Instruction/ maintenance manual of the product PW Laarsen Associates
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FOR YOUR SAFETY : This product must be inst alled and serviced by a professional service technician, qualified in hot water heater installation and maintenance. Improper installation and/or operation could create carbon monoxide gas in flue gases which could cause serious injury , property damage, or death.
LAARS HEATING SYSTEMS Page 2 SECTION 1. General Information 1A. Introduction ................................................... 3 1B. Heater Identification ..................................... 3 1C. Flow Requirements ................................
Mighty Therm Volume Water Heater Page 3 SECTION 1. General Information 1A. Introduction This manual provides information for the installation and operation of Laars volume water heaters. It is strongly recommended that all application and installation procedures be reviewed completely before proceeding with the installation.
LAARS HEATING SYSTEMS Page 4 1C. Flow Requirements For proper operation, all low volume hot water heaters must have continuous flow through the heat exchanger when firing. The system pump must be capable of developing sufficient pressure to overcome the resistance of the heater plus the entire circulating system at the designed flow rate.
Mighty Therm Volume Water Heater Page 5 Figure 2. Typical Heater Installation with Base for Combustible Floors, Example A. Figure 3. Typical Heater Installation with Base for Combustible Floors, Example B. Figure 4. Typical Heater Installation with Base for Combustible Floors, Example C.
LAARS HEATING SYSTEMS Page 6 2B-1. Combustion Air Supply 1. The heater location must provide sufficient air supply for proper combustion and ventilation of the surrounding area as outlined in the latest edition of ANSI standard Z223.1, and any local codes that may be applicable.
Mighty Therm Volume Water Heater Page 7 maintain clearances and prevent physical damage and separation of joints. 4. Avoid ending heater vents near air conditioning or air supply fans. The fans can pick up exhaust flue products from the heater and return them inside the building, creating a possible health hazard.
LAARS HEATING SYSTEMS Page 8 4. The boiler and its individual shutoff valve must be disconnected from the gas supply piping system during any pressure testing of that system at test pressures in excess of 1/2 psig.
Mighty Therm Volume Water Heater Page 9 Special attention must be given to relief valve settings in installations where the heater is located on the ground floor of a tall building. The static pressure of the system is elevated and could cause the relief valve to leak.
LAARS HEATING SYSTEMS Page 10 2H. Pump Performance and Installation 1. The factory provided pump on PW heaters and the recommended field provided pump for model VW heaters are sized to provide proper circulation through the heater and heater-to- tank circulation loop (see Figures 11 and 12).
Mighty Therm Volume Water Heater Page 11 Figure 11. Hot Water Supply System (Model VW & PW). With V ertical T ank With Horizontal T ank NOTES: Heavy line indicates Heater to Tank Circulating Loop.
LAARS HEATING SYSTEMS Page 12 CAUTION: 1. This piping arrangement is required on split systems to provide constant hot water temperatures. 2. Pipe size and length must conform to the recommendations for each heater model. 3. A loop circulator is required to maintain forced circulation in the building hot water piping system.
Mighty Therm Volume Water Heater Page 13 Figure 15. Single Installation Piping Diagram, Model IW. Figure 14. Dual Installation Piping Diagram, Model IW. NOTES: 1. All water connections 2" N.P.T. models. 2. Drain valve per ASME requirements. 3. A loop circulator is required to maintain forced circulation in the building hot water piping system.
LAARS HEATING SYSTEMS Page 14 Figure 16. Two-Temperature Hot Water Supply System (Model VW or PW). With V ertical T ank With Horizontal T ank Legend B - Check Valve in Hot Water Supply to Tempering Va.
Mighty Therm Volume Water Heater Page 15 Figure 17. Two-Temperature Hot Water Supply System with Vertical Tank for Models VW and PW Water Heaters. Legend B - Check Valve C - Check Valve D - Tempering .
LAARS HEATING SYSTEMS Page 16 2 I . Water Pressure It is very important that water pressure in the system be maintained above 30 psi. If the system pressure should drop below this, the vapor pressure of water in the suction side of the pump can cause hammer and cavitation in the pump and damage the heater through lack of water circulation.
Mighty Therm Volume Water Heater Page 17 proven to be lit. Whenever the pilot flame is interrupted, the main gas valve closes within 0.8 seconds. b. Electronically Supervised Standing Pilot System (System #16): When pilot flame fails, the ignition control module responds in less than 0.
LAARS HEATING SYSTEMS Page 18 gas supply, the automatic safety shutoff devices must be checked. 1. Before beginning the tests, make sure the main manual gas valve, and any other heater firing valves are in the “OFF” position. 2. Make sure the heater’s power switch is in the “ON” position.
