Triangle Tube Phase III PG-45 Boiler Dead

Alan (California Radiant) Forbes

I've gotten so used to a screen and some kind of diagnostic readout on a boiler when there's a problem, but there's no such thing on this one and it's not making heat or hot water. I'm hoping someone has some experience with them and can point me in the right direction.

Currently, I'm focusing on this relay being defective and there no diagram to show me which terminals are for the 24 volt coil and which are for the switching contacts. It looks like a double pole, double throw relay. The unused terminals are either normally open or normally closed.

The smaller relay behind it is straightforward: single pole, double throw.

EBEBRATT-Ed

I think this is it. two brown wires are the coil. Relay contacts are both hooked up NO. Looks like 2 blacks on 1 pole and 2 blues or a blue and a purple on the other pole. Knock the dust off and you can see the #s

90-340.pdf

hot_rod

from the side you can sometimes see the small wires from the coil going up to the terminals.
Do you have 24 V anywhere?

109A_5

Maybe this will help. As @hot_rod stated is there 24 VAC ? 24 VAC is a good place to start, divide and conquer. Dead is often easy, find where the power stops.

I would call terminal 6 the C or Common, Terminal 5, 24 VAC Hot, the transformer's R terminal. Terminal 14, 24 VAC Hot to the burner through all the switching and limits.

https://assets.ctfassets.net/sj902orc9wh4/1N1Cq8x4qXaVHluJ8XzxUI/b19b470ee148faad5739f74e63cc4818/2002-50-Delta-Performance-Trouble-Shooting-Guide-.pdf

109A_5

Maybe the manual reset is open terminals 7, 8 ?

The relay coil can often be found with an Ohmmeter if other methods fail. In this case R2's coil are the two Tan wires which are switched on the high side by the room thermostat through other limits and the Secondary Thermostat.