Tankless coil (oil fired boiler) no hot water to shower valve

Bill Julian

I just installed a Symmons s96-2 I found that I'm getting little to no hot water through the valve.
Seems the cold is over coming the hot. There is HW everywhere else. Replaced the temp valve anyway. Coils seems good must be the SV.

Could it be that I need to use a Tankless spindle that Symmons makes? Weird though. She had a 3 valve diverter before I put in the Symmons Valve but said she never used the cold only the hot side of the 3-valve diverter.

Also what of a flow restrictor in the cold side of the valve? I just think its getting too much cold and not enough hot. When the boiler is on you get HW for a minute. When you shut the valve it will spike hot for 30 seconds then cold again.

Any thoughts beyond mine?

Intplm.

Hi @Bill Julian
The Symmons shower valve, if new is probably not your problem. This shower valve is one of the best and is easily repaired when needed.
The little to no hot water through the valve. Is that a temperature issue or a volume of water issue?
Is this happening at other areas, faucets, etc?

Please post some pictures. This would help in getting to the bottom of your issue.

Bill Julian

Its a temp issue. There is HW everywhere else. Im wondering if the tankless coil is going bad. Also the water pressure coming into the house is low. Outside faucet might spray 4 feet max. She had the problem with the 3 valve diverter too. She said she never used the cold side only the hot side and still low temp, real low maybe 100.

EdTheHeaterMan

FYI: I just had a my bathroom redone, new Toilet, Lav and Shower. The hand held fixture of the new shower had very low flow, while everything else had great flow and pressure. After hours of checking the valves and faucets in my new plumbing system, I have come to find out that there was debris in a combination check valve/strainer inside the metal jacketed hose that connects the handle to the diverter valve.

Clean the dirt from the new plumbing startup out of the hose strainer, Viola! The handheld has great pressure and flow now.

So, to make a short story LOOONG Check for dirt in the new fixture.

dko

Is this limit screw adjusted correctly?


Also, when you say there is HW everywhere else. The bathroom faucet has no issue correct? Is it low gpm?
If your other fixtures are working and there is no debris in anything TA-10-3HL should be your fix.

Bill Julian

To answer both of you. There is no dirt in the shower valve I blew out the system before putting it into operation taking off the spindle etc. The S96-2 has no "filter" screen in it. To answer the other question, yes
HW everywhere but lower pressure (not real low) but low. Bath faucet same Temp as kitchen. No debris in anything to slow the flow. The in floor 1/2 "tee" is hot going over to the vanity, the branch of the tee going to the Symmons is warm at best and gets cooler with time (1 minute).
The cold side of the symmons has more gpm it appears to me and the hot side less volume and of course less temp.
I think if it were the tankless coil the customer would have issues everywhere. However when introducing a pressure balance and temp control shower valve things change. The symmons demands pressure on both sides to operate and the pressure for the hot side is clearly less than the cold. Im talking pressure here only.

All the other faucets are not effected because they do not require the need to be balanced.

I pick up my TA-10-HL tomorrow. Thanks!

Bill Julian

O yes the limit screw is maxed out. The triangle symmons valve handle is pointing at 11 o'clock (maxed).

Jamie Hall

I'm thinking that the tankless coil may be badly scaled, reducing the pressure enough on flow so that the new valve can't compensate. You can try flushing it out and cleaning it...

Bill934

I’m going to replace the Symmons spindle first

If that doesn’t work, I might replace the coil

Bill Julian

Update: The TA 10 H3L fixed it. I tweaked the tempering valve slightly and the burner control. 185-165

Intplm.

dko said:

Is this limit screw adjusted correctly?


Also, when you say there is HW everywhere else. The bathroom faucet has no issue correct? Is it low gpm?
If your other fixtures are working and there is no debris in anything TA-10-3HL should be your fix.

Bill Julian said:

O yes the limit screw is maxed out. The triangle symmons valve handle is pointing at 11 o'clock (maxed).

Maxed out? That screw T-34 needs to be at least flush with the outer edge of the T-12A.
In your situation, I would try to bring it out even further. As far as you can without it leaking.
The handle position is not a factor.

And sometimes the T-10 has to be replaced along with the TA-4 seats. Try that.

Also. Be very sure that you have not double-gasketted anything.

Bill Julian

Im all set Water good now thanks!