Hayward Pool Heater has flame coming out of the top vent!

[joelq]

Hi all -

Just getting the pool in shape for the swimming season and decided to fire up the heater. It is a Hayward H400 Natural Gas heater, going on 4 years old. The heater is controlled by an Aqualogic PS-8. The heater appears to fire up just fine (blower motor comes on first, followed by ignition several seconds later), but I noticed a couple things:

1 - after several seconds (maybe 30-60 seconds?), I will start to hear whining sounds - almost sounds like a baby whale looking for its mom. To me, seems like pressure that's building as the water comes up in temp, but isn't getting relieved somehow. I took out the bypass valve and made sure it was moving freely (it was), and checked the thermal control valve in a pot of boiling water and it was operating properly. After this, it seems the whining sounds have lessened, but are there other spots to check? Should these parts just be replaced?

2 - every so often (maybe every 2-3 minutes), flame will come out of the vent on the top of the unit! About 3-5 seconds later, it will "catch" itself and go back to operating normally. Only to happen again another 2-3 minutes later. Any ideas on what to check for this one?

Thanks everyone!

 

[Lershac]

break out the weenies and marshmallows!

Really, shut it down and get it serviced!

 

[PoolGuyNJ]

Flames out the vent are not good and are dangerous. It sounds like it's has a sooted up heat exchanger and/or burners. You need to remove the covers and look at the heat exchanger and burner tubes and burner orifices.

Are you sure you have enough of a gas supply?

Scott

 

[joelq]

@lershac - good idea! ;-)

@scott - I have no reason to believe I don't have enough gas supply, but I guess I really don't know. How can I tell that? As far as the sooting, can you explain how that could cause the flame to shoot out of the top?

Thanks everyone!

 

[PoolGuyNJ]

Insufficient air not burning all the gas or an intermittantly clogged orifice can cause sooting as can unsufficient air. If the heat exchanger's fins are clogged, you won't get a good up draft that will pull in fresh air from below.

WRT the gas supply, if you are using natural gas, the gas meter will only allow so much. It will say how much it's rated for on it's label. It needs to supply enough for the house to use in addition to the heater. If it's a borderline or under rated, and the hot water heater, stove, oven and dryer are on, you may be starving the heater.

Scott

 

[joelq]

Insufficient air not burning all the gas or an intermittantly clogged orifice can cause sooting as can unsufficient air. If the heat exchanger's fins are clogged, you won't get a good up draft that will pull in fresh air from below.

WRT the gas supply, if you are using natural gas, the gas meter will only allow so much. It will say how much it's rated for on it's label. It needs to supply enough for the house to use in addition to the heater. If it's a borderline or under rated, and the hot water heater, stove, oven and dryer are on, you may be starving the heater.

Scott

Thanks, for the explanation, Scott!

By the way, is there a maintenance manual somewhere that shows the screws that need to be undone to get the top off? I didn't see any diagrams showing the screws in the manual the installer left with me.