Dunkirk XE4 boiler stopped working

[craigibc]

Our boiler stopped working the other day and I was troubleshooting the system and when we bypassed the pressure switch it fired up. So I went to the local heating supplier store and they contacted Dunkirk and the pressure switch is no longer available for this model. They told the supplier to get a pressure switch that is .08 so he found this item attached.

Went home and plugged the new pressure switch in and now the boiler will not fire and the bypass we tried before did not work either. Calling a heating guy in but wanted to know if you guys had any ideas?

Craig

 

[fitter30]

The only way to jump out a pressure switch it can't be jumped till venter fan comes on or it will fault out. Look at old switch where u can see the diaphragm next to the switch. Switch has a piece that sticks down not touching the diapham if u have a ohm meter or continuity tester it should read open check ur new switch. Boiler was made the 34 week of 91. When was the venter assembly burners and top to get cleaned? Boiler or vent isn't clean the switch won't make. 30 year old boiler part prices can be outrageous most are obsolete as u found. If thinking about a new boiler the condensing boilers that are 95% efficient are only that efficient when return water is less than 130° 86% above that temperature. Cast section like u have is almost just as efficient above 130° return but will last longer. As for as size did this boiler cycle in the coldest temps? Might want to pick a little smaller boiler. Boilers are more efficient when running longer.
Check with gas company for rebates.

 

[htmdude57]

the pressure switch is supposed to be .08 inches wc? the one in your photo says .80wc? not the same. they sold you the wrong one?

 

[Jim greengo]

Take the old 1 and thump it on the floor,try hooking it back up and see if it works.
Then take the 1 they sold you back and get the right switch.