1. What is the difference between water filler valve and pressure regulator for a boiler? Is it just the factory preset or is there some difference?
2. Incoming pressure is 80psi. I have the water heater reduced but I can’t remember about the boiler. If the boiler is not reduced, do I need pressure regulator then a filler valve? Watts website has both types and both handles up to 100psi, so do I need pressure reducer? It seems filler valve would act as pressure reducer.
3. Watts also have combination of valve and a separate strainer. Is this strainer easy to clean? If I apply plumber’s grease to threads, would it protect the threads from corrosion and make it easier to clean later?
4. Watts used to have stainless strainer that could be removed from bottom like Bell&Gossett, but looking into it today I was surprised to see that the strainer is inside the valve body and the instruction says it should be cleaned twice a year. Strainer is also brass. I cleaned another valve years ago which was B&G and that had corroded and rotting strainer. I ended up replacing the whole valve. Since then I did not clean it because I am afraid of looking inside it. So just how important is the condition of the strainer?
Thank you in advance.
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You can have a fill valve for a boiler that is manual and you set your pressure by hand; a combination valve with a pressure regulator will automatically keep the pressure at a pre-set point.
If you have 80lbs. incomming pressure you need a PRV on your main water comming into the dwelling, 80lbs. is the maximum that you are allowed to use in a house; you never run your pressure that high, it can cause problems with your system, wear and tear, banging pipes and relief valves blowing off if there is a spike in the incomming preasure. Unless you have a PRV on your water heater you don't have it reduced, if you think that throttling down the valve on the water heater will reduce the pressure, it won't.
You boiler should have a automatic pressure fill valve with strainer and you have to clean according to the manufactors instructions. If you don't clean them you could destroy the valves ability to automatically adjust your pressure in the boiler. Depending on the type of valve you have it could be advantages to use water proof grease on the threads.
If you end up with putting in a main PRV valve keep in mind that you will have to add a expansion tank at or near your water heater, hope this helps.
Thank you for the reply. Water heater already has PRV. I got Watts pressure regulator valve for the boiler as well as back-flow preventer for that line. The PRV is preset at 12-15 psi. Do you mean that I need to reduce the incoming water pressure before the water gets to the PRV for the boiler? Or is the PRV enough? The specs on Watts PRV says it can handle up to 100 psi.
I have another question that deals with strainer. Is there a separate strainer body that can be flushed clean?
Again, thanks in advance.
Edited 9/14/2009 2:29 pm ET by k1c
It seems unusual to have a separate PRV for a water heater, if thats what you have, do you have a expansion tank on the water heater?, if not you should. By putting the PRV there you create a closed system that may cause the P+T valve to release when the water heats up. (Some codes require all water heaters to have an expansion tank).
There are strainers that have a blow down on them whch you can install before your auto feed; since I don't know what model feed valve you have I can't say if that will double your strainers, I don't think it would hurt if the strainer? in the auto feed is clean when you install it.
Most of the time if you have excessive water pressure comming into the house you put in a PRV to lower all the pressure, the boiler always has a separate PRV or manual control to keep it at its' recommended pressure.
80LB. incomming pressure can spike well above the maximum rating on your PRV'S depending on the time of the day. You probably have it reduced on your hot water but, the cold line gets the full pressure which can cause excessive wear and tear on you system. You may go years without any problems, your call to install or not install a main PRV. Luck.
"If all else fails, read the directions"
I have it on very good authority that the pipes will not blow up at 81 psi.In fact the whole system is happy at 115 and WH life seems to be good.And PlumberBill has made similar comments..
William the Geezer, the sequel to Billy the Kid - Shoe
I have it on very good authority that the pipes will not blow up at 81 psi.
In fact the whole system is happy at 115 and WH life seems to be good.
And PlumberBill has made similar comments..........
Bill: I didn't say anything about pipes blowing up at 81psi.
If you want to run your system at 115psi thats your choice, but good practice is to run it at the LEAST amount that will work with your system.
I don't know how PlumberBill relates to my original post?
Bill, you have me confused!
"If all else fails, read the directions"
You said that the pressure should be reduced from 80. And 80 is allowed by the code. So why the bother of reducing it..
William the Geezer, the sequel to Billy the Kid - Shoe
Bill: I thought I explained in my original post that water pressure will spike on a municipal system due to the time of the day, i.e. night. It then can excede what you have during the day; if you are close to the maximum it's easy to go over the 80psi recommended max.
Like I said, if you like the high pressure, go for it, but it's not good practice.
"If all else fails, read the directions"
Thank you for the reply. The house has been doing well without PRV for over 50 years, fixtures as well, for example, there are no water bangs in the faucets or toilet.
I am not a plumber and I used to research a bit then replace when one part went inoperative, such as PRV. Thank god that original plumber saw fit to place temperature and pressure gauges on both boilers and water heater (before and after PRV). Water heater does have expansion tank. I do most of repairs by example, just copying the layout and broken part. I do understand some about regular plumbing but not much about heating.
Watts sells PRV with separate strainer but it must be fairly recent addition because the plumbers supply store was not aware of it. When they called the distributor to find the price, it turned out about 3 times the cost of PRV alone, including the shipping. I decided to replace the PRV only and replace it again in about 7-8 years. It turns out cheaper this way. 7-8 years is about old PRV lasted. Again, thank you for the advice.