Question about adding a Air Blower

Gupone

Active member
Sep 29, 2019
36
Texas
Are you talking about replacing the pump dedicated to the new spa jets?

@mas985 thoughts?
Thats what I am trying to figure out since it was not plumbed with a air line. Trying to find out if and what kind of pump will give me some pressure out of the new Jets. I would be fine if it came out as hard as the pool returns do and they are on a separate pump
 

Gupone

Active member
Sep 29, 2019
36
Texas
Right I understand that... but did the original jets have venturi returns before the remodel? The ones that are now down at your feet? If they did I doubt they bubble now nor would be able to use it for your new jets. It sounds like they old ones run through a different pump. As I understand it bubble systems with a blower still use a second set of pipes to get the air flow to the jets. but don't quote me on that.
Yes the old jets are on a totally different set up pipes. The air is controlled by a small valve on the top of the spa. So there is a water and air mixture with those jets. The added new ones were never plumbed right because he only ran a water line and used T's to connect the jets to. Only a separate pump that is circulating water is going through the jets.
 

mas985

TFP Expert
LifeTime Supporter
May 3, 2007
12,780
Pleasanton, CA
In your original post, you made this comment:
The issue is that even with a 3.5HP pump, the jets don't put out much pressure / agitation.
I can't tell you if the new pump is going to be better than the old pump without knowing exactly what the 3.5HP make/model# pump it was.

Also, I need to know more about the plumbing that is feeding the spa. Run length and pipe size would help.

With an 8 jet spa, you need flow rate more than you need pressure but both are important.

I can't seem to find any specs on those jets but they usually come with flow rate requirements. If they are 25 GPM jets, you will need a pump that produces 200 GPM which no residential pool pump will be able to do. He really should have put in two loops of 4 jets each and run them off separate pumps. However, if they are 15 GPM jets, then it may be possible to run them off a single pump but only if the pump is large and the plumbing is also very large 3"+. Otherwise, that is not going to work either.

Bottom line, without more details on the setup, I can't make a recommendation.
 

Gupone

Active member
Sep 29, 2019
36
Texas
In your original post, you made this comment:

I can't tell you if the new pump is going to be better than the old pump without knowing exactly what the 3.5HP make/model# pump it was.

Also, I need to know more about the plumbing that is feeding the spa. Run length and pipe size would help.

With an 8 jet spa, you need flow rate more than you need pressure but both are important.

I can't seem to find any specs on those jets but they usually come with flow rate requirements. If they are 25 GPM jets, you will need a pump that produces 200 GPM which no residential pool pump will be able to do. He really should have put in two loops of 4 jets each and run them off separate pumps. However, if they are 15 GPM jets, then it may be possible to run them off a single pump but only if the pump is large and the plumbing is also very large 3"+. Otherwise, that is not going to work either.

Bottom line, without more details on the setup, I can't make a recommendation.
Mas985, I appreciate all your help. I'm doing my best to give you what you need. Its just that everything is so messed up its hard to give you exact answers but I will do my best.

I can't tell you if the new pump is going to be better than the old pump without knowing exactly what the 3.5HP make/model# pump it was.
The 3.5 pump that was on it was a old pump that had 3" in and outputs even though the plumbing is all 2" the PB put in. I think the name on it was SPECK, Don't know the flow rate but can tell you the impeller was messed up. I took that pump off and put a Old Pac Fab Challenger 2HP Pump that he had sitting there on to see what it would do. I can not tell you if that pump has a good impeller. as far as the specs on it, see the pic below.

Also, I need to know more about the plumbing that is feeding the spa. Run length and pipe size would help.
As stated, he ran 2" plumbing from where the pump is to the spa location which is around 100 feet. He tied that plumbing into the spa's new 2"piping he put in for the additional Jets. He only used 2" T's to tie the jets into the 2" PVC.

I can't seem to find any specs on those jets but they usually come with flow rate requirements. If they are 25 GPM jets, you will need a pump that produces 200 GPM which no residential pool pump will be able to do. He really should have put in two loops of 4 jets each and run them off separate pumps. However, if they are 15 GPM jets, then it may be possible to run them off a single pump but only if the pump is large and the plumbing is also very large 3"+. Otherwise, that is not going to work either.
I will try to find out more info on these jets. I can tell you that the Jet insert part just twists into a housing and at the back of it the opening is around 1"
 

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Gupone

Active member
Sep 29, 2019
36
Texas
In your original post, you made this comment:

I can't tell you if the new pump is going to be better than the old pump without knowing exactly what the 3.5HP make/model# pump it was.

Also, I need to know more about the plumbing that is feeding the spa. Run length and pipe size would help.

With an 8 jet spa, you need flow rate more than you need pressure but both are important.

