Hayward heater if code

Hayward makes a range of pool filters, and only some of these filters require backwashing. The filters that do require backwashing are often fitted with the Hayward Vari-Flo multip...

Hayward heater if code. The Hayward Heater HS code indicates that either your water temperature has exceeded a maximum of 104°F or the water temperature is changing at an unusual rate (faster than 6°F in 60 seconds or less while the heater) is on and firing.

Feb 7, 2020. #3. I have the same issue. I have turned off the breaker and the code persists. From what I have read this is a common issue (my heater is only 6 month old) . I don't use my keypad to control the heater (its controlled by the OmniLoigic controller). Anyone have an opinion if its worth replacing the keypad if I always control via ...

Long time lurker, first time poster. I had a brand spanking new H500fd heater installed this past fall by the local pool company. They wouldn't touch the electric or gas so it just sat in the pool equipment room all winter waiting for the weather to turn nicer.Hayward 400 bo code. texasstig. Mar 13, 2021. bo code hayward heater failure - remote not firing heater. Jump to latest Follow Reply. Forums. Equipment - Build, Use, and Repair. Everything Else. T.The hs code for hayward pool heaters is the classification number assigned to these products for international trade purposes. Hayward pool heaters fall under hs code 8419. Consequently, this code is used to facilitate smooth customs clearance and to ensure accurate tracking of imports and exports of these products globally.April 9, 2023 by William. Hayward pool heater IF code basically signifies the ignition failure of your heater system. The major reasons for Hayward pool heater code IF/ignition failure include lower gas supply, clogged filter, and malfunctioning of the gas and plumber valve. Also, a faulty transformer, defective flame sensor, bad igniter, and ...Be the first to know. Email [email protected] to get notified. Explore Hayward Pool for premium pool equipment, accessories, and supplies. Discover product details on maintenance, filtration, pumps, heaters, cleaners, and chemicals.For example, if the date code is 0919, it means the heater was manufactured in September of 2019. Where to Find the Serial Number. The serial number can be found on the heater's rating plate, which is usually located on the inner front panel or on the side of the heater. ... If your Hayward pool heater isn't working as it should, don't ...Common Causes of the H5 Code. When your pool heater displays the H5 code, it typically occurs due to a few common reasons. Troubleshooting h5 code in other pool equipment can help identify the issue. Common misconceptions about h5 code in Hayward pool heaters include thinking it is solely related to a faulty igniter or gas valve.

Availability: In Stock. $129.99. Add to Cart. #16. Hayward - IDXMOD1930 Ignition Control Module for H-Series Above Ground Pool Heater. SKU: 615033. Details: Hayward IDXMOD1930 Ignition Control Module for H-Series H100ID1 and H100IDP1 Above Ground Pool Heaters. Availability: In Stock. $499.99.Hayward pool heaters display an “if” code when the pressure switch is not closed. This is caused by insufficient water flow, closed valves, air in the system, or a clogged filter. It is important to identify and fix the issue …Jan 19, 2010 · On 1/27/2010 at 7:57 AM, txpoolguy said: CE code indicates "Communication Error". Problem is communication between integrated control board and display board. Display board (DB) is the one mounted on the backside of the keypad. Integrated control board (ICB) is the one back in the heater behind the display board. 2. Clogged Water Filter. 3. Incorrect Setting of the Thermostat. 4. Damaged Water Temperature Sensor. 5. Incorrect Position of Bypass Valves. FAQ: Why is the …Install a Hayward replacement for any competitor's pump, heater, filter or other select items. SNAP Snap clear photos of the before & after installation products, the Hayward replacement serial number, and the installation invoice.The breakdown the H400FDN model code is as follows: (1) H identifies the heater as part of the Hayward H-Series pool heater range. (2) 400 defines the size of the heater in BTU and shows that the unit is rated at 400,000BTU. (3) FD identifies the unit as a Forced Draft Low NOx Heater. (4) N identifies the unit is designed for a Natural Gas fuel ...

