more boiler help

dpframing

I posted last week about my Burnham boiler having a small leak from the pressure relief valve. Cold pressure is at 20 lbs. and 40 lbs. hot causing the valve to trickle. A couple replies thought it was the expansion tank ( as I did). Turns out the tank bladder pressure is 14 lb. and it sounds empty. I called the pros near me who sent out a guy last week who told me there was too much water in the system. He drained it slightly, the pressure dropped, and the leak stopped. $120 later, the next day the leak returns. Now they tell me they think it's a bad water feed valve. They want to charge me an additional $230, and the supervisor swears that if it doesn't correct the problem, he'll give me my money back.

My question is: can I try adjusting down the pressure on the Taco valve with the adjusting screw myself? When I bleed the system at the boiler at the beginning of the season to remove air, I can't get the pressure to flow under 18- 19 lbs. That's why I think the pressure on the auto fill valve is set too high. If I try loosening the lock nut, and turning the adjusting screw 1/4 turn counter- clockwise,  approximately how much will the pressure be reduced on the valve at that point? I'd like to try to tweak it slightly before the service guys come back for the additional $230. Maybe I can solve it. Any advice?      

ColoradoDave

Yes

Yes, you can try adjusting the valve yourself, however, I'd recommend going to Taco's website and downloading the spec sheet on the valve, so you'll know exactly how to adjust it properly.

I'd also consider asking for your money back anyway.  If a technician came out and said "You have too much water in the system" and ONLY drained some water off the system and wrote the bill... then he should have any and all certifications removed from his wallet and he should go work at Wal-Mart or a convenience store.

The FIRST thing he should have asked himself is.... where did the "extra" water come from.  Obviously, either A> the fill valve let too much water in... or B> someone hit the fast fill on the fill valve and PUT too much water in (related to A) or C> the water molecules themselves began reproducing on their own.

I'm betting it was A or B.... and for an hourly billable rate, he should have drained the boiler off and spent the next 20 or 30 minutes inspecting the rest of your system to see if the fill valve brought the pressure back up.

The final possible reason for your "high" pressure, is the height of the system.. "Rule of thumb: 2ft of height = 1 p.s.i.".... so if your boiler is in the basement of a 4 story house at roughly 9 feet per story... then the highest loop is 27 feet up generating approximately 13.5 psi just by the weight of the water.  However, I would presume that you'd have been having this problem since the day it was installed if the height of the system was the cause.

STEVEusaPA

i agree with Dave, but would add

You stated "Turns out the tank bladder pressure is 14 lb. and it sounds empty."  First of all, the expansion tank needs to be removed from the system to check it's pressure.  As far as "sounds empty", that tells you nothing.  The guy who came out just went with the obvious, instead of spending a little more time to actually diagnose the problem.

billtwocase

I agree

I like easy money too, but I prefer to do work that I can stand behind for an honest hourly rate. It sounds like more of an expansion problem when the water is heated. The tank should have been checked hands down. If the feed is in question, lower the pressure on the boiler, and leave the valve shut off for a couple of days or so. If the pressure stays close to where you left it, I would replace the valve. Sometimes it's not an adjustment, and could be more of a bad diaphram,

Tim P._3

other possibilities..

It could also be a perforation of the tankless/indirect coil, if your boiler is so equipped.

icesailor

Rising Pressures:

There's another reason I see all the time.

The fill valve is shot. I don't use Taco PRV's but Watts 1156F's. It used to be that the only ones that the suppliers carried were the cheap Cast Iron ones. The brass strainers would plug up and not fill. Pressure would drop and steaming might occur. Or air in the top of the system. Then, if you futzed with the fill part, the seat and diaphragm had scuzz on it and although the valve shut off when it should, it leaked by slowly and continuously. Causing the Pressure relief Valve to leak all over the floor.

I personally saw more than one boiler crack from lack of water. Not on me though.

I also found that the cast iron Watts 1156F valves are no longer available though they are listed. The brass ones are now priced as the Cast Iron ones were. It couldn't be from fear of liability for failing PRV's and cracking boilers. I'm sure of that. Quite sure. But not so sure.

I agree that a tech missed the call. I would fill the boiler to 12# or whatever and shut off the fill valve. If the pressure doesn't go up in time, it's a bad valve. If an indirect or a tank-less coil in the boiler, and the pressure goes up, its a bad coil that is leaking high pressure to low.

Any time I have ever tried to adjust an old fill valve, it leaked bye. And there have been discussions here that say that the fill valve belongs off. Insurance companies and some manufacturers demand that. Shut off the fill valve and see what happens. Just monitor the pressure and add water as needed. Like you are supposed to do aanyway.

Paul48

Minimum

Follow Taco's instructions to calculate the minimum pressure needed to keep the system full to the highest point of radiation.Twenty psi is way too high cold, and you're killing the expansion capabilities of the expansion tank.As stated, the tank must be removed from the system,and set to the same pressure as the auto-fill.Be careful, that little tank is surprisingly heavy. I don't believe your problem ,based on what you have said, involves a leaky tankless coil.You're basically doing what the clown that came out should have done.

billtwocase

Ice

If you want to use good feed/relief/backflow preventers, ect, try Conbraco. I dropped Watts years ago. They were garbage, and may still be. Either Apollo bought Conbraco, or vice-versa. Both great products

Long Beach Ed

Wise Words

Ice is speaking sooth when he cautions that if you mess with that ancient fill valve all you'll get is a leak.  Try turning off the valve that feeds it and see what happens. 



My bet is that the tank is shot.

Plumdog_2

math trouble

4x9=36 Dave.

icesailor

Watts 1156F PRV's

Bill2K's,

Those third world Watts 1156F's of old were the Cast Iron ones. You can only get the Bronze ones now. Top shelf, made in China like all quality plumbing and heating products we buy today. At least that is what my wholesaler says and carries.

I'm limited to what I can buy. I only buy from one wholesaler. What I have to replace will be a Watts. There might be a Conbraco in a bin but it is well out of date. They carry Califfi but it becomes a replacement and re-pipe on a replacement of a Watts.  

icesailor

I agree:

I agree with everything you say. But I never remove a bladder tank to check the pressure. If you shut off the fill valve to the boiler and put a hose in a bucket and open the drain on the boiler, if very little water runs out and the pressure immediately drops to zero, its almost a sure thing that the tank is shot. When it goes to zero, I put a tire gauge on the Schrader Valve on the tank. Whatever it reads, is what pressure is on the tank. If there is no pressure, the tank is probably shot. If water comes out, it is shot. I can add air but I will be back in a day or so.

If they are full of water, I try to blow the water back into the system and get it out of the tank. If it doesn't go out (and it usually doesn't), the tank will drop instantly like a stone when it finally goes past the last thread. I try to tie a 5 gallon bucket under the tank to let it fall in to. They weigh a lot when full of water and can do some serious damage before the sudden stop.

icesailor

Help:

If the tank is an Extrol, over 15 years old, replace it. And replace the fill valve at the same time.

Jean-David Beyer

Math trouble?

Maybe not. If the boiler pressure gauge is near the top of the boiler and the boiler is in the bototm story, and the radiator on the top near the floor, there would be only 3 stories of pressure.