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Posted By: Elmer Pool Heater - 07/06/05 11:31 PM
The pool is ten years old. A new gas fired pool heater was installed. The existing pool pump has no time clock, straight cord connection with a toggol switch. Question is does the pool heater which has a fireman switch to it need to be connected to the pool pump motor time clock which it does not have. Is this a building code of NY. Or just leave it alone and install a disconnect for the heater? By pass the fireman switch ?
Posted By: gfretwell Re: Pool Heater - 07/07/05 03:17 AM
I think that as long as the AC supply to the heater is on the load side of the last pump disconnect you are OK. The purpose is just to prevent heat without pump power. There is also a flow switch in the heater but a belt and suspenders is not bad in this application.
When a timer is involved they want the pump to run a few minutes after the heat is shut down.
I am still not sure I understand all I know about this so I am open to correction.
Posted By: mhulbert Re: Pool Heater - 09/13/05 04:34 PM
You have to run the pump for ~5 minutes after the heater is shut off. Otherwise, the remaining water in the heater boils off and leaves scale and junk in the heater, meaning it won't last terribly long.

The simplest way to arrange this would be a delay to off relay triggered by the pilot controls for the heater. If you have a pool control system (ie aqualink) it takes care of this for youat all times.

mike
Posted By: willfescon Re: Pool Heater - 01/19/08 03:55 AM
I had a service call with a pool gas heater with no rating plate, only a 120/240v blower motor so it shouldnt be more than 2 or 3 amps. The pump is controlled by a timeclock off a 2 pole 25 amp breaker on a #12 wire, and the heater is spliced into the same circuit. The pool man installed all of this himself only to be told by the inspector to call an electrician, get a permit, look it over, and call for a reinspection.

I'd rather see the pump on a dedicated circuit and the heater on a dedicated circuit. The existing timeclock is only a 2 pole so i use the timeclock to switch on/off a 4 pole contactor which controls both the pump and heater simultaneously. Just wondering if I went overkill with separating the pump and heater circuits. I don't think so though.

Posted By: gfretwell Re: Pool Heater - 01/19/08 04:48 PM
You want to run the heater from the pump circuit so the heat can't run if the pump is off. Then you want the fireman switch loop to actually turn the heat off before the pump goes off. Get the manufacturer's instructions for the final answer. They should be on the web.
Posted By: Rewired Re: Pool Heater - 01/19/08 09:52 PM
There is a time clock made by Intermatic ( I think its still made) that is designed for pool pump / heater use. It operates the pump as any normal timer would BUT has a set of contacts that open 20 or so minutes before the actual off set time in order to shut down the heater and allow it to cool with water circulation.

My own pool I do not have a time clock and my heater is all millivolt control.. I went way overkill in wiring mine up using a magnetic starter and 24V pushbutton controls for both the pump and heater, Only because I wanted to add pushbuttons to control the pump and heater from inside the house, out in the shed and from the patio as well. Also the way its wired, it ensures that if someone hits the stop button for the pump OR the power fails, it shuts down the heater at the same time. I have had one too many close calls with the pressure switch sticking closed and keeping the gas valve open with no water flowing!

A.D
Posted By: SteveFehr Re: Pool Heater - 01/22/08 05:15 PM
Originally Posted by gfretwell
You want to run the heater from the pump circuit so the heat can't run if the pump is off.
I have a funny story about that... yeah, back when I was watercooling my computer and, in my infinite wisdom, decided to put the computer on UPS, but plug the coolant pump (120V fishtank pump) straight into the wall. Ever wonder what happens to an Athlon when it runs for 5 minutes without cooling?
Posted By: Retired_Helper Re: Pool Heater - 01/22/08 05:27 PM
Originally Posted by SteveFehr
Ever wonder what happens to an Athlon when it runs for 5 minutes without cooling?


Well done, I presume. frown
Posted By: SteveFehr Re: Pool Heater - 01/22/08 05:58 PM
Actually, it's rather anticlimactic. Processors will run surprisingly hot with no problems, and tend to simply lock up and stop processing long before any permanant damage occurs. And when they do that, they cool back down. I ran that chip another 2 years after that with no problems smile Well, at least not with the chip, the water cooling was another issue. Ever wonder what happens to vinyl tubing if you fill it with antifreeze, surround it with sensitive energized electronic components and heat it to 120°F for 3 years?
Posted By: Theelectrikid Re: Pool Heater - 01/22/08 07:52 PM
Originally Posted by SteveFehr
Well, at least not with the chip, the water cooling was another issue. Ever wonder what happens to vinyl tubing if you fill it with antifreeze, surround it with sensitive energized electronic components and heat it to 120°F for 3 years?


Splash?
Posted By: SteveFehr Re: Pool Heater - 01/23/08 11:38 AM
drip frown The stiffened tubing weeped just a *tiny* bit every time I jostled it to change out a hard drive or add another stick of ram, but I never saw it. Every time I'd inspect for leaks, I'd never find one because it was only leaking under special circumstances. Every time I thought I had it fixed, I hadn't. So, it dripped... right onto my $200 video card, destroying it. And the card I'd just replaced. And the crap old card from my old computer- finally, down to my last junk video card- I discovered the REAL problem. Was time to get a new computer anyhow *sigh*
Posted By: gfretwell Re: Pool Heater - 01/23/08 05:46 PM
I can't seem to keep a fan in my wifes PC (3 bad ones so far) and it has over temped dozens of times with no apparent damage. It just locks up and shuts down the CPU. It took a while for me to figure out what was happening since she just unplugs it and plugs it back in at the first hint of any problem. That seems to kick the fan off again.
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