Spa Blower shuts down

[bhunjp]

Ever since I bought the house about 10 yers ago the blower would shut off after some period of time (10 minutes to 1/2 hour). I never tried to fix it until now. The old blower fried so I got a new one - same make and size (240v,2hp). I thought the shut off issue would go away. It didn't.

When the pool pump only is on (fairly low flow to the jets) the blower seems to work without shutting itself off. All jets have bubbles. There are also bubbles on all jets when the pool pump is off and blower on.
Here's the problem. When the spa pump is on only the middle three jets have bubbles and the blower shuts off after a few minutes. All the jets have water flow.

Here is my set up:

pool spa with spillover to pool. The spa has it's own pump for the jet action or when the spa pump is off the pool pump provides spillover water. I also have a Silencer blower (http://www.hottubwarehouse.com/Silencer ... 20220f.htm). The spa has 5 jets that I think are Hayward jet air. They look like this: http://www.spaandpoolsource.com/sp-1434 ... lojet.aspx

Any ideas? Is my blower too large? Could my jets be clogged somehow?

Thanks,
B

 

[carolina pool]

Most residential blowers have an auto shut off mechanisn to keep them from overheating. The motors aren't really designed for continuous use.

 

[bhunjp]

Thanks for the reply. The autoshutoff is definitely kicking in. The bubbles last about 3 minutes until it shuts off. I then have to reset the breaker and wait about a 1/2 hour or more.

 

[carolina pool]

If the blower shuts off after 3 minutes and the breaker trips you have another problem.

Base upon your description, it sounds like the booster pump is forcing water into the air line backpressuring the blower.

I am not familiar with the jets you have but those pictured have adjustable flow nozzels and you want to make sure they are all open. It could be that your booster pump is too big for the number and size jets you have.

 

[bhunjp]

The breaker does not trip on it's own. I have to manually flip the breaker on/off to get the blower to come back.

I am going to talk to airsupply and will report what they think the issue could be.

 

[bhunjp]

I talked with the Silencer (airsupplyflorida.com) folks and they were very helpful. It was easy to get a hold of a technical rep. He even gave me his cell phone.

carolina pool - you were right

The airsupply guy said my pump is pushing water into the air line which is causing too much back pressure and thus the blower overheating.
He said I need to get more water flowing through the jets. The jets are all 20yr old so their condition is pretty bad. I had to smash an old jet with a hammer and pry it out. Fun.
I found replacements (Hayward Jet Air III). I replaced one jet but that didn't help so I am in the process of getting more and hopefully some hi flow jets might help.

The airsupply guy also said my blower was way over sized. I have a 2hp and he recommended a 1hp for my 5 spa jets. The 2hp was what the builder installed. I guess they went overkill.
I just bought the blower to replace the fried old one. I have 30days to return it - so I'm good.