Minimum inlet gas pressure. 10.0”. Using a Manometer, take a measurement at the inlet port on the gas valve for both Static Pressure (heater o ) & Load Pressure (heater red); readings should be within the values on the heater data plate. Then measure the Manifold Pressure from the outlet port on the gas valve. Inlet Port.The document provides troubleshooting information for Hayward pool heaters, including: 1. Error codes and their meanings to help diagnose issues, such as a blocked ...You need to put the heater in STANDBY Mode to get the bO code on the heater display. Press the mode button once to get the heater in STANDBY Mode. First, press and hold on to the Down key. Then, press and hold down the MODE key as well. You need to keep holding both keys for about three seconds. At this point, the “bO” message should appear ...Summary of Contents for Hayward H300FD. Page 1 POOL AND SPA/HOT TUB HEATERS H150FD, H200FD, H250FD, H300FD, H350FD, H400FD & H500FD MODELS OWNER'S MANUAL FOR YOUR SAFETY WARNING: If the information in these instructions is not followed exactly, a fire or explosion may result causing property damage, PRINTED 10/24/2011 AT 1:13 PM injury, or death.Are you experiencing a LO code on your Hayward H-Series pool heater? If so, give this video a watch for a few basic tips on how to work through the issue you...SPECIFICATIONS AND DIMENSIONS H500FD H400FD H250FD H200FD H150FD BTU/hr 500,000 399,900 250,000 199,900 150,000 Thermal efficiency 83% 84% 84% 83% 82.7%

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What is the if code on the Hayward pool heater? The IF code on the Hayward pool heater indicates an ignition failure, preventing the heater from starting. Why is my Hayward pool heater not heating? It appears the issue may be with your gas supply, a failing pilot generator, a bad gas valve, or a blockage in the pilot assembly.The hs code for hayward pool heaters is the classification number assigned to these products for international trade purposes. Hayward pool heaters fall under hs code 8419. Consequently, this code is used to facilitate smooth customs clearance and to ensure accurate tracking of imports and exports of these products globally. Understanding the ...Feb 4, 2020 ... SUPPORT ▻ Buy me a coffee: https://www.buymeacoffee.com/fixitwithjake Pool/Spa Heater Repair- Error Code 05 Flume Sensor 1: ...We have 4 Hayward H400FDN manuals available for free PDF download: Troubleshooting Manual, Service & Installation Manual, Owner's Manual Hayward H400FDN Service & Installation Manual (64 pages) POOL AND SPA/HOT TUB HEATERSPosted April 16, 2010. The "LO" code means "Loop Open", referring to your safety loop switches. Most likely it's your pressure switch that's open due to low water flow usually caused by a dirty filter. The "60" code is really "bO" meaning "bypass operation" in which your heater's internal thermostat is bypassed so as to control the set ...The control board oversees the operation of your heater, including monitoring temperature and safety features. In short, the Hayward Heater bD Code means there is a problem with the control board located on the right side of the heater. This can be caused by an open FC4 Fuse, faulty wiring, or a secondary high voltage fault.

Remove front & rear panels Remove wires from limit switches. Step 13. Remove the 4 screws from the bottom of the front and rear panels and pull up and out to remove each one. Step 14. Use needle nose pliers to remove the 2 red wires from each of the high limit switches. Remove wires from water pressure switch.The major reasons for Hayward pool heater code IF/ignition failure include lower gas supply, clogged filter, and malfunctioning of the gas and plumber valve. Also, a faulty transformer, defective flame sensor, bad igniter, and incorrect thermostat temperature setting are the root.Hayward Pool Heater Ao Code . When it comes to pool maintenance and safety, one of the most important considerations is making sure your Hayward Pool Heater is running properly. The Ao code on your Hayward Pool Heater indicates that a temperature or pressure switch has been activated due to an unsafe condition in the heater. If you see …The hayward pool heater if code is an error message that appears on the control panel of your heater. This message signals that there’s a problem with the ignition system or the flame sensing rod. The if code typically appears when your pool heater tries to start but fails to ignite.Here you’ll gain easy access to information regarding your favorite Hayward products. Whether you are looking for a Quick Reference Guide, troubleshooting steps, or simply wish to view one of our product support videos, you have come to the right place.Diagnostic Codes For Hayward Heat PumpBest Answer: Turn off the power to the Hayward pool heater. Locate the CE code on the display panel. Press and hold the “Reset” button for three seconds. Press the “Up” or “Down” arrow keys to scroll through the menu options. Select the “Service” menu option. Enter the four-digit service code. Press the “Enter” button.USE ONLY HAYWARD GENUINE REPLACEMENT PARTS Hayward Pool Products 620 Division Street, Elizabeth NJ 07207 Phone (908)-355-7995 ... and a conventional and solar heater. Both manual and automatic (programmed) ... Check local codes for other restrictions. The actual amount of chlorination requiredHayward 150 heater through an AO code which often means a blower switch. This was $28 and super easy to install. Seriously, I've been more difficulty plugging Lampson to outlets and changing the switch. Seriously, I've been more difficulty plugging lamps into outlets than changing this switch.Fixed our problem for less than $30.Install a Hayward replacement for any competitor’s pump, heater, filter or other select items. SNAP Snap clear photos of the before & after installation products, the Hayward replacement serial number, and the installation invoice.