I can't seem to find any specs on those jets but they usually come with flow rate requirements. If they are 25 GPM jets, you will need a pump that produces 200 GPM which no residential pool pump will be able to do. He really should have put in two loops of 4 jets each and run them off separate pumps. However, if they are 15 GPM jets, then it may be possible to run them off a single pump but only if the pump is large and the plumbing is also very large 3"+. Otherwise, that is not going to work either.

Bottom line, without more details on the setup, I can't make a recommendation.
Did some research on the jets. Looks like they are supposed to use a standard Venturi TEE that would require 8-10 GPM for each jet. However, he did not use Venturi by just PVC TEE's
 

mas985

TFP Expert
LifeTime Supporter
May 3, 2007
12,780
Pleasanton, CA
If the jets are indeed 10 GPM, then 80 GPM should have been an issue for any of the pumps that you have tried to date so the issue might be something other than the pump. The 2 HP Challenger is a high head pump and would normally, produce a little over 80 GPM with that plumbing.
 

Gupone

Active member
Sep 29, 2019
36
Texas
If the jets are indeed 10 GPM, then 80 GPM should have been an issue for any of the pumps that you have tried to date so the issue might be something other than the pump. The 2 HP Challenger is a high head pump and would normally, produce a little over 80 GPM with that plumbing.
To be honest, I'm not sure what the GPM might be at each jet. As stated the PB used a 2" PVC Tee to tie the jet housing and PVC pipe together. The hole / opening of the back of the Jet housing is about 1" so it would seem that 1" of water is going through each jet. Not sure how to calculate GPM for this. Ideas?
 

mas985

TFP Expert
LifeTime Supporter
May 3, 2007
12,780
Pleasanton, CA
You can measure the pressure/suction at the pump drain plugs. This will give the total head and then you can look up the flow rate from the pump's head curve. I believe the pump you have is the Challenger CHII-N2-2A.

However, increasing the size of the pump on 2" plumbing will produce at most 20 GPM more or 100 GPM total for a flow rate per jet of 12.5 GPM/jet. Not much more and I doubt you would feel the difference.
 

Gupone

Active member
Sep 29, 2019
36
Texas
You can measure the pressure/suction at the pump drain plugs. This will give the total head and then you can look up the flow rate from the pump's head curve. I believe the pump you have is the Challenger CHII-N2-2A.

However, increasing the size of the pump on 2" plumbing will produce at most 20 GPM more or 100 GPM total for a flow rate per jet of 12.5 GPM/jet. Not much more and I doubt you would feel the difference.
It's CHII-N1-2AE
 

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Gupone

Active member
Sep 29, 2019
36
Texas
That pump is basically the same as the one I posted. It is the single speed version. So performance will be the same.
Let me ask. What about a spa pump? something like 4 HP Waterway Executive Spa Pump: 2" in/out 56Fr-240V it says its puts out 240 GPM on 2" pipe. Just wanted to ask
 

mas985

TFP Expert
LifeTime Supporter
May 3, 2007
12,780
Pleasanton, CA
First, you should not put more than about 85 GPM over 2" pipe especially if the PB used 2" pipe on the suction lines. in fact in most areas, the velocity limit on spa suction lines is 6 ft/sec which would be only 63 GPM. Over this limit increases the chances of entrapment. You can ignore these safety recommendations if you want to but I would not recommend it.

But the other reason not exceed 8 ft/sec (85 GPM) is head loss. The head loss goes up by the square of the flow rate. So almost any pump is going to be somewhat limited by the 2" plumbing and you are unlikely to get much more flow rate. You need to look at the head curve to determine the flow rate you will get out of a pump. I doubt the Waterway would deliver 240 GPM on your 2" plumbing. That is likely the run-out flow rate (right side of the head curve) which can rarely be achieved especially for an IG spa. But I believe that pump is not self priming so that is a show stopper right there.

Post a link to the specific pump so I can check it out.

BTW, according to this, you need 20-30 GPM per jet. Where did you get 10 GPM from?
Read near the bottom:
“Jet strength is weaker than expected.”

Cause: Not enough GPM. Deep Tissue is consistent with current eyeball results but our specialty faceplates use new technology that require higher GPM.
Solution A): Use 1” Venturi tees for best results or improve plumbing efficiency.
Solution B): Use Deep Tissue faceplates for all jets or consider installing less jets per pump.

Also, the PB should have followed installation instructions:

I would force him to redo his screw up.
 
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Gupone

Active member
Sep 29, 2019
36
Texas
First, you should not put more than about 85 GPM over 2" pipe especially if the PB used 2" pipe on the suction lines. in fact in most areas, the velocity limit on spa suction lines is 6 ft/sec which would be only 63 GPM. Over this limit increases the chances of entrapment. You can ignore these safety recommendations if you want to but I would not recommend it.

