Replacing a Pentair MasterTemp With a Hayward Heater? What the UHXWPAK1930 Adapter Kit Does
Your old Pentair MasterTemp quit, you found a Hayward heater you like, and then somebody tells you the pipes will not line up. That usually comes as a surprise, and it usually comes after the old heater is already off the pad.
The Hayward UHXWPAK1930 exists for that exact job. It is a water plumbing adapter kit that lets a compatible Hayward heater tie into the pipe stubs your MasterTemp left behind.
What does the Hayward UHXWPAK1930 adapter kit do?
Short answer: it changes where the water inlet and outlet sit on the new Hayward heater so they match the plumbing the Pentair heater was using. You bolt the kit on and connect to what is already there instead of cutting and rebuilding the pipe run.
That saves you the messy part of a heater swap. No new trenching around the pad, no guessing at pipe heights, no waiting on glue to cure while the pool sits down a day.
Why don't Pentair and Hayward heaters share the same plumbing?
The two companies designed their cabinets separately, so the water connections do not land in the same spot. Heights differ, spacing between inlet and outlet differs, and which side the water enters can differ too.
None of that matters when you replace a heater with the same brand and model. It matters a lot when you switch brands. This is the number one reason a straightforward heater swap turns into a plumbing job.
Which heaters is the UHXWPAK1930 compatible with?
It is made for putting a compatible Hayward gas heater onto plumbing that was set up for a Pentair MasterTemp. Before you order, write down two things: the exact model number of the heater coming out, and the exact model number of the Hayward heater going in.
Then check both against the kit before you buy. Heater lines get revised over the years, and a model that looks identical from ten feet away may not use the same connection layout. If you are not sure, send us the two model numbers and we will confirm it for you.
How do you install the UHXWPAK1930?
The plumbing side is straightforward. The gas and electrical side is not a DIY job, so plan on a licensed tech for those steps.
- Shut off the gas at the heater and kill power at the breaker.
- Close the valves on both sides of the heater and drain it.
- Disconnect the unions, gas line, and wiring, then pull the old MasterTemp off the pad.
- Set the new Hayward heater in place and check your clearances before anything gets glued or tightened.
- Install the UHXWPAK1930 adapter kit on the heater's water connections.
- Connect the unions to your existing plumbing and snug them by hand, then check for square.
- Have a licensed gas fitter make the gas connection and a qualified electrician handle the wiring.
- Open the valves, run the pump, purge the air out, and check every joint for drips before you fire the heater.
Is the adapter kit worth it, or should you just re-plumb?
For most swaps the kit wins. Re-plumbing means fittings, pipe, glue, and a chunk of a plumber's day, and labor is where the money goes. The UHXWPAK1930 usually costs less than that time, and the job is done the same afternoon instead of stretching into a second visit.
Re-plumbing makes more sense in a couple of cases. If your existing pipe is old, brittle, or already leaking, you are going to be cutting into it anyway. Same goes if you are moving the heater to a different spot on the pad or upsizing pipe for better flow. In that situation the adapter kit is solving a problem you are about to remove.
What else should you check before swapping heater brands?
A few things trip people up when they change brands, and all of them are cheaper to catch now than after the heater is set.
- Gas line size. If the new heater has a higher BTU rating than the MasterTemp it replaces, your existing gas line may be undersized. A gas fitter can size this in a few minutes.
- Electrical. Confirm voltage and that the existing circuit matches what the new heater calls for.
- Pad space and clearances. Cabinets are not the same footprint. Measure before the truck shows up.
- Bypass and check valves. If your old setup had a bypass loop, make sure it still works with the new connection points.
- Automation. A Hayward heater on a Pentair automation system will usually run on a simple relay or fireman's switch rather than full two-way communication. Worth knowing before you expect temperature control from the app.
The bottom line on the UHXWPAK1930
If you are moving from a Pentair MasterTemp to a Hayward heater and your existing plumbing is in good shape, the UHXWPAK1930 is the part that keeps the job simple. It is a small line item next to the heater itself, and it removes the one step most likely to blow up your install day.
Confirm both model numbers first, have the kit on site before the old heater comes out, and line up your gas and electrical help ahead of time.
Not sure this is the right part for your problem? Reach out and we will help you figure out exactly what you need before you spend money on the wrong thing.