How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Rick Your Own Question
Rick
Rick, HVAC Supervisor
Category: HVAC
Satisfied Customers: 19495
Experience:  40+ yrs. experience as a licensed oil & gas technician.
94766
Type Your HVAC Question Here...
Rick is online now
A new question is answered every 9 seconds

I have a Buderus hot water heater/storage tank model #SM300/1,

Customer Question

I have a Buderus hot water heater/storage tank model #SM300/1, I have no hot water. Is there a re-set button? The radiant heat still works but no hot water to the rest of the house. What could be wrong?
Submitted: 8 months ago.
Category: HVAC
Expert:  Rick replied 8 months ago.
Welcome to Just Answer, my name is ***** ***** I will do my best to help you with your issue. If my initial response doesn’t answer your question then let me know and we can continue our conversation.There is no reset button. If you have heat then the hot water from the boiler isn't circulating to the tank to heat the water in he tank. Do you have a zone valve or a dedicated pump controlling water flow to the tank?
Customer: replied 8 months ago.
from the tank it splits off one side goes up into the boiler the other side goes into the zone valves.
Expert:  Rick replied 8 months ago.
Ok what brand zone valve?
Customer: replied 8 months ago.
Grundfos
Expert:  Rick replied 8 months ago.
Ok, move the lever on the zone valve head (that controls the tank)to the left. Do you feel any resistance?
Customer: replied 8 months ago.
They turn ok
Expert:  Rick replied 8 months ago.
Not what I was looking for. There is a lever on the zone valve motor/operator. I need you to move that lever not a nearby ball valve. If what I'm saying doesn't fit what you're seeing I need a picture of the zone valve for the tank. Click on ADD FILES next to the SEND button
Customer: replied 8 months ago.
The photo locks up the screen preventing me from sending. Pipe is warm on feed side and cold on opposite side returning to tank
Customer: replied 8 months ago.
Two other zone valves are warm on both sides.
Expert:  Rick replied 8 months ago.
Well you either have a bad zone valve (assuming you have zone valves since Grundfos valves are very uncommon but their pumps are not). Or a bad aquastat or sensor on the tank. Let's look at the tank for now. Is the there an aquastat (most likely Honeywell) with a dial you can turn to adjust the temp?
Expert:  Rick replied 8 months ago.
This ia a Grundfos zone valvehttp://www.supplyhouse.com/Grundfos-97627419-3-4-Sweat-UP-ZV-2-Way-Normally-Closed-Zone-Valve-with-End-Switch
Expert:  Rick replied 8 months ago.
This is a Grundfos zone valvehttp://www.supplyhouse.com/Grundfos-97627419-3-4-Sweat-UP-ZV-2-Way-Normally-Closed-Zone-Valve-with-End-Switch
Customer: replied 8 months ago.
It's a pump. There is no thermostat or dial but two probes sticking out on the back
Expert:  Rick replied 8 months ago.
Ok, then you probably have a bad sensor. Since you have a sensor I have to assume you have a Buderus boiler. Since it's far less likely the boiler control is faulty a bad sensor is the most likely culprit. But it would be worthwhile to check the connections from the sensor to the boiler terminal strip.
Expert:  Rick replied 8 months ago.
It's also possible you have a bad pump. If you have a multi-meter test to see if you have 120 vac at the pump for the tank.
Customer: replied 8 months ago.
I don't have a multi meter here at home, the terminal connection is secure.
Expert:  Rick replied 8 months ago.
The only way to diagnose this is with a meter. There's a very slim chance there's air in the boiler loop but this almost never happens with an indirect fired tank particularly if you have heat
Customer: replied 8 months ago.
Well I guess this get resolved today then.
Expert:  Rick replied 8 months ago.
I think you meant you can't resolve this today. That may be the case. I'd appreciate a favorable rating. I've given you the info you need to diagnose this. If you have more related questions I'll respond even after you've rated me favorably.

Related HVAC Questions