Universal HC Series - Dual Fuel 400k BTU. Hayward. SKU: HDF400. The industry's smallest footprint heater allows replacement of almost any heater in an existing pad with the efficient reliability of the new Universal HC Series dual-fuel technology heater from Hayward®. Add to Compare. Add to Export. Overview.

Pool Heater Service Call - Hayward Heat Pro Heat Pump with LP Error on display. LP is Low Pressure. We found a leak on the filter dryer, discussed with home...The gas pressure to the Pentair pool heater often gets obstructed due to clogged gas pipes, incorrect pressure settings, and turned off gas valves. These factors prevent the gas from reaching the heater and performing properly. It also causes the heater to shut down completely and display the E05 code on the Pentair heater.This quick video is a great resource for basic understanding of your Hayward gas heater.Our network of certified personnel can help you build your pool, recommend a product, repair a faulty product, and test your water. Find a professional near you. Hayward offers environmentally responsible, cutting-edge pool and spa equipment for residential and commercial, in-ground and above-ground pools.For more information, questions or concerns: Permit Center. Ask Us question or Start an Application. 005_Residential-Water-Heater-Replacement121322.pdf.The electric heaters fit into compact spaces — even under spa skirts or steps. Like all Hayward heaters, they are easy to install and service. • 304 stainless steel tank, • 304 stainless steel threaded head, safety sensor electric heating element, • Service-ease design gives simple access to internal controls, • Heater on indicator light,Turn off your heater, wait a few minutes, then power it back on. If the AO Code persists, move on to the next step. Check the wiring: Inspect the wiring between the blower vacuum switch and the control board. Look for loose connections, damaged wires, or other signs of wear and tear. If you spot any issues, call a professional for assistance.I have Hayward H150FDN Universal H-Series, Low NOx, 150,000 BTU, Natural Gas, Pool and Spa Heater and I am getting a LO code with is a flow problem. I have my intermatic timer set for 755am to turn on and give my equipment power, then at 8am the Hayward pump turn on. Can the heater be on...

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When my Hayward heater started displaying the "AO" error code, I immediately felt a sense of panic. As a homeowner who relies on my heater to keep the poolBefore the codes appear, I see a temp over 100 for a split second and then a temp of 75 which is consistent with the actual water temp. I think there is a total of 3 sensors on the header. I believe the reading of 78 would be from the sensor for the water entering the heater and the quick reading (and wrong one of over 100) is coming from a ...The Hayward Municipal Code is updated on a regular basis. Review the Municipal Code here: Hayward Municipal Code. For additional information on the Hayward Municipal Code, please contact the Office of the City Clerk at 510.583.4400. Traffic Code & Regulations. Traffic codes are regulations governing parking and traffic movement.ManualsLib has more than 81 Hayward Swimming Pool Heater manuals. Click on an alphabet below to see the full list of models starting with that letter: A C E H S T W. Popular manuals. 43 pages. HeatPro® Owner's Manual. 12 pages. H100ID1 Installation & Operation Manual. 16 pages.Scan the QR code for an updated list of eligible SKUs for the Totally Hayward Program. Get bonus rewards points when you bundle 4, 5 or 7 qualifying ... must be a Hayward heater, heat pump, cleaner, sanitization system or control. Lighting and T-CELL purchases do not countThe heater attempts to light the burner three times before displaying the IF code and shutting down. The code protects the heater from damage caused by a gas buildup or other ignition-related problems. Common Causes of the Hayward Heater IF Code. There are several reasons your Hayward heater may be displaying the IF code.View and Download Hayward AquaRite S3 technical training manual online. Salt Chlorine Generator. AquaRite S3 swimming pool filter pdf manual download. ... Adjust Heating Setting Step 5 Step 6 Heater Extend will Cool Down will not temporarily suspend allow the pump to the filter pump timer be shut off for 5 and allow the pump to minutes while ...Hayward Insights provides expert advice, tips, and industry updates to help pool owners and enthusiasts with their swimming pool experience. Gain insight. Support. ... Phase Heaters: 1.0000: Pool Type: In Ground: Product Dimensions: 24 " x 34 " x 29.5 "Product Height: 24 in: Product Length: 29.5 in: Product Weight: 195 lb: Product Width:First, Power cycle the Omni Controller by selecting the power button at the bottom left of the screen, followed by pressing the shutdown option. Once the controller display is shutdown, turn power off using the breaker, wait 60 seconds and power back up. Wait 3 minutes and then check to see if the connection has been re-established.Install a Hayward replacement for any competitor's pump, heater, filter or other select items. SNAP Snap clear photos of the before & after installation products, the Hayward replacement serial number, and the installation invoice.Plaster. Chlorine. Salt Water Generator. SWG Type. Pentair Intellichlor IC-60. Aug 27, 2021. #2. Welcome to TFP. b0 code simple means the heater is being controlled by the remote 2 wire connection to your Prologic and will not respond to the keypad controls.The Universal H-Series 400,000 BTU Natural Gas Pool & Spa Heater from Hayward provides reliable, long-lasting comfort for pools and spas with a surface area up to 1,200 ft. Built with a durable cupro nickel heat exchanger, it offers exceptional protection against corrosion and premature failure caused by unbalanced water chemistry, ensuring you ... ….

