Lochinvar · Armor OAN (outdoor)
Lochinvar Armor OAN501PM
The Lochinvar Armor OAN501PM is a outdoor condensing commercial water heater rated 500,000 BTU/hr input at 96% thermal efficiency with 582 GPH recovery at a 100°F rise.
Key figures
- Max input
- 500,000 BTU/hr
- Max CSA output
- —
- AFUE
- —
- Min input
- —
Input is gas energy consumed; output is heat delivered. Never size from input alone.
Lochinvar Armor OAN501PM in practice
The Armor OAN501PM is the 500,000 BTU/hr size of Lochinvar's outdoor condensing commercial water heater line. The printed submittal sizing table lists 500,000 BTU/hr input, 96% thermal efficiency and 582 GPH recovery at a 100°F rise, with a 1" gas connection, 2" water connections, 3" air inlet and 4" vent sizes and a 333 lb shipping weight.
The Armor is a modulating condensing water heater with 5:1 turndown, a stainless steel heat exchanger and the SMART SYSTEM operating control with a built-in cascading sequencer for up to eight water heaters; the product pages list the CON·X·US remote connect option and ENERGY STAR rating on the larger models. The submittal's LP models follow the N-to-L convention with no deration, and the warranty is 5-year limited with 1-year parts coverage.
Best suited to
- Commercial domestic hot water loads near 500,000 BTU/hr input
- Buildings replacing a water heater of similar recovery rate
- Retrofit projects that need the printed connection and vent sizes for planning
Applicability and support
- Model number
- OAN501PM
- Canadian availability
- available
- Production status
- current
- ROMA supplies
- Confirmed at consultation
- ROMA services
- Confirmed at consultation
- Warranty
- Series terms
Where ROMA provides on-site service
On-site service is currently offered in Greater Vancouver, BC, including Vancouver, Burnaby, Richmond, Surrey, Coquitlam, North Vancouver, West Vancouver, New Westminster, Port Coquitlam, Port Moody, Delta, Langley, Maple Ridge, Abbotsford, Chilliwack, White Rock, Pitt Meadows, Tsawwassen, Anmore, Lions Bay, Belcarra, Bowen Island, Mission. Everything else on this site is reference information you can use anywhere in Canada.
Specifications
Published specifications
Values as published by Lochinvar. Units are shown with every value; notes flag conflicting sources or missing figures.
| Specification | Value | Note |
|---|---|---|
| Input | ||
| Input | 500,000 BTU/hr | Per the printed submittal sizing table. |
| Efficiency | ||
| Efficiency (thermal) | 96 % | Thermal efficiency printed in the submittal sizing table. |
| Domestic hot water | ||
| Recovery rate at 100°F rise | 582 GPH | Per the printed submittal sizing table. |
| Venting and air | ||
| Air inlet size | 3" | Per the printed submittal sizing table. |
| Vent size | 4" | Per the printed submittal sizing table. |
| Physical and connections | ||
| Gas connection | 1" | Per the printed submittal sizing table. |
| Water connections | 2" | Per the printed submittal sizing table. |
| Shipping weight | 333 lb | Per the printed submittal sizing table. |
| Operating limits and other | ||
| Turndown | 5:1 | Per the submittal standard features and product page. |
| Configuration | Outdoor condensing commercial water heater | Per the submittal and product page. |
Manuals
Alerts documented for this model
None documented yet.
Frequently asked questions
What are the Armor OAN501PM ratings?
The printed sizing table lists 500,000 BTU/hr input, 96% thermal efficiency and 582 GPH recovery at a 100°F rise.
What turndown does this Armor have?
The submittal and product page print 5:1 turndown for this family.
Does the Armor make domestic hot water directly?
Yes. The Armor is a volume water heater: it heats domestic water directly rather than storing it in an indirect tank, and the printed recovery rate is its domestic-water output.
Questions about the Lochinvar Armor OAN501PM?
Describe what the boiler is doing and get a straight answer about the next step.
On-site service in Greater Vancouver, BC. ROMA lists “Open 7 days” on its site; call to confirm same-day availability.
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Sources and verification
- Lochinvar — Armor Outdoor Condensing Water Heater (OAN201) model page · accessed September 9, 2026
- Outdoor ARMOR Condensing Water Heater Submittal Sheet, OAW-Sub-02 · OAW-Sub-02 · accessed September 9, 2026
- Outdoor ARMOR Condensing Water Heater Installation & Operation Manual, Rev Y · Rev Y · accessed September 9, 2026
Facts checked September 9, 2026. Last updated September 9, 2026. Technical reviewer: not yet assigned.