But the other reason not exceed 8 ft/sec (85 GPM) is head loss. The head loss goes up by the square of the flow rate. So almost any pump is going to be somewhat limited by the 2" plumbing and you are unlikely to get much more flow rate. You need to look at the head curve to determine the flow rate you will get out of a pump. I doubt the Waterway would deliver 240 GPM on your 2" plumbing. That is likely the run-out flow rate (right side of the head curve) which can rarely be achieved especially for an IG spa. But I believe that pump is not self priming so that is a show stopper right there.

Post a link to the specific pump so I can check it out.

BTW, according to this, you need 20-30 GPM per jet. Where did you get 10 GPM from?
Read near the bottom:



Also, the PB should have followed installation instructions:

I would force him to redo his screw up.
Thank you for all that good info. The 20-30 gpm is what is recommended for their therapy attachment head and that would be including air with it. Since I don't have this option on mine, I would be happy if I could get 10gpm out of each jet. I'm not even sure how to calculate to size a pump that might get the 10 gpm per jet. Plus since he basically made a circle with the PVC pipe, how would you get even flow on all jets. As far as getting the PB to fix what he did wrong is not possible. That would require him admitting he made a mistake and he would have to rip into the spa to fix it. He works along and obviously doesn't really know what he's doing.
 

mas985

TFP Expert
LifeTime Supporter
May 3, 2007
12,780
Pleasanton, CA
As I said before, the Challenger you have right should be delivering 10 GPM with that plumbing setup. But I think the jets you have chosen actually require 20-30 GPM per the documentation. The norm for that type of jet is 25 GPM.
 

Gupone

Active member
Sep 29, 2019
36
Texas
As I said before, the Challenger you have right should be delivering 10 GPM with that plumbing setup. But I think the jets you have chosen actually require 20-30 GPM per the documentation. The norm for that type of jet is 25 GPM.
So let me ask you then. If you take the Jet insert out of the housing, there is just a 1" opening for water to come through. The housings where plumbed directly to the 2" PVC pipe. So really it would be like having 8 1" eyeball jet returns. In that scenario, how much GPM per return / jet should be coming out. I am barely getting a trickle of flow coming out. I'm trying to compare it to the type of pressure that comes out of the pool returns.
 

mguzzy

Well-known member
Jul 8, 2015
758
OV, CA
@mas985 What if he number of jets were reduced from 8 to 6 or 5. What that deliver better pressure on the remaining upper jets? I'm sure there is a clean way to cap them. I'm just thinking our loud. My Spa has 4 jets and that seems to be enough.. 8 people in my spa would be pretty cozy ;)
 

mas985

TFP Expert
LifeTime Supporter
May 3, 2007
12,780
Pleasanton, CA
So let me ask you then. If you take the Jet insert out of the housing, there is just a 1" opening for water to come through. The housings where plumbed directly to the 2" PVC pipe. So really it would be like having 8 1" eyeball jet returns. In that scenario, how much GPM per return / jet should be coming out. I am barely getting a trickle of flow coming out. I'm trying to compare it to the type of pressure that comes out of the pool returns.
You should be getting a little over 12 GPM/jet with the jet fittings removed. Keep in mind that when comparing to the pool returns, there are half as many so they will feel ~2x stronger (for the same total flow rate). If the flow from the open spa jets feels like a trickle, as I mentioned before, there is likely something wrong with the plumbing. Perhaps a clog in the return lines. Have you actually run the spa without the jets installed? This can sometimes clear the lines of debris. Also a pressure measurement at the spa pump return drain plug should tell us if there is an obstruction or not. Can you also post a picture of the equipment pad?


@mas985 What if he number of jets were reduced from 8 to 6 or 5. What that deliver better pressure on the remaining upper jets? I'm sure there is a clean way to cap them. I'm just thinking our loud. My Spa has 4 jets and that seems to be enough.. 8 people in my spa would be pretty cozy ;)
Yes, that is one way to increase the flow per jet. But before doing that, the OP needs to make sure everything is working is it should.
 

Gupone

Active member
Sep 29, 2019
36
Texas
Ex
@mas985 What if he number of jets were reduced from 8 to 6 or 5. What that deliver better pressure on the remaining upper jets? I'm sure there is a clean way to cap them. I'm just thinking our loud. My Spa has 4 jets and that seems to be enough.. 8 people in my spa would be pretty cozy ;)
Mguzzy, thank you for your response. When you mention your spa and having 4 jets, do you also have an air mixture with it. If so, that is my problem. The PB didn't plumb for air and I only have water going through them.