I have a 20 year old hot spring highlife spa. I'm currently having troubles with the recirc pump. Over the past two years I've installed two silent flow 5000 and now two of the smaller pumps issued by hot spring. The dealer hasn't been any help in solving the problem so I'm looking for suggestions on how to trouble shoot.

When replacing the pumps the water from the tub flows freely from both the inlet and outlet lines so I don't believe there is any blockage. Any suggestions?

How's your water chemistry?

I don't check it very often, just add chlorine after each use. When I do check it, it is typically OK --- ph is fine, etc.

Is the pump on 24 hours or just when the thermostat calls for heat?

Bad water chemistry can destroy a pump seal in a year which would in then destroy the pump itself. Check your water balance weekly.

This is not the jet pump but a small recirc pump with sole purpose to pump water through the heater. The pump has a magnetic connection between motor and impellar. I believe it runs full time and provides the sole source of water thru the heaters.

I read from another post that calcuim build up in the heater can restrict flow and cause pump failure. Is this true. Is there a way to check the heater for blockage. As I stated earlier, water seems to flow freely when I changing out the pumps.

Thanks for the previous replys.

I took the heater box (approximate 10" by 8" by 5" stainless steel box) which contains two heater elements out this weekend and looked inside the box. Once again, water flowed through each of the lines as I unhooked them from the heater and also from the recirc pump. The box itself was perfectly clean with no sign of corrosion or blockages. Therefore, it seems the problem with the recirc pumps isn't the heaters and must be on the intake side (filters) or electrical. Is there an electrical problem that can cause the pump failures? If so, is there a way to check for them?

You could have excessive or sporadic power to the pump. The volt and amp ratings should be on the pump, both of which could be checked with a meter.

Take the circulation pump apart and look for sign of corrosion or scaling. Don't get too hung up on the pipes being clogged, as that wouldn't ruin the little pump anyway.

I've checked both upstream and downstream and both are clear. The pump impeller and housing are clean and the impeller moves freely in the housing.

I had a spa tech come out and inspect the spa and he didn't find anything wrong so I hooked up yet another new Laing pump. It is working and the spa is once again at temperature. However, I checked the pump after a day or so of operation and it was very hot to the touch. Concerned that the problem might be in the spa wiring, I hooked the pump to my standard GFI outside recepticle. After some time I checked the pump again and it was still hot but didn't seem to be as hot as when plugged directly into the spa receiptical.

Should the recirc pump be hot to the touch. I haven't checked the amps yet but plan to do that this weekend. Since I've now tried two power sources for the pump I'm don't think the spa wiring is the problem but will check it anyway.

Any other suggestions?

It runs very hot to the touch.

I sincerely want to thank all of you who have posted responses to my questions. The information has been very helpful and this website has provided a tremendous service to me.