Webster Boiler Return Trap - Size 0023A

Mike Doyle

70-yr. old residence, three levels, in Denver, CO. Two-pipe steam system, cast iron radiators with hand valves only, gravity return. Original, natural gas-fired boiler began to leak, and was replaced with a Smith GB-250-400. Heating capacity relative to heating load is fine.

Supplier recommended to the contractor that a condensate receiver/pump unit be added to feed the boiler off of a MM level controller. Cold water make-up via a float mechanism in the receiver.

First heating season this year. System is fired up - feed pump whine telegraphs through the piping in the house; water hammer at the Webster trap, and what appears to be an F&T trap piped next to it. Both of these devices are original, and reportedly worked fine before the boiler replacement. Unhappy homeowner.

The Webster has a boiler water reference line on the face of it, set at about 59 in. A.F.F. Centerline of the original, and remaining, condensate return header is about 15 in. A.F.F. The new boiler has a water line at about 24 in. A.F.F. A dimension for the water line on the old boiler was not taken prior to demolition; however, both the owner and contractor are confident that the top of the boiler in their recollection, and therefore the water line, was definitely less than 59 in. A.F.F.

It appears that the pump set can be removed, and the gravity return re-instated. The receiver may be retained, in order to replicate some of the lost water volume of the original boiler on the condensate side of the system.

Questions: (Until my copy of The Lost Art... arrives!) 1.) Is there a reference somewhere for information on the proper application of the Webster trap, and 2.) How sensitive is the placement of the device to the proper operation of the system (i.e., to eliminate the water hammer), now that the boiler water reference line on the device will be about 35 in. above the new boiler water line. (Raising the boiler will not be an option, due to the flue configuration.)

Thanks in advance, Dan and friends.

Mike Doyle

Webster Boiler Return Trap - Size 0023A

70-yr. old residence, three levels, in Denver, CO. Two-pipe steam system, cast iron radiators with hand valves only, gravity return. Original, natural gas-fired boiler began to leak, and was replaced with a Smith GB-250-400. Heating capacity relative to heating load is fine.

Supplier recommended to the contractor that a condensate receiver/pump unit be added to feed the boiler off of a MM level controller. Cold water make-up via a float mechanism in the receiver.

First heating season this year. System is fired up - feed pump whine telegraphs through the piping in the house; water hammer at the Webster trap, and what appears to be an F&T trap piped next to it. Both of these devices are original, and reportedly worked fine before the boiler replacement. Unhappy homeowner.

The Webster has a boiler water reference line on the face of it, set at about 59 in. A.F.F. Centerline of the original, and remaining, condensate return header is about 15 in. A.F.F. The new boiler has a water line at about 24 in. A.F.F. A dimension for the water line on the old boiler was not taken prior to demolition; however, both the owner and contractor are confident that the top of the boiler in their recollection, and therefore the water line, was definitely less than 59 in. A.F.F.

It appears that the pump set can be removed, and the gravity return re-instated. The receiver may be retained, in order to replicate some of the lost water volume of the original boiler on the condensate side of the system.

Questions: (Until my copy of The Lost Art... arrives!) 1.) Is there a reference somewhere for information on the proper application of the Webster trap, and 2.) How sensitive is the placement of the device to the proper operation of the system (i.e., to eliminate the water hammer), now that the boiler water reference line on the device will be about 35 in. above the new boiler water line. (Raising the boiler will not be an option, due to the flue configuration.)

Thanks in advance, Dan and friends.

Fred Harwood

BRT

In many cases, restoring the original water line and gravity return fixes lots of problems created by return pumps, which destroys the original water seals separating steam and condensate. Also, modern gas and oil burners controlled by a Vaporstat do not need BRTs, simply because the pressure differential between the boiler and returning condensate will not be more than 1psi or about 28 inches of water stacking. In short, a BRT is nonessential with modern control.

[Deleted User]

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of "Lost Art" (thru a magnifying glass) shows a minimum of 4" between the bottom of the return trap & the boiler water line. Does not give a maximum.