Mighty Therm Volume Water Heater Page 19 depressed for one minute then release. Once the pilot is lit, the power is supplied through the aquastat to the main gas valve. 2. To set the temperature and high-limit controls: When using a tank aquastat: Set the tank aquastat to the desired tank temperature.
LAARS HEATING SYSTEMS Page 20 Lower the front of the burner (to avoid damaging pilot shield) then remove the burner tray. Caution Black carbon or green soot on a dirty heat exchanger can, under certain conditions, be ignited by a random spark or open flame.
Mighty Therm Volume Water Heater Page 21 II. HEATER IS POUNDING, KNOCKING OR EMITTING STEAM FROM RELIEF VALVES. Possible Cause What To Do A. Low or no water flow. A. This condition is usually caused by lack of adequate water flow through heater. Check the following: 1.
LAARS HEATING SYSTEMS Page 22 Key Description Model Model Model Model Model Model Model Model Model N o 50 0 6 00 71 5 8 50 1010 1200 1430 1670 1825 1 T op Panel Assembly 10535701 10535702 10535703 10.
Mighty Therm Volume Water Heater Page 23 Figure 22. Parts Identification. NOTE: T emperature Control Wells - Inlet/Outlet Header 1. Firing Mode L, K, & C - 2 Dry Wells 2. Firing Mode H A. Natural Gas Boilers & Heaters 500 thru 850 - 2 Dry Wells 1010 thru 1430 - 3 Dry Wells 1670 thru 1825 - 4 Dry Wells B.
LAARS HEATING SYSTEMS Page 24 Key Description Model Model Model Model Model Model Model Model Model N o 50 0 6 00 71 5 8 50 1010 1200 1430 1670 1825 2 1 T ile, Heat Shield/Spcr , Frt.
Mighty Therm Volume Water Heater Page 25 Figure 23. Tile Assemblies..
LAARS HEATING SYSTEMS Page 26 Key Description Model Model Model Model Model Model Model Model Model N o 50 0 6 00 71 5 8 50 1010 1200 1430 1670 1825 4 3 Ignition Control, Electronic E0100900 E0100900 .
Mighty Therm Volume Water Heater Page 27 Key Description Model Model Model Model Model Model Model Model Model N o 50 0 6 00 715 85 0 1010 1200 1430 1670 1825 6 4 Safety Gas V alve, On-Off, T wo St ag.
LAARS HEATING SYSTEMS Page 28 Key Description Model Model Model Model Model Model Model Model Model N o 50 0 6 00 71 5 8 50 1010 1200 1430 1670 1825 8 9 Plug, 3/4, Sq.
Mighty Therm Volume Water Heater Page 29 Figure 21. Outdoor Parts..
LAARS HEATING SYSTEMS Page 30 Key Description Model Model Model Model Model Model Model Model Model N o 50 0 6 00 71 5 8 50 1010 1200 1430 1670 1825 1 T op Panel Assembly 10660701 10660702 10660703 10.
Mighty Therm Volume Water Heater Page 31 Key Description Model Model Model Model Model Model Model Model Model N o 50 0 6 00 71 5 8 50 1010 1200 1430 1670 1825 7 Front Support, Flue Collector 10662101.
Pump Rotating Sections and Repair Parts Check pump assembly on heater for H.P . rating and find correct Laars part number from table below . Description 1/4 HP 1/3 HP 3/4 HP Pump Rotating Assembly, B&.
An important point after buying a device Laarsen Associates PW (or even before the purchase) is to read its user manual. We should do this for several simple reasons:
If you have not bought Laarsen Associates PW yet, this is a good time to familiarize yourself with the basic data on the product. First of all view first pages of the manual, you can find above. You should find there the most important technical data Laarsen Associates PW - thus you can check whether the hardware meets your expectations. When delving into next pages of the user manual, Laarsen Associates PW you will learn all the available features of the product, as well as information on its operation. The information that you get Laarsen Associates PW will certainly help you make a decision on the purchase.
If you already are a holder of Laarsen Associates PW, but have not read the manual yet, you should do it for the reasons described above. You will learn then if you properly used the available features, and whether you have not made any mistakes, which can shorten the lifetime Laarsen Associates PW.
However, one of the most important roles played by the user manual is to help in solving problems with Laarsen Associates PW. Almost always you will find there Troubleshooting, which are the most frequently occurring failures and malfunctions of the device Laarsen Associates PW along with tips on how to solve them. Even if you fail to solve the problem, the manual will show you a further procedure – contact to the customer service center or the nearest service center
