Lines to pool heat exchanger

[goosegunner]

I am going to install a heat exchanger to heat our pool after cloudy spells in the summer. My equipment area is about 45' from my primary/secondary manifold set up.

I am going to bury the lines about 12 inches down in sandy soil. And will blow them out and cap in the winter.

Would it be better to bring pool water closer to manifold with 1-1/2" shcedule 40 or send the heated water to the pool equipment area?


What would be your recommendation for insulated lines be if I send the boiler water to the equipment area?


gg

 

[DaveBP]

Would it be better to bring pool water closer to manifold with 1-1/2” shcedule 40 or send the heated water to the pool equipment area?

If it were pool water flowing between the boiler and equipment it would be a lower temperature flow and therefore less heat loss to the environment than if it were the hotter boiler water flowing out there. That and the convenience of having the HX and related piping in the boiler area where you can monitor it while burning.

How would PEX deal with the higher chlorine concentration in typical pool water compared to city water?

 

[goosegunner]

How would PEX deal with the higher chlorine concentration in typical pool water compared to city water?

The pool water won't be in the pex unless you are suggesting using 1-1/2" pex to run the pool water to the boiler area?

Black poly irrigation pipe handles pool water so I believe 1 1/2" pex would.


Thinking about it some more, running the pool water to the manifold area would probably increase my pool working pressure. Not really a good thing. I would have to balance flow some how with valves.

gg

 

[DaveBP]

Well, black poly pipe would be a lot cheaper. You just need to make sure the circulator on the pool side is always running when the boiler water is running through the heat exchanger because the temperature of the boiler water could soften up that poly pipe near the HX very quickly if the heat were not being carried away to the pool.

 

[goosegunner]

Well, black poly pipe would be a lot cheaper. You just need to make sure the circulator on the pool side is always running when the boiler water is running through the heat exchanger because the temperature of the boiler water could soften up that poly pipe near the HX very quickly if the heat were not being carried away to the pool.

I was going to use one of the zones from my Taco panel to turn on the ciculator for boiler water. I will probably have pool water just running all the time. I will some type of switch to kill the 24 volt signal if I have to shut down pool pump.

gg

 

[nhdblfan]

I was in the swimming pool biz for 25 yrs (and pleased to be out of it !) and can't give any advice on the boiler part but I plumbed in 100's (maybe over a 1000) heaters.
First-the heater is always plumbed after the filter (pump to mulitport to filter to heater)
When we did them we used copper (no galv pipe as it does rusts with the corrosive pool water) heat sinks at the heat exchanger,say 3 ft on both input and out.
A check valve on the input,and a time delay-15 mins on the timeclock) to prevent the hot water from backing up to pool equipt when pump shutdown.
We then used a six inch shc 80 (grey PVC) heat sink into the female threads of the copper heat sink.
Then we used sch 40 pvc but you could run the poly (be sure to double clamp-opposing,and silicone at each fitting) to save funds and time.They make a greenleaf which is much stronger and will resist puncture.You migh also lookinto flexible PVC,come in a roll like the ploy,easy to plumb but a bit more $$.

With 90ft more pipe your pump may need to be upgraded if it was marginal before,if its a straight level run you should be ok.

HTH

 

[goosegunner]

I was in the swimming pool biz for 25 yrs (and pleased to be out of it !) and can't give any advice on the boiler part but I plumbed in 100's (maybe over a 1000) heaters.
First-the heater is always plumbed after the filter (pump to mulitport to filter to heater)
When we did them we used copper (no galv pipe as it does rusts with the corrosive pool water) heat sinks at the heat exchanger,say 3 ft on both input and out.
A check valve on the input,and a time delay-15 mins on the timeclock) to prevent the hot water from backing up to pool equipt when pump shutdown.
We then used a six inch shc 80 (grey PVC) heat sink into the female threads of the copper heat sink.
Then we used sch 40 pvc but you could run the poly (be sure to double clamp-opposing,and silicone at each fitting) to save funds and time.They make a greenleaf which is much stronger and will resist puncture.You migh also lookinto flexible PVC,come in a roll like the ploy,easy to plumb but a bit more $$.

