Hayward Heater Rumbles & Vibrates Like a Harley.

[quikcolin]

Here’s the story.

Brand new pool, heater and all components. Hayward 150,000btu heater is causing me grief since the venting was installed. I hired a gas fitter to install the gas system middle of the summer last year. He hooked up the gas, but couldn’t install the venting (it’s located inside a pool house) as he had to order the stainless duct. (backordered). So for a week or two I ran the heater without the venting (with doors to pool house open) and it ran flawlessly. Then the gas fitter came back and installed the Hayward brand heat shield thingy that mounts to the top of the heater and the duct work. He has the duct work going straight up for 4’ and then a curved piece runs it out the back of the pool house. From the moment he installed the venting it now shakes and rumbles like a motorcycle. Not all the time, but for about 60% of the time. It’s so violent sometimes I turn it off in fear of causing damage.

I spoke to Hayward today (they have the best customer service period) and after sending them photos of the install and my story they feel that it’s not the install, but rather the heat exchanger. They feel there is likely a calcium build up that needs to be cleaned. I’m not so sure? That quickly? It’s less than a year old. It started acting up after about a month of use.

I am having a hard time with the fact that it’s almost brand new. It ran perfectly and that it only started to act up after the venting was installed. It can’t be a coincidence?

Here are some photos of my setup. Any insight or suggestions are appreciated.

 

[ajw22]

To understand if it could be calcium buildup we need to know your water chemistry. We rely on owner testing and I know that you can't get the test kits in Canada that we use - the TF-100 Test Kits or the Taylor K-2006C. If you get other items from across the border maybe you can arrange to get one.

If you can tell us your

FC
pH
TA
CH
CYA
Salt
Water Temperature

What we are looking to calculate is your CSI using PoolMath

You might want to review ABCs of Pool Water Chemistry and Calcium Saturation Index (CSI) - Trouble Free Pool

As far as installation issues goes maybe @kadavis @ps0303 has some thoughts.

 

[kadavis]

What model is this, and type of gas

 

[jimmythegreek]

It's probably coincidence with the timing. Can you post the specs of heater and if gas or propane. If the unit wasnt venting properly it would shutdown to overheat sensor. I beleive the haywards have internal bypass and when they chatter they can vibrate and make noise. When you say it acts like a Harley is it actually shaking the whole unit or just humming? How do you maintain your water sanitization?

 

[quikcolin]

Thanks guys! It's a Hayward 150,000 BTU Gas Heater. From haywards input, it appears to have been connected correctly - they seem to be satisfied with the venting connection. Just seems like a heck of a coincidence - is it even possible for calcium to build up in such a short amount of time (even with the worst water conditions - I take my water into my local pool store weekly and adjust accordingly). I'm hoping it's just as simple as stated... interesting about the internal bypass that "jimmythegreek" mentioned.

To answer the question about the shaking and vibrating, it seems to be the whole unit, the noise is more violent than the physical shake. My system is Hayward everything. VS pump, into a cartridge filter, into the heater, through a salt cell and back into the pool.

 

[Razorhog]

My brother had the same thing happen, it was a bypass valve that was open. The noise is water turning to steam due to insufficient flow. I believe he has an external bypass valve, and it was as simple as closing it to fix the problem.

 

[quikcolin]

My brother had the same thing happen, it was a bypass valve that was open. The noise is water turning to steam due to insufficient flow. I believe he has an external bypass valve, and it was as simple as closing it to fix the problem.

This is interesting! I literally don’t know anything about this stuff. Where would this bypass valve be located?

 

[ajw22]

This is interesting! I literally don’t know anything about this stuff. Where would this bypass valve be located?

That is where the pipes connect the the heater.

 

[quikcolin]

That is where the pipes connect the the heater.

So it’s in the PVC plumbing that is installed into the heater, not on the heater itself? I don’t have a shut off/bypass valve installed on my plumbing near my heater.

Or is it something that Hayward has built into the heater somewhere?

Sorry for the silly questions, I literally know nothing about this.

 

[ajw22]

The heat exchanger is the first piping inside the heater wall. Look at where the white PVC connects to the black intake/outlet on the heater. That black block is what is shown in the drawing you posted.

I circled in red the cartridge retaining nut.

 

[quikcolin]

The heat exchanger is the first piping inside the heater wall. Look at where the white PVC connects to the black intake/outlet on the heater. That black block is what is shown in the drawing you posted.

