Oil Furnace in Spain

J Parker

I have a home in Spain and cannot get the heater to operate. I'm on a long waiting list trying to get someone to look at it and I'm going to dive in and see if I can't fix it myself.

The furnace is oil fired and heats the water for the house as well as the radiators. It provides the hot water just fine, but won't heat the water for the radiators. I've checked the thermostat and have even shorted across the 2 line voltage wires that connect to it. The unit has three gauges on the front, water temp for hot water, water temp for the heater and pressure for the heater, all are normal except the heater temp which is zero. I've bled the air out of the system, although the water does not appear to circulate in the radiators at this point. Do most water/heat systems have separate burners and nozzles for water/heat? I'm looking for the next step. I know the oil supply is good since the hot water section works fine. The furnace is a Spanish Domusa brand.

Dale

Very interesting

Well, if you can post an electrical schematic for this furnace we can answer many of your questions like how many burner(s) does this thing have and how the pump is powered ect. I hope someone who has seen on of these things, perhaps one of the UK group will comment. Does the hot water side work with the electricity turned off? Maybe a drip burner like an AGA. When you "jumped" the stat, any sparking. Everything I saw in Spain was 220 Volts so If a circuit was present should be some spark. If you can scan the schematic or wiring diagram, that will improve my guesses at least.

DaveGateway

There must be a circulator pump

See if you can hear or feel it running.

Weezbo

never seen one..though i will see if i can think it...

1).turn off the power. get a simple appliance cord connect it to the pump by taking out one screw detaching the two wires that you see and reconnecting them to the two lines you just disconnected on the pump., put wire nuts on the lines comming to the pump from the boiler control....2).get your test meter leads under the wire nuts From the boiler control. 3). turn the power back on to the boiler.go turn a thermostat up...did the meter gage read power? Yes? the pump is not getting a ssignal to Go. No? plug the power cord back into a receptacle if you hear a growl un plug it and plug it right back in wait one second if it still growls ...unplug it there is either lots of air in the lines or the pump is on its last leg. Should there be no growling noise let pump run a bit and check the temperature of the pipe beyond the zone valve or pump try this first.i am here for a while.

Weezbo

never seen one..though i will see if i can think it...

2). now systematically open any other zone valves you may have. 2).if you have determined the pump was bad replace it ,if you determined it was good buh no siginal reaching it let it run on the appliance cord...And Open all the valves (zone valves to the system) now you have to make some choices because the rest of this is can let smoke outta the devises if you arent careful....magic smoke IN Good,magic smoke Out Bad. also at thisjuncture if you have heat circulation it will increase to rather uncomfortable levels in all likelihood within the day.so,the next idea is to put a line voltage thermostat to the pump if it was all fine ,to have rudimentary control over the system. this would entail getting some # 14 stranded run it over to somewhere near a room you would like heat in or, ten twelve feet from anything that looks like its got anything to do with the boiler thiswill allow the thermostat to "control" the temps to a more comfortable level. this wire pair) goes back to the pump and is connected to one of thepump wires and one of the appliance cord wires. this has to be a line voltage thermostat,nothing fancy. now the boiler will run the pump will go thet stat will sorta control the comfort levels.....you may haveto observe the set it and forget it rule once you have thet stsat dialed down to a level near room temp of the boiler room at ten ->twelve feet.

Weezbo

so Then What?.....

well the next thing is i would check any control devises that operate in conjunction with the transformer controling the zone valves........ the transformer is some times protected by relays ...seldom if ever are these relays the problem ..thetransformer on the other hand well it needs to be tested with that meter you have see if there is a reading on thelow voltage side, if you have a voltage reading it would be useful information to anyone assisting you. the boiler,mayalso have a controler with low voltage leads that carry a signal from the thermostats to the boiler telling it to Go.USUALLY. you must be very careful as there are Line voltage zone valves and these likely have a relay that makes a signal to this wire......once we are away from this rudimentary electrical it can begin to get decidedly variant...so we need to either have a j p e g of the boiler and controls like a picture or two ,or a control wiring dia gram ,in a minit i am off to work... the pictures and a reply as to the out come so far of the "by pass wiring "would also be relavant to anyone who continues with you if it hasnt at least started working with the work you have done. I be back much later this evening my days go long in winter. everybody wants heat...Yesterday! *~/:) poco a poco uno se vas legos

Weezbo

The Spanish Domusa web site is blocked on my computer

due to some privacy protocol i have set and have little urge to change. you do the leg work and send us a couple photos.......