Replacing a Kunkle or Apollo Safety Valve?
We cross-reference Kunkle and Apollo safety valves to Aquatrol equivalents — matched by ASME code stamp, set pressure, rated capacity, and connection size.
Get a Cross-Reference Quote Configure a ReplacementWhy Facilities Are Switching from Kunkle to Aquatrol
Kunkle safety valves have been an industry standard for decades, but supply chain disruptions, long lead times, and acquisition-related changes have made it harder to source them reliably. Aquatrol manufactures ASME-certified safety and relief valves that match or exceed Kunkle specifications — same code stamps, same pressure ratings, same connection sizes.
As an authorized Aquatrol distributor, Safety Control Valves carries over 4,000 pre-sized valve configurations ready to ship. We also configure custom valves to match your exact Kunkle nameplate specs when a direct catalog match isn’t available.
How We Cross-Reference Your Valve
There is no official OEM-to-OEM cross-reference table between Kunkle, Apollo, and Aquatrol. We maintain an internal database built from years of field replacements. Here’s how we match your valve:
Send Us Your Nameplate
Photograph the valve nameplate or provide the Kunkle/Apollo model number, set pressure, and capacity.
We Match the Specs
We verify ASME code section, set pressure, service medium, rated capacity, and connection type.
Get Your Aquatrol Match
We recommend the Aquatrol series and configuration that meets or exceeds your original valve specs.
Ships for $25 Flat
Order online or through our team. Every order ships for $25 flat-rate — no account required.
Key Specifications We Match
When replacing a Kunkle or Apollo safety valve, these are the critical parameters that must be matched for a code-compliant replacement:
| Specification | Why It Matters | Where to Find It |
|---|---|---|
| ASME Code Section | Section I (boilers), Section IV (heating), or Section VIII (pressure vessels) — determines certification requirements | Stamped on nameplate |
| Set Pressure (PSI) | Must match the system’s Maximum Allowable Working Pressure (MAWP) | Stamped on nameplate |
| Service Medium | Steam, air/gas, or liquid — determines seat material and valve design | Nameplate or system documentation |
| Rated Capacity | Replacement must have equal or greater relieving capacity (BTU/hr or CFM) | Nameplate or engineering data sheet |
| Inlet/Outlet Size | Must match existing pipe connections — typically NPT, flanged, or tri-clamp | Measure existing connections |
| Connection Type | NPT threaded, flanged (150#, 300#, 600#), or sanitary tri-clamp | Visual inspection or drawings |
| Body Material | Brass/bronze, stainless steel, or carbon steel — must be compatible with process media | Nameplate or material cert |
Aquatrol Series Overview
Aquatrol manufactures four primary safety valve series, each designed for specific applications:
| Aquatrol Series | Body Material | Common Applications | Replaces |
|---|---|---|---|
| Series 740 | Brass / Bronze | Boilers, compressors, water heaters, steam systems | Kunkle 6000 series, Apollo 10-600 series |
| Series 741 | 316 SS / Bronze | Chemical processing, sanitary applications | Kunkle 900 series (SS models) |
| Series 742 | 316 SS / Carbon Steel | High-pressure industrial, corrosive environments | Kunkle 900 series (CS models) |
| Series 743 | Full 316 Stainless Steel | Pharmaceutical, food/beverage, high-purity | Kunkle 900 series (full SS) |
Frequently Asked Questions
Can I replace a Kunkle valve with an Aquatrol without re-engineering?
In most cases, yes. If the Aquatrol replacement has the same ASME code stamp, equal or greater capacity, the same set pressure, and matching connections, it is a code-compliant direct replacement. We verify all parameters before recommending a match.
Is there an official Kunkle-to-Aquatrol cross-reference chart?
No. Kunkle (now owned by Emerson/Pentair) does not publish an official cross-reference to third-party manufacturers. However, experienced distributors like Safety Control Valves maintain internal databases built from years of field replacements. Send us your Kunkle model number and we’ll provide the Aquatrol equivalent.
What about Apollo safety valves?
We cross-reference Apollo safety valves the same way. Provide your Apollo model number, set pressure, and application details, and we’ll match it to the correct Aquatrol series and configuration.
How long does a cross-reference take?
Most cross-references are completed within one business day. If you have a nameplate photo, we can often provide a match within hours. For complex or non-standard configurations, allow 2-3 business days.
Do you carry Kunkle or Apollo parts?
No. We are an authorized Aquatrol distributor. We specialize in matching Aquatrol equivalents to Kunkle and Apollo valves — not in stocking the original parts.
What information do I need to provide for a cross-reference?
At minimum: the existing valve’s model number, set pressure, and what it’s being used for (steam, air, liquid). A nameplate photo is ideal. If you also have the rated capacity and connection sizes, that speeds things up.
Ready to Find Your Replacement?
Send us your Kunkle or Apollo nameplate info and we’ll cross-reference it to the right Aquatrol valve — usually within one business day.
Get a Cross-Reference Quote