Separate pump, suctions and returns for heat pump?

[speedmeup]

My pool builder has suggested having an entirely seperate circuit for our heat pump. 20kL pool in Sydney Australia with a Remco cover that we want quite warm. What do people think of this? Anything to add to my list below? Anther option would be to have variable bypasses on a 'bus' type setup with just one pump but the ability to adjust how much water goes to the filter, chlorinator and heater or bypasses each.

pros
can run heating only without filter&chlorinator or vice versa
can suck water for heating from bottom of the pool instead of the skimmer where it's likely already warm

cons
water for heating wouldn't go via main filter so might dirt enter the heat pump
noisier when both pumps are running
extra suctions and returns = more possible points for water to leak from the pool

 

[ajw22]

What problems are you trying to solve by this setup?

I think any theoretical benefits will not be seen in day to day operation of the pool while it adds complexity to your equipment.

You need to have a filter in the circuit to protect the heat pump.

You get even heating in the pool by proper return design and placement. Not by sucking in water for the heater from the bottom. Floor returns are used by some builders to put heated water into the bottom of a deep pool for more even heating.

What will the depth profile of the pool be?

How will you be using the pool? As a swimmer you only care about the water temperature in the top 4 to 5 feet of the pool where you will be.

 

[SacPoolPros]

The heat pump should be plumbed off your filter pump so it should always have filtered water no need to have a separate suction and return for it.

 

[speedmeup]

What problems are you trying to solve by this setup?

I think any theoretical benefits will not be seen in day to day operation of the pool while it adds complexity to your equipment.

You need to have a filter in the circuit to protect the heat pump.

You get even heating in the pool by proper return design and placement. Not by sucking in water for the heater from the bottom. Floor returns are used by some builders to put heated water into the bottom of a deep pool for more even heating.

What will the depth profile of the pool be?

How will you be using the pool? As a swimmer you only care about the water temperature in the top 4 to 5 feet of the pool where you will be.

I think PB's view on heat pumps is informed by solar heating pools both having a low dT compared to gas heating so the aim is to allow heating to run for as long as possible even when filtration&sanitising is not running.

Pool depth will be 1.7m but average depth only about 1m. It will be a social/relaxation pool.

Thanks for your reply.

 

[ajw22]

With a maximum pool depth of 1.7m the idea that you need to heat the pool from the bottom makes no sense. Your pool is too shallow for it to make a difference.

Why don’t you want filtration & sanitation at all times the heater is running?

How will you be sanitizing the pool?

I run my VS pump 24/7 to always keep the water circulating, filtering, and the SWG generating chloirine.

 

[speedmeup]

With a maximum pool depth of 1.7m the idea that you need to heat the pool from the bottom makes no sense. Your pool is too shallow for it to make a difference.

Why don’t you want filtration & sanitation at all times the heater is running?

How will you be sanitizing the pool?

I run my VS pump 24/7 to always keep the water circulating, filtering, and the SWG generating chloirine.

I can imagine there will be times when the pool is perfectly clean and sanitised but not warm enough so I guess that's the only reason to run heating alone but I agree it seems to make more sense to just size everything right and put everything in series rather than try to cover all possibilities. Planning to use a salt water chlorinator.

 

[ajw22]

It does not cost you anything to be filtering and sanitizing anytime you are heating the pool.

There is no benefit to separating them, it only adds complexity and cost to your system,