Question about Jandy Laars Lite2 Ld 400,000 Btu Heater

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Can you bypass the heater so pool can prime

The heater water system is leaking and doesn't allow the pool to prime. I was looking for a way to bypass the heater and isolate it from the pool.

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The pool return pipes are connected to the heater with pipe unions. You could get a set of unions to match them and make a "U" shaped pipe section to bypass the heater. using a couple of 90's and the unions .

Posted on Jun 01, 2010


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Water is not going from pump to water heater

check to see pump is primed and pumping, could have broken impeller or plugged with trash, use a makeup mirror and a flashlight to look in the hair basket water entrance to the pumps impeller fore damage or debris.. always prime the pump with a fw gallons of water after any repair or service.
Jay the pool pump repair guy longwood florida.

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1 Answer

Leaking pool pump

It is difficult to see exactly where the leak originates. Obviously the drips are coming from the front of the pump, but the leak may be elsewhere. I would suspect that the origin may be at the seal, because a breech in front of the seal would not allow the pump to catch prime.
This normally indicates that the pump has run for some amount of time with no water flowing through it. However it also is not clear if the pump is running or not.
In the case of an above ground pool, water may leak at any point that there may be a breech at any point, being that the pump is below water level.
Look very closely at the drip and try to follow it upstream to see if you can determine where the water is originating. Hard to troubleshoot based on available info.

Jul 01, 2013 | Pool & Spa

1 Answer

My Teledyne Laars LLD spa heaters starts and heats for a couple of minutes thins shuts down. I have tried this several times with the same results. I hear the switch click and then the heater ignites and...

Since the heater fires it sounds like it could be the bypass valve stuck open. The bypass valve allows some of the water to enter the heater, while the rest bypasses the heater and returns to the pool.

If the bypass is stuck open, or broken, it allows the vast majority of the water to bypass the heater and continue to the pool. The water that is in the heat exchanger will become too hot due to slow flow and activate the high limit switch, turning the heater off.

The bypass is located where the pipes attach to the heater and can be checked or replaced if needed fairly easily.

Apr 16, 2013 | Pool & Spa

1 Answer

I came back from vacation to find the pool not running. Power must have triped while gone. Turned power back on at the breaker. Went to the autopilot to turn system on. Autopilot was fine and had power but...

It sounds like your pool pump might have lost its prime. Make sure the lid is on and is secured tightly. Check your water level to make sure that it is above the skimmers. Make sure the suction lines, pump strainer, and pump pot are full of water. After you check these things, re-prime. If this still doesn't solve the problem, also check for clogged baskets and worn out gasket/valve. Make sure that you don't have an visible air leaking in the pool (look for bubbles).

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1 Answer

Banging sound after burner is turned on for about 30 seconds

Thank you for posting your question! experts do our best to answer your questions as thoroughly as possible, but we may not always have 100% of the information that we need to make a thorough "diagnosis opinion". Please take that into consideration prior to rating our answer on how it helped you with your situation!

If you have an external by-pass it needs to be closed. An external bypass is simply a valve (or two) that direct the flow away from the heater. This valve is usually between the pipes on the in and out of the heater. When you close it (closing the bypass), water is forced through the heater. When it is open (open the bypass) no water goes through the heater, or if you leave the valve partially open, then only "some water" goes through the heater. So if you open the bypass (directing water away from the heater) or only have it open part way, the water in the heater boils and turns to steam. With no where to go it starts banging and knocking.

If you close this valve,or it is already closed, and you still have trouble, then we can identify that the internal by-pass has gone bad. The overheating from the improper placement of the valves may cause additional damage to the internal bypass.

Some additional questions to consider:

Q: Does the banging continue until the heater eventually shuts off or does it quit shortly after the heater burners start up? I
POSS. DIAGNOSIS: n either case you can repair the heater for much, much less than a new unit. The bypass may be the issue if it is stuck closed or has been damaged as noted above.

Q: What is the pressure on the filter?
POSS DIAGNOSIS: It is also possible there is an issue with the pump and/or filter not allowing enough flow thru the heater. Poor flow may be caused by a clogged or damaged impeller, suction leaks allowing too much air into the system, or the filter needing service and not allowing enough water to pass through to the heater.

In all cases, I suggest inspecting all components of the system, servicing the filter with a back wash, filter clean and DE recharge (depending on applicability of your situation).

It seems like a lot, but most of the time, the issue is a very simple....there are just a lot of components to simple answers!

--The Ugly Pool Guy

Dec 11, 2010 | Hayward H Series Pool & Spa Heater 400k...

1 Answer

My pool pump will run fine once I prime the system from the top of the pump basket. Then once the timer shuts the pump off, when it trips the switch to run again there is no water in the pump and it cannot...

If you are a long way above the surface of the pool and you have a leak on the filter it could be a check valve problem.
With it competly loosing the prime it sounds more like a suction leak. This will be in the plumbing and will need a re-plumb or it could be as simple as a lid "O" ring or cracked lid.
What happens is the air get's in the tank and air will compress when under pressure. Then when the pump shut's down the air can expand again. When it does it will rush back through the system and blow the prime right out of the pump. Quite often you will see water blow out of the skimmer or just blow the skimmer lid off. I hope this helps. Good luck.

Sep 09, 2010 | Tristar Hayward 15 Hp Inground Swimming...

1 Answer

I have a raypak heater when i fire it up the water temp go's up real fast

I assume this is on a swimming pool. It might depend on how it is plumbed in. Quite often, there is a bypass valve allowing the pool water to bypass the heater incase it's being serviced, or a leak etc. You would close inlet and outlet valves to heater and open the bypass. This would isolate the heater. If you have the bypass open while heating, you will reduce (or eliminate) the flow through the heater. This will allow the water in the heater to heat very fast, and lets be glad there's a temp control or your plumbing would melt. These heaters should have full flow through the heater, and you'll see min temp rise per pass.

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1 Answer

My Jet Pump Looses it's prime at night.

I assume the pump is not running at night. If the pump is higher than the pool, and the inlet and outlet to the pool are both under water, then you have a small leak. This could be allowing the water to leak out of the line. Or, if the leak is higher than the pool surface it is allowing air to leak into the line, which allows the prime to run down into the pool. If you found this useful, please vote. Thanks.

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Circulating pump shutdown piolet lite shut off on boiler

It sounds like you have a circulation problem. The bleed off valve should only open when you have a presure problem (nonexistent on the open system of a pool) or when you have a over herating problem witch will shut down your pilot also. Check your heater by-pass valve. (A valve in an "H" on the inlet and outlet of the heater) This should be 80-90% closed to force water through the heater. If not this the standered; check the baskets, clean the filter and make suree there is enough water to keep the pump primed. I hope this helps, if not send more info on what is going on.Good luck.

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