Hayward Heat Pump Lock Out FeatureHayward products including, quick reference guides, troubleshooting steps, and product support videos.Step 1 Step 2 Press the 'MENU ICON' button to place the heater in 'STANDBY' mode. Step 3 Press and hold the minus & plus buttons for. Hayward HDF400 | Universal HC Series Heater Troubleshooting Guide - Page 11. setting the max temp lock-out set point, the LEDs & display should flash rapidly.You are seeing a code of 888 on your pool heater. To better assist you a photo of the data plate with a Model and a serial number. Will allow me to pull your units specific information. I specialize in Pool & Spa Heat Pumps. I am a Licensed HVAC Contractor. ... Hi , I have a Hayward model H250ED2 pool heater, ...Hayward W3H300FDN Universal H-Series Low NOx 300,000 BTU Natural Gas Residential Pool and Spa Heater with Bundle* Warranty Better Buy Pool Supply will provide you with the Full 2 Year Manufacturer's Warranty plus 1 Year Installation Warranty upon installation by our professionals. From the Manufacturer The Universal H-Series is an energy efficient, high performance, installation […]code serial number over all I wish that I could send you a short video.it is blinking this. the blink is a fast random blink. it was installed in 2013 and has been working fine. yesterday I went to get in the hot tub for the first time this season. so when I turned on the breaker, this is what I got.almost looks like it is trying to power up. but I don't know. did those photos come across okay?Hayward City Hall 777 B Street Hayward CA, 94541-5007 Phone: 510-583-4140 Website: www.hayward-ca.gov Permit Center Hours: Please see website for operating hours Type “B” vent termination minimum is 1 foot above roof in approved cap.How do I reset my Hayward pool heater? Resetting a Hayward pool heater is a very simple process. Just follow these steps: 1) Turn off the power to the pool heater by shutting off the breaker switch. 2) Disconnect the wires from the terminal block. 3) Remove the cover of the terminal block.Hayward HeatPro Heat Pump Parts HP21404T, HP21004T, HP21254T, HP31154T. Starting from $44.99. Delivery. FREE Shipping with +$100 Purchase. Shop Now. Hayward Heatmaster HM Models 280-406 Pool Heater Parts. Starting from $28.99. Delivery. FREE Shipping with +$100 Purchase.Home - Trouble Free Pool | Trouble Free Pool Hayward heater if code, Hayward products including, quick reference guides, troubleshooting steps, and product support videos. ... Heater required kW : Heater required BTU/hr : Water weight kg : Water weight Lbs : ... Scan the QR code to send us a quick information request. Include your phone/messaging contact number and country in your message., Preventing Future LO Codes. To avoid encountering the Hayward Heater LO Code in the future, consider implementing these preventive measures: Regular Maintenance: Stay on top of regular maintenance tasks, such as cleaning or replacing your pool filter and inspecting your plumbing system for blockages., Start heater again. Does low side pressure drop below 30 psi for R-22 unit or 80 psi on a R-410A unit? Figure C. Replace LP switch. See Note 2 below NO Abandon existing switch on Hayward R-22 units. Replacement switch is a screw on switch. Use a swivel tee on the low side access port. On Summit and R-410A (4T) Hayward units the existing switch ..., View online or download Hayward H400FDN Owner's Manual, Troubleshooting Manual ... Brands; Hayward Manuals; Heater; H400FDN; Hayward H400FDN Manuals. Manuals and User Guides for Hayward H400FDN. We have 4 Hayward H400FDN manuals available for free PDF download: Troubleshooting ... Diagnostic Codes and Part Numbers. 19. Troubleshooting Guide. 