Heat Exchanger/Boiler Sizing

Chado613

New member
Apr 30, 2018
2
Ontario
I am trying to improve the water temperature in my pool. The pool is a 22 000 gallon inground indoor pool and the water is always cold. Middle of summer the water may not reach 70 deg f.(Live in Ontario Canada)

This pool is not used in the winter as the current heating/de humidifcaiton system for the room does not work(Dectron). The previous owner never had it working either. I am only interested in heating the pool in the summer months.
The current heating system for the pool and the house is having the pool water piped into and oil boiler (164k btu) and then piped in series into indoor wood boiler(BTU unknown however would be less than oil boiler). Both of these boilers are probably from the late 60s or early 70s and I will be looking to replace the oil boiler with likely propane as my oil tanks are expired. The wood boiler has the pool pipe reduced down to 3/4" so I feel this reduces the flow too much. These do not do a sufficient job for heating the pool and is making the pool useless as its too cold.

I would like to add a new heat exhanger and size the new boiler to heat the pool. Several websites have different methods for sizing heat exchangers/boilers( So far I have calculated 185 000 - 367 000 btu).

Does anyone have experience that they could share?
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
16,225
Northern NJ
1 BTU will raise 1 lb of water 1 degree. Your 22,000 gallon pool is 180,000 lbs of water. Your 164K BTU hearer will add less then 1 degree an hour to the pool. And depending on the insulation of your pool room you can lose that much heat from your pool.

There is much more that needs to be known about your pool to determine how best to heat it. But basically you need many more BTUs.
 

Chado613

New member
Apr 30, 2018
2
Ontario
Thanks for the reply ajw22. I realize I need more BTUs, I am trying to gather advice to appropriately size the heat exchanger.
Based on what you posted, it looks like i will need at least 182 000 btu heat exchanger. Keep in mind I plan on upgrading the boiler as well.
 

wogster

In The Industry
Apr 30, 2018
148
Toronto, Ontario, Canada
I am trying to improve the water temperature in my pool. The pool is a 22 000 gallon inground indoor pool and the water is always cold. Middle of summer the water may not reach 70 deg f.(Live in Ontario Canada)

This pool is not used in the winter as the current heating/de humidifcaiton system for the room does not work(Dectron). The previous owner never had it working either. I am only interested in heating the pool in the summer months.
The current heating system for the pool and the house is having the pool water piped into and oil boiler (164k btu) and then piped in series into indoor wood boiler(BTU unknown however would be less than oil boiler). Both of these boilers are probably from the late 60s or early 70s and I will be looking to replace the oil boiler with likely propane as my oil tanks are expired. The wood boiler has the pool pipe reduced down to 3/4" so I feel this reduces the flow too much. These do not do a sufficient job for heating the pool and is making the pool useless as its too cold.

I would like to add a new heat exhanger and size the new boiler to heat the pool. Several websites have different methods for sizing heat exchangers/boilers( So far I have calculated 185 000 - 367 000 btu).

Does anyone have experience that they could share?
Sounds like this is not plumbed correctly, there should be a heating loop, that goes through the wood boiler, then you have an aquastat that if the water is below a set point, fires the oil boiler, this then goes through a heat exchanger, pool water goes through the other side of the heat exchanger, so boiler water and pool water never touch, boilers can contain toxic materials like lead, you don't want in pool water. Bonus here, you can feed that same boiler water through an air handler to heat the room in winter months, a heat recovery ventilator mounted to the air handler, can handle the winter humidity.