principle
Just My Thoughts Cheers

Peter_1
22-02-2005, 07:51 AM
...If Not Sonds Like Coil Is Oversized For Compressor And Your Hearing Collapsing There , Basic Boiler Principle

tHIS wILL nEED sOME mORE eXPLANATION. wHAT hAS tHE cOIL sIZE tO dO wITH tHIS?iT'S a cOMMON uSED tECHNIC hERE.

wHAT aBOUT tHE cOLLAPSING? wHAT iS cOLLAPSING aND wHAT dO yOU mEAN wITH cOLLAPSING oF a rEFRIGERANT iN a cOIL?

bOILER pRINCIPLE?

chemi-cool
22-02-2005, 03:20 PM
OK Bob.
This is my personal verdict:
The indoor unit is too large, a 2 ton condensing unit with the highest SEER will have the capacity of 2 tons, it will draw less currant and thats what makes it high efficiency. So it is a mistake to install an indoor unit double sized.

the knocking comes from the check valves and if you put your ear near the TEV, you will hear it or better, put your hand on the TEV and feel the liquid knocking.

My solution will be to install an indoor unit with the right capacity.

Add a bypass with checkvalve on the TEV on both indoor and
outdoor .

Chemi :)

Bob45
22-02-2005, 03:53 PM
(The indoor unit is too large, a 2 ton condensing unit with the highest SEER will have the capacity of 2 tons, it will draw less currant and thats what makes it high efficiency. So it is a mistake to install an indoor unit double sized.)

Sorry but I don't believe the indoor coil is to large. I do believe in York International design engineers. They have sold a lot of these unit this way and they work.....

The internal check valve may have something to do with it that is more likely.

My personnal thinking about this is as follow:

The hot gas get into the indoor coil. Drops in temperature and liquifies normal ok.

When the unit stop. The compressor stops feeding the hot gas to the coil. The fan still on get the heat out of the hot gas traped in the coil which make the ***** liquify instantly and create a instant pressure drop in the coil which make the check valve open and close to balance the pressures. Keeps on like that till there is enough liquid ***** in the coil to avoid the pressure drop. What do you think of this senario. Could this make any sense to you.

(Add a bypass with checkvalve on the TEV on both indoor and
outdoor .)

But there is checkvalve inside the TEV which I believe work properly because the unit works properly in heating and cooling so I don't believe that putting and external check valve would solve anything.

Keep going we will get somewhere.

Thanks to you all.

chemi-cool
22-02-2005, 08:07 PM
Hi Bob,

Yes I think that York engineers made a mistake!!! I am sure of this.

You have written that York techs could not solve the problem, so maybesome mistake was made?? ;)

I spoke to my design engineer after I've posted and he agreed and added that for a 2 ton split, it would be better not use a TEV at all but a cap tube, located in outdoor unit.

That will eliminate all the noises.

Chemi :)

chemi-cool
22-02-2005, 09:45 PM
Just found this pdf.
If the inormation in it is true, then your indoor unit is also 2 ton and not 4.

http://www.rev.gov.bc.ca/ctb/publications/EnergyStarLists/List_2005feb_SplitSystemHeatPumps_EnergyStar.pdf

Scroll down to page 22 and see for your self.

Mayby they gave you a 4 ton TEV?

Chemi :)

Bob45
22-02-2005, 11:03 PM
Hi Chemi,

(If the inormation in it is true, then your indoor unit is also 2 ton and not 4.
http://www.rev.gov.bc.ca/ctb/public..._EnergyStar.pdf
Scroll down to page 22 and see for your self.
Mayby they gave you a 4 ton TEV?)

If you look at what you are telling me to look at you will see that the G1UA048S17 is on there spec for that unit which 48= 48000 Btu or 4 tons and the outdoor unit is a ERE024 where 24=24000 Btu or 2 tons so that is the design.

Second I always look at a system as it was working before why it is not working now...... These system are sold like this true out the states and Canada in big quantities do you think that if they had a lot of come back on them they would not do anything about it. I don't believe that. They would modify the system accordingly. But that is not the case it does work

And in regard to the TEV valve the indoor valve doesn't work in heating mode in goes in reverse true the check valve and the TEV on the outdoor unit is preinstalled from manufacture. If it would be to big you would get flood back to the compressor???? which is not the case.