There is a buzz around here that the government is either giving an incentive or requiring commercial pools have 3 speed pumps. I have not been able to nail it down yet but my first question is, has the health department rescinded the rule that the pump shall run at the rated speed 24/7?
My next question is why 3 speeds?

The pool company who says it is true is clueless as to anything about it.

First I heard of that Greg. Maybe it's in an Energy Code?

I have done some digging and this idea came from California. It is certainly the energy code there. The question is whether this is a federal law, an incentive rebate or just a rumor that a pool company guy embraced to make some extra money. The pump is about 2.5 times as much.

Judy is going to check with the pool (health) inspector tomorrow to see if it is even legal on a commercial pool. That would be my first concern because that guy can throw a red tag and shut you down. You certainly would not want to be several hundred dollars into this and find out you still have run your pump at high speed all night anyway.
If they can find a compromise I can see how this would save a boat load of money. These pools are only licensed to operate during daylight hours.

I'll ask our Health guru today.

Greg:



I checked through the current versions of CEC Title 24, Part 6 (California Energy Code) for reference data per the above quote.
The requirement is only for Residential Installations, and the Motor is to be minimum of Two Speeds (Details are pasted below).

The Regulation(s) are located within Chapter 5 (Mechanical) of the 2008 "Residential Compliance Manual", along with the "Appliance Efficiency Standards".

Below are snips from 2008 CEC T24 Part 6...


Text From 2008 CEC Title 24, Part 6 Appliance Standards:


(5) Residential Pool Pumps.

(A) Motor Efficiency:
Pool pump motors manufactured on or after January 1, 2006 may not
be split-phase or capacitor start – induction run type.

(B) Two-Speed Capability;

(i) Pump Motors:
Pool pump motors with a capacity of 1 HP or more which are
manufactured on or after January 1, 2008, shall have the capability of operating
at two or more speeds with a low speed having a rotation rate that is no more
than one-half of the motor’s maximum rotation rate.

(ii) Pump Controls:
Pool pump motor controls manufactured on or after January 1,
2008 shall have the capability of operating the pool pump at least two speeds.
The default circulation speed shall be the lowest speed, with a high speed
override capability being for a temporary period not to exceed one normal cycle.

..................................................................................
..................................................................................


Text From 2008 CEC Title 24, Part 6 Residential Compliance Standards:

Article 5.2.9 (Mechanical)

5.2.9: Pool and Spa Equipment

Pool Pump Requirements:

For maximum energy efficiency, pool filtration should be operated at the lowest
possible flow rate for a time period that provides sufficient water turnover for
clarity and sanitation. Auxiliary pool loads that require high flow rates such as
spas, pool cleaners, and water features, should be operated separately from the
filtration to allow the filtration flow rate to be kept to a minimum.

All pumps and pump motors shall comply with the specifications of the Appliance
Efficiency Regulations.

The pool filtration flow rate may not be greater than the rate needed to turn over
the pool water volume in 6 hours or 36 gpm, whichever is greater. This means
that for pools of less than 13,000 gallons the pump must be sized to have a flow
rate of less than 36 gpm and for pools of greater than 13,000 gallons, the pump
must be sized using the following equation:

Max Flow Rate (gpm) = Pool Volume (gallons) / 360 min.

These are maximum flow rates. Lower flow rates and longer filtration times are
encouraged and will result in added energy savings.

Pools with auxiliary pool loads must use either a multi-speed pump or a separate
pump for each auxiliary pool load.
For example, if a spa shares the pool filtration system, either a multi-speed pump
must be used or a separate pump must be provided to operate the spa.

If the pool system can be served by one pump of less than 1 total-hp in capacity,
the pump may be single speed.

Filtration pump motors with a capacity of 1 total-hp or more must be multi-speed.

All pool pumps sold in California must be tested and listed with the Energy
Commission according to the Appliance Efficiency Regulations.

Pump manufacturers must list flow rate, power, and energy factor at each of three
system curves (see Figure 5-3).
"Note: Figure 5-3 not included with this text." S.E.T. 07292010

For pools equal to or less than 17,000 gallons, a pump must be chosen such that
the flow rate listed for Curve A is less than the 6-hour turnover rate.
For pools greater than 17,000 gallons, a pump must be chosen such that the
listed flow rate at Curve C is less than the 6-hour turnover rate.

.......................


Pool Pump Controls:

Pool controls are a critical element of energy efficient pool design. Modern pool
controls allow for auxiliary loads such as cleaning systems, solar heating, and
temporary water features without compromising energy savings.

§114(b)
A time switch or similar control mechanism must be installed as part of the pool
water circulation control system that will allow all pumps to be set or programmed
to run only during the off-peak electric demand period and for the minimum time
necessary to maintain the water in the condition required by applicable public
health standards.

§150 (p)1
Multi-speed pumps must have controls that default to the filtration flow rate when
no auxiliary pool loads are operating. The controls must also default to the
filtration flow rate setting within 24 hours and must have a temporary override
capability for servicing.

..................................................................................
..................................................................................

< END OF SNIPPED TEXT >

Scott

Thanks Scott. That makes sense.
Is there an exception for solar PV operated pool pumps?
That is the one thing on the PV biz that looks particularly attractive to me.

Greg:
Answer from Health...
"Camille/John,

The requirement for filtration of commercial pools is that the water be filtered 3x within a 24 hour period.

This might be accomplished via the method described to you however the second requirement is that there be a continuous means of disinfection (auto chlorinator) and this cannot happen without the filter pump running.

End result: Filter must run 24/7.



Hope this helps.Officials name & title deleted due to lack of permission to publish.

To be continued....

Second reply seems to lead me to understand IF the sanitation can be maintained with a slower speed (by increasing the sanitizer) it would be OK with Health.