20 ..., Hayward Insights provides expert advice, tips, and industry updates to help pool owners and enthusiasts with their swimming pool experience. Gain insight. Support. ... Phase Heaters: 1.0000: Pool Type: In Ground: Product Dimensions: 24 " x 34 " x 29.5 "Product Height: 24 in: Product Length: 29.5 in: Product Weight: 195 lb: Product Width:, Universal H-Series Natural Gas 400,000 BTU Low NOx. Hayward. SKU: W3H400FDN. The Universal H-Series is an energy efficient, high performance, installation adaptable commitment to the pool service professional. Add to Compare. Add to Export., PREMIUM PERFORMANCE: The Hayward Universal H-Series 250,000 BTU Natural Gas Heater delivers fast premium heating performance for years of reliable, long-lasting comfort. CORROSION PROTECTION: The Universal H-Series boasts exceptional protection against corrosion and premature failure caused by unbalanced water chemistry. , Heater will not power up Pages 14-22 Open FC1 and/or FC2 Fuse Pages 23-24 Open FC3 and/or F1 Fuse Pages 25-28 Open FC4 Fuse Pages 29-31 Diagnostic Codes Page 32 BD Code Pages 33-34 EE and CE Codes Page 35 IO and SB Codes Page 36 SF and HS Codes Page 37 ... Hayward Part # FDXLFSKF30 (Qty. 10) Step 1:, Our network of certified personnel can help you build your pool, recommend a product, repair a faulty product, and test your water. Find a professional near you. Hayward offers environmentally responsible, cutting-edge pool and spa equipment for residential and commercial, in-ground and above-ground pools., Dealing with the Hayward Heater HS IO code can be challenging, but with the right knowledge, preventive measures, and a willingness to explore advanced options, you can maintain a reliable and safe heating system for your pool or spa. Remember that safety should always be a top priority when working with gas appliances, and don’t …, Check below for water heater specials and rebates in the greater Hayward area: Pacific Gas & Electric Company (PG&E) Water Heater Rebates. PG&E offers a $125 rebate for gas storage water heaters with an efficiency rating of .67 or more. PG&E offers a $300 rebate for electric heat pump water heaters with an efficiency rating of 2.0 or more., Dec 30, 2022 ... Hayward Pool Heater LO Code? Watch This ... Hayward H400 Pool Heater IF Error Code ignition Failure (IDXLFLS1930) Flame Sensor Replacement., My pool heater would not fire and was showing the LO (low flow) code. This shows where the adjustment knob is on the pressure switch and insight into how to ..., Pool heaters work very straightforwardly: they generate heat to raise the water temperature. As long as they have a reliable water supply, the heater will not overheat. That's why your unit will display the LO code when there's something wrong with the water supply. The LO code signifies that there's a low water pressure condition. […], Start heater again. Does low side pressure drop below 30 psi for R-22 unit or 80 psi on a R-410A unit? Figure C. Replace LP switch. See Note 2 below NO Abandon existing switch on Hayward R-22 units. Replacement switch is a screw on switch. Use a swivel tee on the low side access port. On Summit and R-410A (4T) Hayward units the existing switch ... , Universal H Series Heaters® Troubleshooting: Hayward H250FDP | Universal H Series Troubleshooting Guide - Page 19 Diagnostic Codes Below is a list of all Diagnostic Codes for the UHS Heater. Troubleshooting Steps for each Code are covered on the following pages. Diagnostic Code AC AO BD CE EE HF HS IF IO LO PF SB SF, Remove front & rear panels Remove wires from limit switches. Step 13. Remove the 4 screws from the bottom of the front and rear panels and pull up and out to remove each one. Step 14. Use needle nose pliers to remove the 2 red wires from each of the high limit switches. Remove wires from water pressure switch., Here you’ll gain easy access to information regarding your favorite Hayward products. Whether you are looking for a Quick Reference Guide, troubleshooting steps, or simply wish to view one of our product support videos, you have come to the right place. ... iPad Heater Navigation - OmniLogic Automation System. iPhone Favorites - OmniLogic ..., Good afternoon; how are you this afternoon? I am sorry to hear about your BD code on your Hayward