9 replies to this topic

[marimir]

I have moved into a house with an oil fired tankless boiler that is four years old. Recently I began losing hot water pressure throughout the house. The first plumber came and replced a valve that was indeed broken -- it fixed nothing. He suggested I add an electric hot water heater and bypass the coil. He never called me back with an estimate. Another plumber came out today and took out the restrictor that was almost totally clogged -- I think the first plumber missed its existence. Today's plumber said we had exceptionally hard water and that we needed a filter system. I have tons of hot water now at a wonderful pressure. Now, I have two questions. If the plumber took out the restrictor completely -- I think he did -- and I'm only relying on the valve to balance the water pressure, is that safe? And secondly, what kind of filtering system would you recommend? (BTW, my dishwasher not cleaning the top rack of the dishes was a boiler problem, not a dishwasher problem... who would have thought?)

[marimir]

The "restrictor" was in a hot water supply pipe located just outside the boiler to the house -- and I suspect it was to cut back the pressure -- the pressure is wonderful now. It was incredibly slow even before there was this really slow problem for the last month. There is also a valve that he said I could adjust if the hot water runs out too quickly -- right now, it's fully open. Do I need both a valve and a restrictor? Apparently the restrictor was so clogged and corroded that it disintegrated. Should I insist on having another installed? Or can I just kick back the valve a bit and get the same results? The pressure isn't ridiculously high -- it's actually quite nice. The water is in my estimation perfectly hot and I like the new pressure. I just need to know that it is safe -- that my boiler isn't going to blow up or something.

The valve that had to be replaced was also totally corroded the screw that held it was simply broken off -- the plumber suggested that I take the valve to the city water office and ask what they were doing to soften the water. As I said, the boiler is only four years old, and the valve and restictor are corroded and totally eaten away. When we first moved here, the water company gave us stuff to put in the tanks of the toilets to take the iron out of the water -- the tanks were turning dark brown. We don't have to do that any more -- the water company did something fairly recently to improve water quality -- so maybe it was thr previous water situation that created the problems with the boiler to begin with.

Is it difficult to install the filter system you're suggesting? The cheap one?

Thanks ever so much for you interest and response. :)

[donn]

I think the "restrictor" referred to- is the tempering valve? it blends cold w/hot  and would restrict pressure   without it the water going to faucets would at boiler temperature. 

[marimir]

So the water in the faucets  isn't usually at boiler temperature? (it was always way hot here, just not a lot of it at a any kind of serious pressure.) What happens without one if I'm happy with the way the water temp and pressure is? Am I doing damgae to anything?

Actually now that I think about it, there is a mixer valve (maybe northeastern for tempering valve? :)) -- the first plumber talked about replacing it to see if it was the problem, but he couldn't find one -- said the company didn't make them any more.

[donn]

no,  water to faucets 140  degrees  max  -- boiler water 180-195 degrees  depending on climate of region  but, if your happy with  temps and pressure fine, no damage will be done to the system. but i'm really not sure what's being called a "restrictor" --yes mixing valve & "tempering" valve  are the same thing.  it is suppose blend cold with hot and keep an evenflow temperature  &  yes--they're still available last one i got was from home-cheapo   :)

[marimir]

In the first plumber's defense -- not that he deserves one   -- he said that the company that made that particular mixer valve no longer made it.  And I'm not sure what a restrictor is either -- it seems redundant to have a "restrictor" that slows down the water going to the boiler coil as well as a valve that slows it down. It's no wonder I had no hot water pressure as it seems it was being slowed down twice before hitting the coil.

[Rrey199]

The restrictor is to restrict the flow of water through the domestic hot water coil. Most residential DHW coils will heat a maximum of 3 gal/min. If your water system delivers more, you may run the risk of the water passing through before it can be heated properly.

This will be especially true when the boiler sits idle at it's low limit setting (140-160 degrees).

The flow restrictor is a common addition these days with the lower mass of today's boilers.

A water softener is a must for you, because it's only a matter of time until the coil itself becomes restricted with deposits. When that happens, you'll need a new coil or an acid cleaning.

Hope this helps

[Groovy Mike]

I hav ethe same type of boiler and I too installed a water softener.  This reduces the build up enough so that the coil only needs cleaning every 4 or 5 years.  The good news is that you can clean the outside easily enough yourself.  The bad news is that my service shop tells me that in NY you can no longer do the acid bath to clean the inside because of environmental regs.