[davephan]

We don't use the heater at all for the pool, only for the spa. Without heating, the pool water temperature is as cold as 62 in the winter and 91 in the summer. We hear the spa only when we use it. It takes 15 to 40 minutes to heat up the spa in the summer to winter. But we don't use the spa in the winter when the air temperature is below the mid 70's. It would be a hassle to cover up the pool, and it would make the pool look ugly.

Another question to ask is what kind of pool heater do you have. The best heater for a spa is a natural gas pool heater. It heats fast, but costs much more to heat with than a electric heat pump pool heater. But you only use the spa heater when you're using the spa.

If we wanted to heat the pool, we'd buy an electric heat pump pool heater just for the pool. The heat pump pool heater is much cheaper to operate than the natural gas pool heater, but heats at about half the speed rate compared to the natural gas pool heater.

The rough estimate for heating a pool with a natural gas pool heater is $500 to $1,000 a month during the coldest winter months. The cost to heat the pool with an electric heat pump during the coldest winter months is about $150 to $200 a month.

So, if we were determined to use the pool during the winter months, we would buy an electric heat pump pool heater, just for the pool, and use the natural gas spa heater, just for the spa. If we bought the electric heat pump pool heater, we would pay another $1,000 for the electric heat pump pool heater that has a chiller option, to cool down the pool, during the hottest summer months.

So, if you're using a natural gas pool heater now, to heat the pool, then you're better off spending that money on an electric heat pump pool heater that has a chiller option than the pool cover, if you need to use the pool in the winter months.