Heater. I am sure this is frustrating. We will start from the beginning; some of this may be repetitive. BD Code means Bad Board or Secondary High Voltage Fault. Remove FC4 fuse and measure continuity. Let me know if that fuse is the one you ..., On 1/27/2010 at 7:57 AM, txpoolguy said: CE code indicates "Communication Error". Problem is communication between integrated control board and display board. Display board (DB) is the one mounted on the backside of the keypad. Integrated control board (ICB) is the one back in the heater behind the display board., The Hayward Pro Logic is a multifunction pool controller used to fully manage your pool/spa sys- ... valves, lighting, heaters, and chlorination. Although the Pro Logic is easy to use, it is important to completely read through this operating manual before ... lons (95,000 liters). Check local codes for other restrictions. The actual amount of ..., Enter a postal code to find the nearest Hayward authorized pool professional. ... Heaters (not including Heat Pumps) Heat Pumps. Lighting. Pumps. Variable Speed Pumps ... , My Hayward H400K heater is showing an AO code and will not kick over and begin heating.....it appears to be working fine. Cannot smell any propane but the tanks are 60% full....everything sounds fine, it just not kick on and begin heating....Geoff Read More, This integrated control board is designed to use with Hayward Universal H-Series Low NOx induced draft heater models H250IDL2, H350IDL2, H400IDL2 and also compatible with Hayward Universal H-Series Low NOx induced draft heater. New part incorporated on all IDL Heaters built after 9/20/04., Hayward 150 heater through an AO code which often means a blower switch. This was $28 and super easy to install. Seriously, I've been more difficulty plugging Lampson to outlets and changing the switch. Seriously, I've been more difficulty plugging lamps into outlets than changing this switch.Fixed our problem for less than $30., 301 Moved Permanently. nginx/1.18.0 (Ubuntu), Jun 13, 2020 ... Temperature sensor error , quick vid of changing water pressure switch. Sorry for crapy video no editing system yet., Installation in Combination with Solar or Gas Heaters 10 Using an External Controller 11 ... Meaning of Display Codes 18 Troubleshooting 19 Requesting Assistance or Service 21 Maintenance 22 Winterizing 22 Heat Pump Pool Heater Limited Warranty 23 International Warranty 24 Warranty Card Registration 25. Thank you for buying a Hayward pool heat ..., SPECIFICATIONS AND DIMENSIONS H500FD H400FD H250FD H200FD H150FD BTU/hr 500,000 399,900 250,000 199,900 150,000 Thermal efficiency 83% 84% 84% 83% 82.7%, Hayward pool heaters are known for their durability and ease of use. They are designed with a cupro-nickel heat exchanger that resists corrosion and lasts longer than traditional copper exchangers. Hayward heaters also come with a digital control panel that allows you to adjust the temperature and settings easily., The heater must be installed such that the location of the exhaust gas vent assembly outlet relative to adjacent public walkways, adjacent buildings, openable windows, and building openings complies with the National Fuel Gas Code (ANSI Z223 ; Hayward HDF400 | HDF400 User Manual - Page 13 heater may be installed on either non-combustible heater., Many choose Hayward pool heaters to keep their pool water comfortable and warm. However, sometimes these heaters can experience issues that require a reset. To reset your Hayward pool heater, you’ll need to turn off the power, wait a few minutes, and then turn it back on again. This simple process can resolve many common […], PitschPlumbing. Generally, LO refers to the pressure switch, water pressure. This can be caused by either the diaphram in the flow switch has failed or the filters is clogged and/or pump is unable to make enough pressure to make the switch. Open the front panel of the heater and look up in to the right. You will see a round part with 2 wires ...