Gotcha. And the bypass is inside that somewhere? I’m assuming it needs to be dismantled in order to access if it? Or is it as simple as a switch on the exterior of that black intake/outlet? Thanks again!

 

[ajw22]

See my edit above with the pic. Access looks like it is on the side.

 

[quikcolin]

See my edit above with the pic. Access looks like it is on the side.

Thanks for that. So does turning that end cap open and close the bypass?

 

[Razorhog]

Sorry I don't know the details, I wasn't there when they solved the problem and they live 1.5 hours away. I was trying to help them get their pool going when they bought the house and the heater would rumble. I have no clue about heaters either so later that week they called the pool store and they fixed it by closing (or opening) some valve. I got the impression it was a valve in the plumbing outside of the heater, not inside but I'm not sure.

 

[jimmythegreek]

Take a pic of the heater and its piping and post it. You say you have a VS pump which one? And what speed are you running the pump while heating? I ask because you need good flow when heating try around 2000 rpm or better and see if it stops. Keep going faster til you hit 3000rpm or it stops. If it doesn't stop the internal bypass is damaged. And while were on the water quality PLEASE order a test kit like the tftestkit and dont take your water to the pool store. They do not test water properly your levels are likely out of whack and you will end up with problems sooner than later

 

[ajw22]

Thanks for that. So does turning that end cap open and close the bypass?

I believe bypass is automatic based on water flow. Removal procedure is on page 49 of https://images.inyopools.com/cloud/documents/universalh-serieslownox.pdf

I don’t believe this is your problem. But may be worth taking a look at if easy to access.

 

[ajw22]

Sorry I don't know the details, I wasn't there when they solved the problem and they live 1.5 hours away. I was trying to help them get their pool going when they bought the house and the heater would rumble. I have no clue about heaters either so later that week they called the pool store and they fixed it by closing (or opening) some valve. I got the impression it was a valve in the plumbing outside of the heater, not inside but I'm not sure.

There is often an external water bypass valve installed to control the water flow rate through the heater. Heaters have a maximum flow rate that if exceeded will prematurely wear the heat exchanger. So the external bypass valve is used to adjust how much water goes into the heater and how much goes around it.

The banging and shaking of a heater is typically a lack of water flow allowing water to boil and steam needing to vent. Water should not be boiling in a heater.

Jimmy is on the right track of increasing water flow on the VS pump.

 

[quikcolin]

Thanks so much for everyone’s input. I’ve been running my Hayward VS pump at 2475 rpm during the day and at 8pm I have it slow down to 2200rpm over night. So I’ve always heated at 2475rpm. I have never heated over night (at the lower rpm). I’m going to turn the pump up to 3000rpm and turn on the heater (first fire up of the season) and see how she runs.

Stay tuned. Again, thank you everyone for all your help thus far!

EDIT UPDATE

Just ran the heater. I turned the pump up to 3200 rpm and it was shaking and thumping like a freight train. The venting was hot, but the water coming out of the jets was barely warmer than the pool water ( this is something I noticed last year as well. I was always surprised that the water coming out of the Jets when the heater was running was only a little warmer than the pool water… ). Water temp is 56 degrees (had heater set to 90). I have turned it off as it seemed even thumpier (is that a word?) then last year... but I was running it around 700rpm higher than ever before.

Is Hayward right? Is it the heater exchanger clogged up?.. how can that happen in a matter of months?

 

[jimmythegreek]

It could happen with bad water. I also wonder if theres something else going on. Try running it at 1800ish and see what happens. You could also experiment to rule out your original thoughts and take off vent stack and see what happens. Usually just simple selftapping sheet metal screws. A knowledgeable plumber would have it diagnosed quickly by opening up the intake and scoping the exchanger inside and outside. Not sure how handy you are there are videos I'd bet on youtube

 

[quikcolin]

It could happen with bad water. I also wonder if theres something else going on. Try running it at 1800ish and see what happens. You could also experiment to rule out your original thoughts and take off vent stack and see what happens. Usually just simple selftapping sheet metal screws. A knowledgeable plumber would have it diagnosed quickly by opening up the intake and scoping the exchanger inside and outside. Not sure how handy you are there are videos I'd bet on youtube

That’s a good idea. I’ll try a lower rpm... but I fear the heater will throw an LO code. Too little water flow. I’m fairly handy, I’ve looked all over for a step by step video without any luck