Intermittent lockout problem with 20 yr old W-M Gas Boiler GV4, Series 2

Barbarrosa1

I have a 20 yr. old Weil-McLain GV4 Series 2 natural gas boiler with the UTC 1013-100 control module & White-Rodgers 36C98 gas valve. Also have a Weil-McLain water heat exchanger & Wirsbo floor heating with 3 zones. . I am having problems with intermittent lockout. Turn off power & boiler fires normally again. May go several days to a month then lockout again. Have followed W-M's trouble shooting guide & checked differential pressure at air pressure switch using a Dwyer Mark II #25 manometer. The reading was 2.1" W.C. at start of purge then dropped to about 1.7" W.C. during normal operation. Have about 30' of vent/intake piping. Original was PVC & was replaced on recall about 2 or 3 yrs. ago. Have checked all wiring connections, have 24VAC at air pressure switch, 129 VAC at main line connection at control module. Blower motor is rated 1.0 A pulls 3.1 A startup then drops to 0.99-1.02 during run. Replaced the igniter in October because of intermittent lockout but did not solve problem. Checked with magnifier all solder joints on back of control board. Could not see any cracks or problems. Also ck'ed Grundfos circulation pump, rated 0.74 A pulling 0.7+-. Suggestions??
Forgot to mention when the boiler locks out the green power light is on steady, the gas valve light is blinking red. Purge & ignitor lights are not on.

icesailor

Is that UTC-1013-100 control the original board or was it replaced with the improved board?

Many of the Series 1 & 2 boilers came with a controller that had issues and was replaced with a controller that says "Weil-McLain" all over it.

Barbarrosa1

The United Technology 1013-100 Board is original to this boiler. I thought of one other possible problem. The original venting was the PlexVent PVC that was replaced on a recall 4 or 5 years ago. Our house has original 3 layer stucco as siding that was applied after the W-M Vent/Air Intake Termination was installed. Our plumber/HVAC installer had retired so another HVAC company replaced the PVC venting under the recall. They used the original W-M Vent/Air Intake Termination. With this termination there is no elbow down or tee & this is installed on the West side of our house. Prevailing winds are normally from the West so I plan to add a Tee to the end to decrease pressure during high winds. I think I will buy & install a new UT 1013-200 control module.

icesailor

I'm not sure, but I don't think you can buy a UT 1013-200 control module unless it is used.

I had a customer with your same boiler. It was always going out, but the owner had someone else she called whenever the boiler acted up. There was a problem with the mixer which the gas guy fixed. But the boiler still went off regularly. He had replaced the UT-1013 with a used control he knew was OK. It still went off. The gas guy was unavailable. No heat or hot water. I went out and picked up the Weil-McLain replacement module for that boiler. It comes with a new wiring harness. It never went off again.

The control swap is an easy change out. changing the venting isn't.

Barbarrosa1

The Weil-McLain P/N 382-200-448 Integrated Boiler Control Unit (includes UT Module 1013-200) is available from SupplyHouse.com (formerly PEX Supply.com). This is the P/N listed in the Weil-McLain Service Parts Catalog/February 2007 for the Gold Module Conversion Kit. Reviews on their website are about 95% positive on use of this kit on several models of W-M boilers.

Barbarrosa1

I meant reviews on the SupplyHouse.com website not W-M. I downloaded & printed out the GV Series 1 & 2 Service Parts Catalog/February 2007 Discontinued Service Parts from the Weil-McLain website.

tim smith

There is a good possibility that you have restrictions in the heat exchanger of a 20 yr old GV boiler. We have dismantled several in that vintage to clean out all the deposits. Time consuming job. It could also be the module is weak, we do replace those with the gold conversion module from time to time. We have them on our parts shelves. Good luck, Tim

icesailor

tim smith said:

There is a good possibility that you have restrictions in the heat exchanger of a 20 yr old GV boiler. We have dismantled several in that vintage to clean out all the deposits. Time consuming job. It could also be the module is weak, we do replace those with the gold conversion module from time to time. We have them on our parts shelves. Good luck, Tim

How many of the Series 1 and 2 did you find with the HX full of rust and crud had the thermostatic by-pass broken and the boiler was condensing and rusting away?

If the GV is horizontally direct vented and the termination is outside and close to the boiler, look inside the vent from outside and see if you see rust chunks inside the termination. A good indication that the thermostatic mixer has gone toes up.

Barbarrosa1

This boiler does vent horizontally to the outside plus receives intake air from outside. Goes up about 12' then about 20' to the outside wall. Think I mentioned the original venting was PVC that was replaced under recall. So now is SS pipe. I have added a 6" pc of Al dryer vent rolled & pop riveted at the outside of the original W-M termination plate as had problems last Winter with frost & ice forming over the intake air vent. The boiler has been firing for about 10 days w/out lock out after I removed & inspected the 1013-100 module. Possibly one of the connectors at the module was not making good contact? Have the 1013-200 kit & a new ignitor on hand just in case! Thanks!

Barbarrosa1

Plan to have the boiler & system completely gone over by a local HVAC company with boiler experience this Spring!