With 90ft more pipe your pump may need to be upgraded if it was marginal before,if its a straight level run you should be ok.

HTH

Thanks,

I am thinking of just running some cheaper wrapped pex to the pool area and using a tube and schell right there.
I am hoping to using balancing valves so I don't have to change the route of all the water to the heat excanger.

If that doesn't work I also have a dedicated solar return. It is T'd in after the filter. I open a valve and some water just naturally takes that route (actually reduces back pressure some). It dumps back into the pool on the opposite side of the pool of my normal returns.

I will look into using copper/ schedule 80 to make the connections. One thing I don't like with copper is It causes green hair on blondes.



gg

 

[nhdblfan]

Hi goosegunner,
that mixing valve is probably a good idea,it will however slow the heating.You want the heat to go to the lowest return,furthest from the skimmer ('s).Ideally the pool should be heated from floor returns (as you heat a pot of water) but they only have them in the floor cleaning systems.

The "blond reaction" is not from the copper,its the water !The heat exchangers in all the pool heaters are made of copper,its does break down if the PH is low or the combined chlorine is to high.Check your Ph (should be 7.4-7.6) Total Alkalinity ( should be over 130) and free chlorine (1.0-1.5)

if that exchanger is up hill or even level with the equipment don't forget the check valve-brass one.

happy to help

 

[DaveBP]

The “blond reaction” is not from the copper,its the water !

A friend of mine was working at a swanky hotel in Newport, RI back when we were young. One of his duties was pool maintenance. Crack of dawn one morning it was scheduled super-chlorination time. He measured out the normal dose and dumped in in the end of the pool where he always did. SOP.

Minutes later, one of the guests walks out of his room and jumps in. Yeah, right into the cloud of chlorine. His blond hair did turn green. Not a 911 situation except that he was part of the movie cast that was in town filming. If it had been a horror movie it might have been OK. But it was Robert Redford in town to film The Great Gatsby. The production manager wanted my friend's head. They lost most of the morning's shooting.

 

[nhdblfan]

That's not uncommon,most public pools have lots of chloramines or combinded chlorine.You have to shock the water-bring it up to over 10 parts per million to break them and then you can get the "free chlorine" level of 1.0 to 1.5;

http://www.custompools.com/?page=trouble_water
"High Levels Of Chloramines ;
Chloramines, when in high enough levels can cause skin, hair and nails to become discolored. The most susceptible are light-skinned, blond haired (natural or dyed) persons. Again, to destroy the chloramines, shock with 1 lb of Breakout per 10,000 gallons or follow your chlorine manufacturer’s instructions for super-chlorination."

It can also be a case of the PH being to low,it strips copper out of the heat exchangers (and can also destroy pool liner ) and turns blond hair green.Yo have to be careful to check both the PH and the Total Alkalinty to be sure they are not to low.The rain is very acidic and brings the PH down.
One other thing to watch is the cheaper algicides with copper in them.That reacts with the chlorine and clings to the blond hair.Buy the "quat" non copper algicide ,its cost more but works better and is safer then pouring copper in your pool.

 

[goosegunner]

Thanks for the tips I will review them as I plan my plumbing.

I use the poly quat algaecides only, no cheap stuff with copper. All plastic pipes no heater yet except solar. I do watch ph and use the grocery store method of chemicals. Chlorine, borax for ph up, muratic aicd ph down, and poly quat.

gg

 

[nhdblfan]

Thats good, your on the quat or even better the poly. Be sure to check the T/A (should be over 120)as it effects the PH.You raise it with baking soda-sodium bicarbonate.Try and use the best chlorine trichlor (99%),cost more but it ends up cheaper if you use stablizer and keep the water balanced.

You can get those heat sinks is stainless as well BTW if you want to avoid copper (I bet its in the heat exchanger thou),they are more expensive thou.

http://www.poolpartsonline.com/p-530-stainless-steel-heater-connectors-heat-sinks.aspx

happy to help