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SUS304 FILTER SCREEN OD=18.5mm
Manufacturer Resources
Product Specs
- Product Group:
- Washroom/Bath Accessories
- Product Subgroup:
- Parts and Accessories
- Product Type:
- filter screen
- Department:
- Plumbing
TOTO THP4389 – Frequently Asked Questions
1) What exactly is the TOTO THP4389 part?
THP4389 is a filter screen for a TOTO thermostatic valve unit. It is the small inlet strainer that catches debris before it reaches the mixing cartridge, not the cartridge itself.
2) What size is the TOTO THP4389 filter screen?
The screen has an 18.5 mm outside diameter. Measure the screen you are pulling out of the valve inlet across its rim; if it comes out at roughly 18.5 mm, THP4389 is the matching size.
3) Is the TOTO THP4389 screen stainless steel or plastic?
The mesh is SUS304 stainless steel, so it stands up to constant hot and cold water contact and won't rust out the way a plated or plastic strainer can. That matters in hospitality and multi-family work where these valves get flushed and serviced repeatedly.
4) My TOTO thermostatic shower valve is running cold or losing pressure. Does replacing the filter screen fix that?
A clogged inlet strainer is a common cause of low flow or a thermostatic valve drifting cold on one side, because the mix depends on balanced supply pressure. THP4389 is the SUS304 screen for that inlet. If the screens are clean and the problem persists, the thermostatic cartridge itself is the next item to look at, not the strainer.
5) What part number do I order for the TOTO thermo unit filter screen?
Order by TOTO manufacturer part number THP4389. That is the only configuration of the screen, so there are no finish or size choices to specify.
6) Should I order more than one THP4389 screen for a shower valve rebuild?
Thermostatic valves take a strainer on each supply inlet, hot and cold, so a full clean-out usually means two screens per valve. THP4389 is sold as the individual screen, so count your inlets and order accordingly. Property managers servicing a run of identical TOTO valves generally keep a few spares on the cart.
How fast can I get the TOTO THP4389 delivered?
Most orders ship the same day from our distribution partners, with quick delivery throughout the
continental
U.S.
Need it urgently? Contact Us for expedited shipping options.
Can I return it if it doesn’t work for me?
Yes—ZenSupply offers a hassle-free return policy. If the product isn’t the right fit,
reach out to our support team for a return authorization or setup a return by following our return instructions.
Does the TOTO THP4389 come with a warranty?
Absolutely. The TOTO THP4389 is backed by a manufacturer’s warranty.
For full warranty terms, check the product documentation or Contact Us.
How do I get technical support or installation help for the TOTO THP4389?
You can call, text, or email our expert support team for fast answers. We’re here to help with
product
selection,
installation tips, and troubleshooting. Contact Us
Why buy the TOTO THP4389 from ZenSupply?
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and
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every order.
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