FC struggles

[TRUK71]

The pool service company claims to have used 70 gallons, maybe they did, maybe its a typo. We have no way of knowing for sure. Even if it was just 7 gallons, that is still a lot of antifreeze to dump into a 7000 gallon pool.

I asked them about the 70 gallons and they said yes. Another member said it's not physically possible to get that amount of antifreeze into the lines as I would need 4 100 foot lines.

 

[Bperry]

The pool service company claims to have used 70 gallons, maybe they did, maybe its a typo. We have no way of knowing for sure. Even if it was just 7 gallons, that is still a lot of antifreeze to dump into a 7000 gallon pool.

Yea, I remember that. Even 7 gal is excessive.

 

[Rancho Cost-a-Lotta]

TRUK,

In a previous thread, I recall you were trying to diagnose a suction side leak with lots of air entering the pump the basket. Is it fixed? This may be causing inconsistent flow causing your SWG to turn on and off during the run cycle.

As Oly suggested, try bumping up your FC with liquid chlorine. I would do the overnight chlorine loss test (OCLT) with the SWG shutdown. If no significant loss, on the following night, do an overnight chlorine production test. Run your tests at the same time as the OCLT. Run the SWG overnight and calculate FC gain after the morning test. Compare the FC to expected gains from Pool Math.

 

[TRUK71]

TRUK,

In a previous thread, I recall you were trying to diagnose a suction side leak with lots of air entering the pump the basket. Is it fixed? This may be causing inconsistent flow causing your SWG to turn on and off during the run cycle.

As Oly suggested, try bumping up your FC with liquid chlorine. I would do the overnight chlorine loss test (OCLT) with the SWG shutdown. If no significant loss, on the following night, do an overnight chlorine production test. Run your tests at the same time as the OCLT. Run the SWG overnight and calculate FC gain after the morning test. Compare the FC to expected gains from Pool Math.

The air leak is not fixed. Have a meeting with the service manager at my house on thur to discuss the air leak. They're sending out a tech today to check a plate inside pump to see if it has a leak. I did an overnight chlorine test last night with swg off and had a loss of exactly 1.0.

 

[TRUK71]

TRUK,

In a previous thread, I recall you were trying to diagnose a suction side leak with lots of air entering the pump the basket. Is it fixed? This may be causing inconsistent flow causing your SWG to turn on and off during the run cycle.

As Oly suggested, try bumping up your FC with liquid chlorine. I would do the overnight chlorine loss test (OCLT) with the SWG shutdown. If no significant loss, on the following night, do an overnight chlorine production test. Run your tests at the same time as the OCLT. Run the SWG overnight and calculate FC gain after the morning test. Compare the FC to expected gains from Pool Math.

I'll run the production test this evening.

 

[TRUK71]

Question.....is there a number on FC that could damage a fiberglass pool coating?

 

[TRUK71]

I'll run the production test this evening.

FC started at 4.6
SWG @ 60% for 8.5 hours added 3.3
FC tested at 7.2
Seems ok

 

[Rancho Cost-a-Lotta]

Seems ok

Yep.

8.5 hours @ 60% (3.2 oz. of chlorine gas) should raise FC by 3.4.

Your FC increased by 2.6 ppm (7.2 - 4.6 = 2.6).

Factoring in your OCLT loss of 1.0 ppm the previous night, your SWG is producing as expected.