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Service manual for pyrox vaillant mag 250/7 tzw m natural gas

How to change diaphram

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Gene Haynes

  • 5391 Answers

SOURCE: Rheem 300170 HWS service manual

1) Rheem does not post service manuals.
Call Rheem and ask why, since the other big manufacturers, AO Smith and Bradford White do post service manuals.

2) You need new propane gas control valve, and matching combustion parts to fit existing tank.

3) Rheem does not recommend changing gas type, especially from natural gas to LPG.
LPG is higher pressure, and burns much hotter and requires cast iron burner, unlike the lighter-weight metal used for Natural gas burner.
The manifold tube and thermocouple must match the gas control valve, and gas-type and have correct thread for propane.
The combustion chamber and heat transfer surface can also be heavier metal for propane heaters.

If you need further help, I’m available over the phone at

Posted on Feb 08, 2013


Sean Piquet

  • 1867 Answers

SOURCE: I recently moved into an apartment with a Vaillant MAG 250/7 water heating system in it. Ive never used a system like this and for the life of me cant figure out how to turn the damn thing on.

Ask a neighbour or 2 in your building who no doubt have the same system installed in their apartment.

Posted on Jan 06, 2016


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