LO code on Hayward 300 heater

[OntarioCanada]

My heater is interlocked with the pro logic controller (one of the 2 wires going from the water pressure switch to the pro logic board).

I am very new to pools (just moved into house with pool first time) and trying to learn the basics so my apologies if I am not doing something right.

I have two issues:
1) I don’t know if I am doing something wrong when backwashing filter or if happens on its own (I turn pump off an stat backwash, I don’t turn heater off), I noticed the heater goes into manual control too often, I have to press the heater button on the pro logic pad to get it controlled by the pro logic system.

2) when the heather is not on, it sometimes shows the temp but most of the times show LO code. If I increase the set temp from the prologic setting to get it to start, the heater does come on then the LO code disappears. Is that normal or something wrong with the pressure switch that doesn’t detect enough flow when I’m the heater is not on?

 

[ajw22]

1) I don’t know if I am doing something wrong when backwashing filter or if happens on its own (I turn pump off an stat backwash, I don’t turn heater off), I noticed the heater goes into manual control too often, I have to press the heater button on the pro logic pad to get it controlled by the pro logic system.

You should turn the heater off a few minutes before you manually turn off the pump to allow the heater to cool down.

The heater should be off while you are cycling the pump during backwashing. You don't want the heater to try and fire up as your turning the water flow off and on.

Then enable the heater when you are done backwashing.

2) when the heather is not on, it sometimes shows the temp but most of the times show LO code. If I increase the set temp from the prologic setting to get it to start, the heater does come on then the LO code disappears. Is that normal or something wrong with the pressure switch that doesn’t detect enough flow when I’m the heater is not on?

Do you have a variable speed pump?

It sounds like everything is running normally.

When the heater is OFF your pump may be off or at a low speed and there is not enough flow for the Water Pressure Switch in the heater so you get the LO code.

When you turn the heater on the Prologic system increases the pump speed and the LO code goes away when there is adequate flow from the pump.

Don't worry about the temperature readings or codes on the heater display panel when the pump or heater is OFF.

 

[OntarioCanada]

thank

You should turn the heater off a few minutes before you manually turn off the pump to allow the heater to cool down.

The heater should be off while you are cycling the pump during backwashing. You don't want the heater to try and fire up as your turning the water flow off and on.

Then enable the heater when you are done backwashing.



Do you have a variable speed pump?

It sounds like everything is running normally.

When the heater is OFF your pump may be off or at a low speed and there is not enough flow for the Water Pressure Switch in the heater so you get the LO code.

When you turn the heater on the Prologic system increases the pump speed and the LO code goes away when there is adequate flow from the pump.

Don't worry about the temperature readings or codes on the heater display panel when the pump or heater is OFF.

I will turn heater breaker off before turning pump off for backwashing and will turn it back on after done with the filter and after turning the pump on, I have not been doing that.

Regarding the pump, it's single speed and the pump is always on. everything works but when the heater is not in use (pool water reaches set temp in the pro logic settings then it shows LO on the little display when it's sitting idle)

thank you for the reply

 

[ajw22]

You should not use a breaker as a switch.

Turn the heater OFF in your Prologic control or turn the heat set point below the water temperature so the heater will not run.