I think you're right -- I just need to keep the family from showers/washing dishes while filling (I'll do my part!)
stever said:I think you're right -- I just need to keep the family from showers/washing dishes while filling (I'll do my part!)
stever said:Ok - I need a little advice -- a second opinion - or both. My PB has sketched up (and I put on CAD) the schematic for the pool/spa piping (see first page of this thread). He said he had to do this a 'new' way to get the Intelliflow VS to work as the single pump for a pool/spa combo.
He has both returns and jets for the spa. He said that all 120-150 GPM would not work well through the heater and filter and is routing part of the flow to the filter/heater and the rest to the jets. (I have 3" piping to the jets and from the spa drains).
I just found that the minimum flow for the 400,000 BTU heater is 40 gpm. I don't know how much head I will have in the end, but figure I'll max out the VS at 140-150 gmp. subtracting 45 (a little extra to keep it safe) gpm for the heater, that might only leave 95 gpm (worst case??) for the 8 jets -- that's 12 gpm per jet or 20% less than the 15 gps per jet I was told I needed.
I can give you a rough guess as to your head and flow rates but I need some more information see the questions at the end.
- Is it typical to have seperate returns and jets to the spa?
My pool is plumbed that way and it is usually a good way to get higher flow rates for the jets.
- Will I have enough flor for both the heater and the spa jets?
Possibly but I can give some numbers with the additional information.
- Is there a better way? How are yours plumbed?
My jets are on a separate pump and suction lines. It usually is not a good idea to have very high flow rates through a filter and heater. Filters are less efficient and heaters usually have an upper limit of 120 GPM after which they require a bypass. The configuration in the drawing is probably the only way you will get the full flow rate for the jets.
Thanks!
Steve
JasonLion said:It is not uncommon to have a separate return to the spa, normally used for heating and to provide water for the overflow when in pool mode. This typically happens in a two pump split system, where the pool pump has the heater and the spa pump feeds the jets. Such a system would typically have two sets of drains in the spa, each set feeding one of two pumps but otherwise looking much like the setup you have in the diagram. Heated and filtered water from one pump would return to the spa through a return while high flow water from the spa pump would go to the jets.
I have 1 set of drains in the spa and a one-pump system.
Given your pump and flow requirements it might be better to plumb things more like a two pump shared heater system. In that setup the spa pumps output is split and part of it goes through the filter and heater while part of it bypasses to maintain high flow rates. Then the flow recombines to feed the jets at the full flow rate.
I like that a lot better -- then I'd get the full pump flow to the jets. When the flows recombine they will get the power needed. In pool mode, the returns would be on and not the jets and in spa mode the jets would be on and not the returns.
You don't want the full flow going to the filter and heater. It would be too expensive to get a filter big enough to handle that and even then it would be a waste since you don't need that much filtering and the extra head of the filter/heater would cost electricity.
I agree with this -- I have a 60 sf DE filter planned -- it'd blow up with 160 gpm!
This setup would use an automatic valve to split some of the water around the filter/heater and then recombine the water after the filter/heater. From there another automatic valve would split it again to the pool and spa. All of the spa water would feed the jets, no spa return would be required. In pool mode the filter/heater bypass is turned off and only a little water goes to the spa for overflow. In spa mode the filter/heater bypass is turned on and the pool return is turned off.
mas985 said:stever said:Ok - I need a little advice -- a second opinion - or both. My PB has sketched up (and I put on CAD) the schematic for the pool/spa piping (see first page of this thread). He said he had to do this a 'new' way to get the Intelliflow VS to work as the single pump for a pool/spa combo.
He has both returns and jets for the spa. He said that all 120-150 GPM would not work well through the heater and filter and is routing part of the flow to the filter/heater and the rest to the jets. (I have 3" piping to the jets and from the spa drains).
I just found that the minimum flow for the 400,000 BTU heater is 40 gpm. I don't know how much head I will have in the end, but figure I'll max out the VS at 140-150 gmp. subtracting 45 (a little extra to keep it safe) gpm for the heater, that might only leave 95 gpm (worst case??) for the 8 jets -- that's 12 gpm per jet or 20% less than the 15 gps per jet I was told I needed.
I can give you a rough guess as to your head and flow rates but I need some more information see the questions at the end.
- Is it typical to have seperate returns and jets to the spa?
My pool is plumbed that way and it is usually a good way to get higher flow rates for the jets.
- Will I have enough flor for both the heater and the spa jets?
Possibly but I can give some numbers with the additional information.
- Is there a better way? How are yours plumbed?
My jets are on a separate pump and suction lines. It usually is not a good idea to have very high flow rates through a filter and heater. Filters are less efficient and heaters usually have an upper limit of 120 GPM after which they require a bypass. The configuration in the drawing is probably the only way you will get the full flow rate for the jets.
Thanks!
Steve
I have a full head model which includes the Intelliflo pump. I can usually get close enough to actual flow rates. Most of the plumbing parameters I can get from your drawing but need some additional information to model the pool.
The drawing you gave has the diameters of the pipes but not the lengths. So about how long are the runs from pad to pool, suction and return, pool and spa? Also, are all the lines single lines as shown on the drawing?
One additional concern is that he has used 2.5" plumbing on the spa suction line but 3" on the return lines. The jets will add a lot of head on the return side so there should be more head on the return side but for the high flow rate of the spa, I would have put 3" lines on the suction as well. He probably figured they were short enough not to matter.
stever said:Will the high GPM in the jets try to push the water backwards in the pipes where they recombine? Seems like the 120 gpm would try to fight with the 40 gpm. (but it's been 20 years since I took my hydraulics course.)
mas985 said:By restricting the bypass route, it increases the flow in the filter route. However, the total flow is reduced when you do this. Maybe this will help.
The more the bypass is restricted, the more will flow through the filter.
mas985 said:At 135 GPM, suction head is about 5.8' and return head (with jets) is about 53' of head with total head at about 59. The jets alone are about 48' of head.
JasonLion said:I don't see any reason for the check valve just above the filter.
I show this because I have seen it before in schematics -- but you are right -- once I have one after SWG later in the circuit, it's useless.
You aren't showing the main valve on the filter. The "drain" from the filter is typically called waste and should not have a valve on it (other than the main valve).
Correct again -- I should not call the drain a valve -- it's just 'there'.
You show the main pool drain plumbed to the skimmer. Ideally the pool drain and skimmer should run in separate pipes to the equipment pad, though it will work the way you have it drawn.
Unfortunately I did not know enough about this until it was too late. The main drain is hooked up to the skmmer with a little rotating flappy thing to somehow regulate the flow. I have pretty good piping to the spa but so-so plumbing to the pool (2" to the skimmer/main drain and 2" back to the 4 returns). I'm not too broken up about this as the difference in efficiency will most likely be minor at slower speeds. (plus it't too late!)
mas985 was talking about 100 feet of pipe, not feet of head. They are related in a complex way that makes it simpler to talk in one unit for some purposes and in the other unit for other purposes.
Roughly how do I take this into to the pump charts? Is there a rough conversion factor I can use?