How to Install a Residential Hot Water Boiler

Boilers heat incoming cold water and pump it around the building.

Hot water boilers are an important part of your home, allowing you to have hot running water for baths, showers and dishwashers. The cold water feed is attached to the boiler and heated, Then another pipe carries this heated water around the property. Installing a hot water boiler can be a tricky and time-consuming business, so if you are unfamiliar with plumbing, it may be wise to hire a professional.

Things You'll Need

• Water heater
• White sealing tape
• Pressure relief valve
• Pipe wrench
• 2 plastic-lined steel nipples
• 2 copper pipe fittings
• Emery cloth
• Soldering paste
• Roll of solder
• Propane torch
• Rag
• Soapy Water
• Metal vent
• Screwdriver
• No. 6 sheet metal screws
• Yellow sealing tape
• 4-inch gas nipple
• Flexible gas supply hose

Instructions

1. Put the water boiler in position against a wall, using blocks to support it if required. Wrap the male thread on a pressure relief valve in white sealing tape and screw it by hand into the relief valve inlet (normally found near the bottom of the heater). Tighten the valve in place using a pipe wrench.

2. Take two plastic-lined steel nipples and wrap tape twice around both ends. Screw these into the water supply inlet on the heater and the outlet on top of the heater, tightening them with the wrench. Screw one of the copper pipe fittings onto the other end of both plastic nipples.

3. Solder the copper water supply pipes to the fittings. First, use your emery cloth to sand the ends of the copper pipes, as well as the inside of the fittings. Push the pipes into the fittings after first applying soldering paste to each of the ends. Unravel 10 inches of solder and use a propane torch to seal where the pipe enters the fitting. Use a rag to wipe away any drips.

4. Take a metal vent through the outside wall and place the end of it over the heater's draft hood on top of the hot water boiler between the two nipples. Fix in place with six screws into the predrilled holes in the top of the boiler.

5. Take a black-coated 4-inch gas pipe nipple and wrap yellow sealing tape around both ends. Screw this by hand into the gas control valve on the underside of the heater, and tighten using the wrench. Wrap yellow tape around the thread on the gas shutoff valve, and then screw the end nuts on a gas supply hose to both the gas shutoff valve thread and the end thread of the gas control valve. Use a wrench to tighten these into place.

6. Switch on the gas shutoff valve and apply soapy water to the gas hose nuts. If the water bubbles, tighten the nuts until the gas has stopped escaping.

7. Close the drain valve and switch on the water shutoff valves on each of the incoming and outgoing supply pipes. Light the pilot light of the boiler and turn the dial to your desired temperature. Wait for half an hour and check whether running water is available by turning on a faucet.

References

• The Family Handyman: Replacing a Water Heater