teledyne laars spa heater barely heating

[kevincw01]

Teledyne laars model esc heater for in ground spa. Hot water exit in spa is luke warm at best an hr later but the heater appears to be running the whole time. I made a video and linked below. Sorry its upside down. I'd appreciate tips on what you think I should check to find the source of the problem.

https://www.youtube.com/watch?v=IM9zecv ... ata_player

 

[linen]

Welcome to tfp, kevincw01

A couple of questions:

1. Is the spa attached to a pool or is it isolated?
2. Is this a new problem?

 

[kevincw01]

Hi there. No, not connected to a pool. I just bought this house so I don't know if its a new problem. The previous owner did say she just had it serviced and should be hot within an hr.

 

[ps0303]

Well the video looks like you have a strong flame and it's burning good. Does it stay running constantly? How is the water flow in the spa? If you can take your hand and cover one of the inlets in the spa without the water pushing it out of the way, then your flow rate is very low.

 

[kevincw01]

The heater runs the whole time. The inlets are very strong. There is one inlet that I believe is the heater water exit aand its relatively low flow and Luke warm. The other jets are cold. I believe water is making it to the heater because I accidently bumped a valve that dumps water out of the system and the heater immediately kicked off.

 

[ps0303]

So you are telling me that only ONE inlet into the spa has warm water coming from it? Is this a pool/spa combo and you manually change valves to heat the spa or does the spa have it's own pump? How about a picture of the entire setup you have.

 

[kevincw01]

Spa only setup

 

[kevincw01]

Picture of setup attached as requested. Any ideas?

 

[ps0303]

So the outlet from the filter goes directly into the heater and then out of the heater goes direct to the spa? No other pipes going to the spa?

 

[kevincw01]

I see the point of your question but I don't know the answer. If there's only 1 jet that's warm and the other jets are cold then there must be 2 outputs from the equipment to the spa, correct? I will look again.

 

[ps0303]

I would say you are correct. I guess there is a possibility that the heater is only returning heated water thru one jet.

 

[kevincw01]

So I did check and there 3 pipes, 1 for blower, 1 for incoming water and 1 for outgoing water. So, no clue there which drove me to bite the bullet and spend the $85 for a service call which he ofcourse fixed in 5 minutes. Unfortunately I was not there to see it because I'm on business travel.

The following is me paraphrasing the info I got from my wife who heard it from the pool guy. Any clarification would be appreciated so I know how to fix it next time. There is a 240V transformer that steps the voltage down to 27V in the heater. The purpose of this circuit is for safety to prevent scalding. Somewhere in that transition, there's a fuse which can lose contact over time. That fuse is no longer sold so he bypassed it. Apparently, the scalding safety circuit is not really a concern in our system (not sure how that could be). I'm not sure how this was the solution since the burners were always on (and if they're on then I assume water must be passing through and where else is it going except to the spa).

 

[ps0303]

Hmm, I would think it was a temp sensor that stops the unit from over heating the water. My guess is the unit might have been cycling on and off only getting to a low temp and staying there. I would consider replacing the unit not too far down the road to a more reliable unit.

 

[poolguy15]

So I did check and there 3 pipes, 1 for blower, 1 for incoming water and 1 for outgoing water. So, no clue there which drove me to bite the bullet and spend the $85 for a service call which he ofcourse fixed in 5 minutes. Unfortunately I was not there to see it because I'm on business travel.

The following is me paraphrasing the info I got from my wife who heard it from the pool guy. Any clarification would be appreciated so I know how to fix it next time. There is a 240V transformer that steps the voltage down to 27V in the heater. The purpose of this circuit is for safety to prevent scalding. Somewhere in that transition, there's a fuse which can lose contact over time. That fuse is no longer sold so he bypassed it. Apparently, the scalding safety circuit is not really a concern in our system (not sure how that could be). I'm not sure how this was the solution since the burners were always on (and if they're on then I assume water must be passing through and where else is it going except to the spa).

Bad temp sensor, failing ignition control or excessive water flow through the heater. A temp rise should be done along with ohm'ing out the temp sensor.

There are 2 in-line fuses in the safety circuit - the 2A fuse that protects the transformer in the event of a short, and the fuseable link that will melt when the heater has rollout or excessive cabinet temperature. If the heater is turning on, the safety circuit is either being bypassed or everything is working correctly. The thermostat is wired from the pressure switch and then back to the IND terminal on the Fenwal. The heater firing means you're getting 24vac back to the ignition.

If the fuseable link was jumped, I highly recommend having a new one installed in the safety circuit. If the 2A fuse was jumped, the worst that can happen is a short blows out the transformer and it costs you way more to replace than the fuse would have.