Radiator Help

IB34

Hello everyone, I have 3 radiators that won’t heat up. I have tried several different new air vent valves on them (Gorton,Varivalve, Ventrite). I have even replaced the main air vent valves. 2 radiators won’t heat up which are on the first floor. The other one is upstairs and only heats up if I leave the air valve off. No steam comes out of it once it’s hot so for now I have left it like that in order to have heat in that room. This particular radiator is really long compared to the others. I don’t know what else to try. Thanks everyone 

Steamhead

@IB34 , where are you located?

Big Ed_4

Oil or gas ? Is this a new problem ?

JUGHNE

All of the above plus....

What pressure does this run at?
Does the boiler shut down too early because of tstat?

IB34

I am located in downstate New York.
The boiler runs off of LP gas. 

This is my first winter in this house. These problem radiators used to heat up at one point but lately they don’t even get warm. I do not think the boiler shuts down too early. All the working radiators are nice and hot by the time it does turn off. The only pressure gauge I see has stayed at 0. Have currently had the boiler running for about 10 minutes 
I will attach some pictures of my boilers 

IB34

Steamhead

That boiler was made by Dunkirk, and as usual it was not installed properly. They provide piping instructions for these boilers. They really do. But I suppose reading and following them is too much work.

However, that's not causing your problem.

Does the boiler have an automatic water feeder? Has it been feeding a lot lately?

IB34

Im not sure how to tell if it has been feeding a lot however here is the automatic water feeder 

EdTheHeaterMan

OK it has fed 23 gallons (measured by electric timing not actual gallons, but it's close) since it was last reset or since it was installed. You want to keep a record of that and the date. See how much it changes over the next week, month... and record it periodically. This will tell you if you have a leak in a return pipe or somewhere else.

Your pressure control appears to be set to shut off at less then 2 PSI and come back on at about .75 PSI, which is fine, but that control is the low cost model that comes with the boiler and may not be that accurate. By the sound of your description, it appears that your system is not building up very much pressure. You need to find out if the burner operates for a longer cycle, will the problem radiators eventually get hot. Do this by setting the thermostat about 4° colder than you are used to. Then when the wife and kids complain about the temperature, adjust the thermostat to about 4° above your normal setting. This should give you a good long steaming cycle.

During that cycle you want to observe 2 things
1. If the problem radiators get warm or hot (or not at all).
2. If the burner goes off by way of the Pressure Control (or the LWCO). This will be obvious if your burner run cycle time stays the same, as if you are not doing this test. After some time the burner will restart and begin steaming again.

If the pressure control shuts down the burner and the room temperature is still below the thermostat set point, then you might need to raise the pressure .5 PSI.

If the burner does not go off until the thermostat is satisfied, then we need to reconvene, reevaluate, and regroup with this new information in hand.

Mr. Ed



PS
If I were your Pro, doing this on a service visit, it would cost you a small fortune in labor. But that's what I used to get paid for.

Hap_Hazzard

This is why I keep mine set at zero. I want to know if it's fed any water when i wasn't looking.

IB34

Thank you Mr.Ed. I will try that out this weekend and see what happens. I appreciate your help. 

JUGHNE

IB34, you have a CycleGard LWCO on your boiler.
It looks to be a 2090, meaning that every 20 minutes the burner shuts down for 90 seconds to let any foaming settle and then check the water level.

It may do this 20 minute cycle even if not firing. So you may catch it coming on early in the firing cycle.

Some replace them with a Hydrogard that does not do the cycle testing.
They can mess up your firing in various ways.

Just so you know that this can shut the fire down as you observe operation.

Hap_Hazzard

JUGHNE said:

Some replace them with a Hydrogard that does not do the cycle testing.

Did you men Safgard, or is this some new product I haven't heard about?

JUGHNE

Yes, I mean SafeGard 450.

Connects the same to VXT if you have one.