Heating issue after water change - won't go past 96 degrees

[Dommer]

Hi,

I replaced the water 2 days ago to take advantage of a few days of "warm" weather. 

Tub is a Hotspring Vanguard.

After restoring power, tub seemed to be heating up normally.  Checked yesterday and it was up to 96 degrees, and figured it would be ready for a soak tonight.  Went out to check tonight, and see that it's still at 96 (with a set temp of 100). If I lower the temp past 96, the green light goes off, but I don't hear the click of a relay (think I used to previously hear this.).  Temps have been in 30-40 degree range for past few days.

Any troubleshooting suggestions?  Read somewhere that my filters could be a cause (filters are a little over a year old). 

Thanks!

[Kev B]

Is voltage at the heater? Is there an error message? Where does the voltage stop? A troubleshooter uses a meter, so without that it is a shot in the dark guess.

[Dommer]

Thanks for the reply.

I will test the voltage with a meter, didn't have time last night to open up the panel.

Thought that it was odd that the tub did warm up to a point, but is not going any higher, which would indicate that the heater is functioning, no? 

Further research had me thinking that the issue could have been caused by an air lock, and I did notice some large bubbles escape when I removed the filters last night.  Temp was the same this morning when I checked, and I did put run a hose down the filter tube.  Will check again tonight when home.

Thanks

[Kev B]

 Could be a dead heating element and the heat from the motor alone can keep the temp from dropping.
 Also, check out www.backyardplus.com great site for parts and the tech assist guys are great there.

[Dommer]

Issue resolved.  Not sure if this was caused by improper filling technique (not through the standpipe) causing an airlock. 

Killed power for 45 minutes, and removed filters.  Powered back up and got it up to 100 without issue.

Learned my lesson for the next water change.

[Dr. Spa™ Ret.]

99.999% of the time, when a pump is air locked, there's a bubble of air inside that prevents any and all water from flow through it. If there's any water flowing, there's no air lock.

[Kev B]

 Glad you got it, i did not think of the flow issue because you said it went to 96 degrees which would generally mean it would never reach 96 if you filled it with cold water and there was an airlock from the start unless you filled it from the hot water of the house. Enjoy!