Adding a Heater bypass to my new inground pool installation.

[frankos]

After several years of a little 3000 gallon inflatable ring pool in my backyard, we finally jumped in for the proper in-ground pool last September. Constructed is finally nearing completion. There's additional construction going on on site or would have probably been done by now. The equipment has been set and plumbed a long time ago, and really the only thing left for the pool is the deck and plaster. I hadn't put much thought into the plumbing until recently.

The other day I was thinking that since I have a salt system and won't be using my heater a whole lot, that it might make sense to put a bypass on it. So I got to looking around and sure enough lots of people recommend instant the bypass. Seems the only reason not to is cost. Aaa Another thing I noticed is a lot of people put a check valve between the salt cell and the heater.

So when I went out to look at the system to see how difficult it was going to be to install a bypass, I noticed I did not have a check valve either. It seems installing a check valve and moving the salt cell and adding bypass is pretty straightforward. but just the fact that there was this much wrong has me wondering what else is wrong?

So here are some photos of my installation. I'm asking for help to identify any major problems that I definitely should request them to fix, as well as minor issues that could be better if done differently.

Thanks so much on advance.

 

[mknauss]

Welcome to the forum!
There is no need for a check valve between a SWCG and the heater. That is a carryover from using Trichlor. Trichlor is acidic and damages heaters.
See Heater Bypass - Further Reading
I suggest you read ABC's of Pool Water Chemistry.

 

[frankos]

Thanks Marty... Okay, so I check valve? Several people online suggest that Chlorine is bad for some parts inside the natural gas heater. But the aformentioned ABCs of pool chemestry dont mention this. It does mention low PH being bad for the heaters. So, do I even need a bypass ? I honestly figure I'll use the heater in March/April to get the pool up to temp and help hold it there and maybe in sept/oct to extend the season. The other 8 months of the year there is no point. It seems to me taking it out of the circuit would help the pump run more efficiently whilst relieving any unnecessary wear from use on the heater....???

 

[mknauss]

My pool water goes through my heater 365 days a year. You do not have a Signature completed so I do not know what equipment you have but most pool heaters have an internal bypass. Thus most of the water bypasses the heat exchanger until the water temperature reaches ~120F.
You might see a small reduction in filter pressure if you bypass the heater with plumbing.

 

[frankos]

Thanks Marty, just reading another thread and I found a post where you had recommended reading this page. I left there feeling like it was a good idea. But then I kept surfing as there are a ton of good posts about heaters and bypasses here. I read this post and it seems that most modern equipment is fine without a bypass. So, I'm somewhat confused. I see I'm likely fine without out it, however it couldn't hurt to have in the future. I will

So, moving forward, where do I plumb in my sacrificial anode? Before or after the heater?

Oh and I'll add the equipment to my signature soon.

 

[mknauss]

A heater bypass is fine to have if you have the room to install it. It allows you to have an issue with the heater and not have to intervene with your piping to keep operating the pool. In your area, you might consider it because it gets cold. A bypass would allow you to properly drain and blow out your heater in the winter, if you do not fully close your pool.

 

[mknauss]

Sacrificial anodes serve no purpose in a pool. What metal are you trying to protect?

 

[MikeCosta]

Water heaters with internal bypass are typically rated up to 40 gpm. If you have requirements for running higher flows (features, spa jets, floor cleaners, etc); it can be efficient to install a diverter valve to allow some of the flow to not be restricted by the heater. This is basically a partial bypass setup and often used alongside larger pipes (2-1/2”+). Same would go for the SWG. It really depends.

 

[frankos]

Okay details of my pool are posted in my sig now. I like the idea of draining the heater, not just in the winter, but the summer too. But on the flip side I don't' want to cause mineral buildup on my heater elements... Maybe a bypass left open partially to allow more efficient flow as MikeCosta suggests would be best?

As for the sacrificial anode, it's to protect the metal inside the heater.

 

[frankos]

So I'm confident I want to add a bypass. My plan is to put a 3 way between the filtter and heater, then a check after the heater. The bypass circut would connect in after the check valve.

My new question is, on a 3 way, it seems that in most applications, the trunk is the input and the output points are the two arms. For my use it would be best if I connect left arm of the T as the input and the output be either the right arm or the trunk (downward direction) or both if I choose to mix? I cannot see any reason why this wouldn't work but I don't want to break anything either.

 

[ajw22]

My new question is, on a 3 way, it seems that in most applications, the trunk is the input and the output points are the two arms. For my use it would be best if I connect left arm of the T as the input and the output be either the right arm or the trunk (downward direction) or both if I choose to mix? I cannot see any reason why this wouldn't work but I don't want to break anything either.

Water flow direction does not matter on a 3 way valve. Water makes 90 degree turns fine. You can reset the INPUT tag on the valve to correspond with which port the water goes into.

 

[frankos]

I wanted to update my progress. The fill started yesterday. I plumbed in the bypass and I really like what I came up with. Here are a couple photos.