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ryan04 09-23-2010 07:52 PM

Prestige Boiler keeps blowing a fuse, no heat for days!!
Hey guys, I've got a triangle tube prestige honeywell boiler that's about a year and a half old. The power went the other day, and when it turned back on we had no hot water or heat. I checked the internal fuse on the mother board and the 5 amp fuse was blown. I replaced it and turned the power back on, and immediately it popped again. I phoned the plumber who put it in and he said it's not under warranty and that the mother board is probably fried. SO he got me the mother board at cost....$605 plus tax. I picked it up today and installed it in the boiler. I turned on the power and pop! same thing. So I then checked the transformer ohm's. I don't know which line was what because it's all sealed, I got 1ohm on one side and 4 on the other. What do you guys suggest? Does anybody know the ohm values that should be there? OR what else I should be checking??! I need help cause I'm getting sick of boiling water for bath's and I keep getting bounced around between companies with nobody actually doing anything! At this point if I can diagnose the problem at least I can get parts at cost, which I shouldn't even have to.

OH yea the transformer info was written: TYD E1 78/40.5 primary 125 50/60htz secondary 25 77.5VA

Artco 09-23-2010 09:09 PM

Did you call the factory to check for warranty? You can also explain to them the problem you are having.
How familiar are you with this system? Is it natural gas?
If it is shut off the manual gas valve when you are checking or changing this board.
Can you unplug all the plugs going into the board and install a new fuse. If the new fuse does not blow then plug in one plug at a time until one blows the fuse. Then look on the wiring diagram and follow the wires coming off that plug to see what they are connected to. Then one at a time see what that plug feeds and go from there.
Are there two fuses on the board?
I think you should call the company (manufactuer) and find out who they recommend for service in your area especially if you are not familiar with electric circuits.

kenmac 09-23-2010 09:36 PM

check your wiring . You have a short somewhere. That fuse is there to protect the board / transformer

ryan04 09-23-2010 10:33 PM

Prestige Boiler fuse update
OK, so I took some of your advice and unplugged everything on the mother board and replaced the fuse. I then plugged one connector in at a time to see what causes the fuse to blow. I got to the 125V connector and that blew the fuse. SO I bent myself into a very uncomfortable position and read the transformer specs off the transformer. I'm getting 125V from that connector going into the transformer, and instead of 24V coming out I'm getting 63V! From there the circuit goes to the DC side of the circuit through that 5A fuse. SO bad transformer.

ryan04 09-23-2010 10:39 PM

I plugged each connector in one by one until the fuse blew. It's the 120V connector to the blower, circulator and Ignitor. I think it goes from that connector to the transformer to give 24V then through that fuse and then into the board. I tested the transformer and I got 125V in and 63V out. It should be 24V out. SO I think it's safe to assume the transformer is blown.

beenthere 09-24-2010 04:59 AM

Keep your post about this boiler problem in 1 thread. It makes it easier for people to follow and understand.

kenmac 09-24-2010 07:01 AM

if transformer were blown.. You get 0 v out

Artco 09-24-2010 07:40 AM

If the tramsformer is shorted internal then it is possible the 63 volts would show up.
I don't understand if the fuse blows how are you able to measure 63 volts off the transformer? Does it take awhile for the fuse to blow?
I assume the transformer has shorted internally. If not then either the igniter, circuilator or blower has a problem.
My bet is the transformer.

ryan04 09-24-2010 11:27 AM

The fuse is a fast blow 5A fuse, and I think, I don't know for sure, but I think the transformer is just before the fuse in the circuit? So even though the fuse is blown, I still get 125 on one side and 63 on the shorted side.

Artco 09-24-2010 12:54 PM

Turn the power switch off then install a new fuse, then un plug the low side (24volt)of the transformer from the board, Then turn on the power switch, does the fuse blow?
If the fuse did not blow then with out plugging in the 24volt to the mother board check the voltage from the low voltage side of the transformer.
If you are still getting 63 volts the transformer is NG.

Make sure you are getting 120 volts for your furnace feed.

There should be no reason to get the 63 volts you are getting unless your meter is wrong or the transformer is shorted.

ryan04 09-24-2010 06:13 PM

OK so I replaced the surge transformer and we're still blowing a fuse. So I'm on to the rest of the circuit. Blower, circulator, and ignitor. Took some measurements with the new transformer and they're the same as before. At least my frustration keeps me warm ;)

beenthere 09-24-2010 08:14 PM

Remove all low voltage wires from their terminals. Put them back on 1 at a time. When the fuse blows, you know which part of the circuit has a problem.

Artco 09-24-2010 08:48 PM

Did you disconnect the low volt side of the transformer and check voltage out?

ryan04 09-25-2010 06:18 PM

OK we solved it! It was the circulator. I unplugged everything like you said, and started to plug in each connector one at a time with a good fuse. Once I got the AC side of the circuit it blew. So within that circuit is the mother board, surge transformer, igniter, circulator and blower. I replaced the mother board, did nothing, took it back. Replaced the transformer, did nothing, took it back. That's 2 for 5, I then unplugged the blower, did nothing, so I plugged it in again. That's 3/5, so I moved on to the circulator. I unplugged it from the circuit and the boiler booted up finally with an error code. I then pushed the reset on the unit and it booted it up properly WITHOUT the circulator and began to run like normal. There are 3 pumps in total, and with this system apparantly, if the internal circulator pump goes the other 2 pumps take its place and can limp you along. The other two pumps are one for the boiler tank and one for the hotwater in our floor. So as of now, all is good, warm floors again, hot shower, happy wife. On monday the plumber is coming over to replace the circulator under warranty. Thanks guys.

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