I was given a 1993 CAL SPA 5 person hot tub with 16 jets, which did not have a pump or a pack in it. So I put in a Waterway Executive high performance 56 pool & spa pump that is 4hp and an APOLLO SPAS 10,000 MAXI-POWER Thunderbolt energy module (pack) with a heater. It operates on 220 volts. The problem is when running it on high it does not have enough pressure. I have checked for leaks and blockages and have found none. Also, the air venturies don’t do anything when opening them. I ran some water through them and now the lines have water left in them. Running the pump on high does not siphon the water out. Any help would be appreciated.

First of all a 4hp pump is really overkill for only 16 jets, I wouldn't have gone over 2.0hp for that situation...however you may have an air lock in your system that you simply need to bleed out, run the pump on low speed and open up the discharge union slightly until you get a tiny drip of water and allow to run like that for about 30 seconds, then activate your high jets to see if there is any change.

Thanks for your reply Top Tec; I have bleed the system and it still does not have enough pressure coming out of the jets. It also will not suck air through the air ventures when they are opened. I have checked them for blockage by blowing compressed air through them.

not meaning to be a smart arse, but are the shut off valves ( if fitted ) open after replacing the pump? if they are slice (push/pull) it is possible that the gate has remained in the pipe and the handle pulled loose, effectively leaving the pipe blocked or partially blocked

Alacy thanks for your reply. I chave checked the valves and they are open. As for the ventures not working it turns out to be bad seals on the jets and I have them on order.