Guess it boils down to water samples?

Hope this helps

I suppose the real answer is in what the calculated turnover is with the existing pump. I believe the design spec is every 6 hours. If that is the case you could run it 12 hours at normal speed (2 turnovers), and then run it half speed for 12 hours to get the 3d turn over. I am still not sure why they say 3 speeds.

Thanks

Greg,
Not sure if I should be saying this, but I'd like to play the VSD card here.
Most VSD's have options to turn the motor on or off at a given time, with a simple induction motor.
My question is, why complicate things why a 3-speed motor?

Mike:
Formula...

3 speed motor = 'boat load of money'??

Not to rain on the legislators' parade - regular readers will know that I think code-writing has run amok, and that the 'energy' codes are among the worst offenders - Having a pool filter system supplemented by modern controls can really save energy.

Indeed, from the comments so far, it appears that other codes have obstructed the market from addressing this fact.

I've seen the most basic solar collectors make a huge difference in pool heating costs. Remember, as you circulate the water you are also often heating it!

Likewise, codes seem to assume that chlorine is used to sanitize pools. Perhaps this was once a fair assumption - but these days, ozone generators have largely replaced the traditional systems.

I can see merit in multi-speed or speed-controlled filteration arrangements. Let's look at the traditional chlorine arrangement for a moment ....

Chlorine is depleted, in greatest part, by simple sunlight. I suspact that if you had a photocell increase the flow during the daylight hours, you would be adding chlorine as you needed it, and be better able to maintain an even concentration.

Likewise, timers could be used to give the pool a 'power filteration' just before opening time, or to increase filtration during the busiest hours. I think this woiuld be a real improvement over the simple 'on/off' systems we now use.

Lest anyone misunderstand me, I truly wish that code writers would step aside and let the market, and technology, take their natural course. Nothing encourages conservation better than the monthly electric bill!

Like John pointed out, a commercial pool has to run 24/7. The only wiggle room seems to be in the speed of the pump, bearing in mind the 3 turn overs a day rule.
I wonder how much excess capacity a system would have if it was designed for 24 hour service. I also wonder how much the health department would be willing to accept when you started slicing that spec too closely. If the design turnover rate was once every six hours, do they want to err on the safe side and want you to run it longer to deal with the system degrading with age. (filters become less efficient, pipes may scale up and the pump will wear).
The only way I see this really saving energy is if the system was over designed in the first place and you were turning the water over 4 or 5 times a day.

My wife is looking up the specs on the system as we speak to see what they can do.

BTW this is new Florida energy legislation coming up in July 2011. I am trying to find the bill.

This is it and it seems to only be residential pools.



I am still not sure how this saves energy over just running the regular pump for one turn over and shutting it off, which is what most pool timers do.
Mine runs about 6 - 6.5 hours unless the solar heat is on and then it shuts off when I am not getting any solar gain (after the base cycle).
If I had a 2 speed pump I would run it at low speed when the solars were working and after I had the required turnover, just the opposite of the law.
You don't need much water moving if you are just extracting heat from the collectors.
Politicians always want to fix something that ain't broke.

Greg .. please tell me someone is joking!

I'm not sure there are any single phase motors left that you would be allowed to use - and to what end? And what is this 'default speed' gibberish? Looks plain to me they're trying to mandate 3-phase motors on a 1:3 phase VFD.

As you point out, the solar collectors would be served with a slower, rather than higher, flow rate. Perhaps whoever wrote that was looking at a 1750 rpm centrifugal pump curve, and assuming collectors atop a two-story house!

This reads more like a 'product specification' written by a salesman to eliminate the competition from the bidding.

While I'm all in favor of good design, I'm all against litigating it into our lives.

John.,

That comment that is not a joke anymore we are facing the same issue in France as well there are talk about using triphase motor with VSD on it and yeah the single phase motor is slowly drop out of favour as well we have simauir goofy regulations as you guys have now.

So, ya are not alone with this one.

Merci,
Marc

They are still trying to figure out what this really means if the non-response I am getting from the Fl IAEI is any indication. It is probably another thing that will be ignored until midnight on June 30 next year and then everyone will go into crisis mode trying to sort it all out.

Sounds like what I'm hearing from EC's with 'what the hexx do you mean bond the water'.

Back to this subject. Something to what Reno said about the disenfection (chlorination) is in my head. IF you run the pump slow for a period of time, while increasing the chlorine mix, could you not provide a 'sanitized' pool?

Our pools (NJ) for the most part a seasonal, Memorial Day to Labor Day, except the indoors at the hotels and college. It may be a long time cming for the speed controled motor to get here.

There are two issues. Sanitizing is just maintaining the chlorine level. The other issue is actually taking that water through the filter "X" times a day. The chlorine will kill the microbes but you still need to get their dead bodies out of the water or they decompose and you get algae growing. It also makes the water cloudy. Commercial pools also have a turbidity standard. You pretty much have to be able to make out the slots in the screws holding the main drain cover on from the deck.

A high speed pump cycle would be nice to be able to accellerate filtering to clear up algae or other water quality issues. Energy standards would come into play so that the pump would normally run at low speed for normal filtering, and only run at high speed when required to.

So you are saying that you are not slowing the pump down to save energy, you are adding a high speed you don't usually use? That is a whole 'nuther thing.
Pools are usually designed to turn the water over x times a day and in a residential pool they just turn the pump off when that is done with a timer. I am still not sure how a multi speed motor running at a fraction of full speed uses less energy that a pump that is turned off.
Since a commercial pool is required to run all the time, they select a pump to get the required turnover number in 24 hours with a little wiggle room for inefficiency gain as it ages.
The real answer should be in the paperwork submitted when the pool was permitted. There should be flow rates based on the suction and pressure readings at the pump. Then you look up the pump specs for the rate.